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KEY CONCEPTS FOR BUILDING AND LIFE SAFETY IN COMMERCIAL SPACES An Exposition Through the Existing Building Codes

Undergraduate Thesis By Kinjal Shah (2807) School of Interior Design, CEPT University Guide : Ar. Canna Patel


Declaration This work contains no material which has been accepted for the award of any other Degree or Diploma in any University or other institutions and to the best of my knowledge does not contain any material previously published or written by another person except where due reference has been made in the text. I consent to this copy of thesis, when in the library of CEPT University, being available on loan and photocopying.

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Dedicated to Life, Experiences, and the learning that follows ...


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Abstract Safety of occupants’ lives is considered one of the most important criteria when designing a new space or making changes in an existing one. Whether the interior project is small-scale or large-scale, it involves an abundance of parameters whose decision may sometimes be very sensitive for protecting occupants’ lives. Carefully deciding all the parameters simultaneously is often difficult, if not impossible, perhaps because changes in one parameter may affect the decisions for other parameters. Alleviating this difficulty is one of the reasons why building codes have been developed. They serve as an aid to all proffessionals who are involved in the design or construction — architects, interior designers, engineers, planners, etc. However, due to this generality, the codes are often tedious to go through. Moreover, they are only supposed to specify which decisions are safe or unsafe. Making informed design decisions in everyday life requires an understanding of the concepts that led to such specifications, and how various decisions rely on each other. To that end, this thesis studies the interior design concepts critical to building and life safety. For in-depth exploration, the focus is restricted to studying how such concepts aid in hazardous situations that require immediate attention. The concepts are derived from Indian as well as international building codes; while their specifications differ, the underlying concepts typically remain the same. Observations and results obtained during the study are organized in two parts. Part I begins by motivating why this thesis is important and for whom it is relevant. This is followed by an investigation of the construction type and the occupancy type of a building, which have significant impact on life safety, as they facilitate the detailed understanding of other concepts and govern many decisions. Part II of the thesis narrows down on how and why various interior design aspects affect safety in a space. For example, it is shown that interior concepts related to building services (e.g., electrical, mechanical, and plumbing services), interior materials and finishes, and signage are also very important for life safety. While the thesis focuses on a conceptual understanding useful for taking safety precautions during the design phase, the case studies presented at the end complement the thesis by illustrating how safety-critical details can be observed in a built environment. Note that the case studies do not intend to evaluate the level of safety present in the spaces chosen. It is concluded that, while buiding codes do aid in decision-making, it is important to understand how various design concepts relate to life safety. Achieving life safety is not a one man show; it requires greater safety awareness in everyone involved, from the design professionals to the occupants themselves.


Contents viii ix

PART I

: 01 02 06 09

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Preface Acknowledgement

BUILDING BASICS Introduction Inspiration for This Thesis Proposal How to Read This Thesis

Chapter 1

13

Construction Types and Building Classification

Chapter 2

21

Occupancy Classification

PART II

:

LIFE SAFETY

Chapter 3

33

Building Services

34 56 77 83

Chapter 4

89 90 97

Chapter 5 Office Mall

Chapter 6 Appendix A Appendix B Appendix C Appendix D

105 106 116

123

Fire Protection and Life Safety Means of Egress Plumbing and Mechanical Systems Electrical Systems

Interior Environment Interior Materials and Finishes Signage Design

Case Studies Sambhav Infrastructure Pvt. Ltd., Ahmedabad Gulmohar Park Mall, Ahmedabadw

Conclusion

126 128 129 130

History of Building Codes Abbreviation and Units Available Code Resources Observation Checklists

133 136

Bibliography Glossary


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Preface “ For safety is not a gadget but a state of mind. ”

- Eleanor Everet

Life is a blend of colourful experiences, some more memorable than others. However, what has always excited me is the learning that follows from these experiences. Fortunately, for me, both my academic and personal journeys so far have been streams of fascinating learning experiences. During my journey as an interior design student, I got the opportunity of working on a variety of projects. In my pre-final and final years, I took a museum and an airport, respectively, as my projects. During that time, I understood that in any public space which caters to a large number of users, the functional aspect of the design is equally, or sometimes more important than the aesthetic aspect. Further, optimizing the functional aspect requires considering a lot of details simultaneously, due to which taking design decisions may sometimes be very tricky. I always wondered: Are there any formal means to aid this thinking process? Can it be done by illustrating the consequences of the design decisions taken? Motivated by this question, my initial exploration led me down the aisle of systems thinking — a framework that helps analyze the interdependencies of various decisions through certain tools. Unfortunately, those explorations could not culminate into the thesis. Some time later, a new idea popped up during a chat with Prof. Snehal Nagarsheth —“investigating building codes for interior designers”. While developing this idea further for this thesis, I realized that sometimes only the codes may not suffice; taking careful decisions may require an understanding of the intent behind the codes as well. This thought process informed the development of my thesis towards illustrating the basic concepts underlying building codes so that the consequences of various design decisions and their interdependencies can be better understood. During this time, my image of building codes has changed completely. While earlier I thought of building codes as requirements and restrictions, now I look at them as tools that guide the thinking process by outlining the choices that would bear adverse consequences.


Acknowledgement It would not have been possible to write this undergraduate thesis without the help and support of many people around me, only to some of whom it is possible to give particular mention here. Above all, I would like to thank my guide Ar. Canna Patel for providing me the complete freedom of exploring my interests in my way while keeping an eye on my work and progress at the same time. Due to her broad knowledge and constructive advice, I never felt directionless. I particularly enjoyed learning from her how to express myself more confidently and how to organize work at the finest detail. Her constant guidance and encouragement have been invaluable for me on both academic and personal level, for which I am extremely grateful. I would also like to express my gratitude to Prof. Snehal Nagarsheth for suggesting the underlying idea of this wonderful subject. It was very kind of her that even in her extremely busy schedule, she was prompt in giving me very insightful discussions, without which the development of this subject would not have been the same. In addition, I would like to extend my sincere thanks to my dean Krishnaben and all my professors, especially Prof. Kireet Patel, Prof. M. P. Ranjan, Rajan Rawal, and Jay Thakkar, whom I have had the opportunity to learn from. I would also like to thank Kamalika ma’am for seeing my thesis through till the end, and K. D. Sir and Chandraben for the best administrative support and answering my repeated calls with all the patience! I am also very thankful to Ar. Kiran Kapadia and Mr. Mihir Shah for providing me their valuable time and effort for my thesis case study. I thank Tejal Chudasama-Jani for providing me a useful review of the real-world scenario of the subject. My big appreciation and thanks to all my girls—Ritu, Kamana, Rucha, Daphne, Shivangi, Apeksha, and Ankita—for their wonderful ideas and concerns that shaped my thesis well, Yash for always helping me out in the “so called urgent” situations, Ravi for all the learnings with fun and sharing the tasty tiffins, Digant for being the best friend and never saying “NO”, Jaymin for his constant support and motivation, and Samhita—whom I personally adore— for always being responsive and bringing clarity in my views. I am most grateful to my family—my brother and my parents—for their constant love, support, and patience during my entire academic journey. Last but by no means least, I want to thank Nisarg for giving me his unparalleled support throughout, as always, for which my mere expression of thanks does not suffice.

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PART I : BUILDING BASICS


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Introduction

In Introduction, • Inspiration for This Thesis • Example Study of Building Mishaps • The Current Scenario in India • Review of NBC 2005

• Proposal • How to Read This Thesis • Structure of This Thesis


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Inspiration for This Thesis Inspiration for this thesis stemmed from the observation that mishaps endangering human lives such as building collapse or severe fires are piling up day-by-day. A survey[1] says that, every year 25,000 people die in India solely due to fire hazard. A brief survey of selected building mishaps is presented below, followed by a summary of the current scenario in India with regards to safety standards and awareness, further followed by a brief review of the National Building Code of India.

Example Study of Building Mishaps

Introduction

What does one see when buying a house or any other place? May be how fashionable it appears, or may be whether the walls are painted properly, etc. Some users might be more concerned about the details, and might check the material used in the furniture and elsewhere, or the type of faucets used in the bathroom. But what about the electrical wires which run behind the walls, or the size of the ventilation? What about the provision for fire-fighting systems? Is it checked if the building is lawfully designed and appropriate standards are followed? Do these questions really matter? Maybe, maybe not. How can one check if the building occupied is 100% safe? One cannot. The users usually rely on the architects and designers that such parameters are taken care of. And as designers, it should be our responsibility to fulfil the trust of the users. But the reality may differ from this idealistic view. Below, some real-life examples are reviewed. Electrical Hazard And Fire Hazard AMRI Hospital Kolkata 2011 95 People Died

The fire originated due to a short-circuit, but was spread because flammable materials were kept in the basement where they were not supposed to be. That is, basement was used as a godown, violating safety norms.[2] Further, the death toll was high (95) because the fire-fighting facilities were inadequate and because hospital staff could not locate the emergency exits and stairs easily. Another reason why they could not evacuate the building is that most doors and windows were locked. More critically, lack of awareness regarding fire safety was evident when a similar fire broke out for the second time within 3 years.

Fire Hazard VS Hospital Ahmedabad 2010 1 Person Died Property loss worth of 4 crore

The fire could not be controlled because no fire hydrant system was installed.[3] While NBC clearly suggests the use of smoke detectors, a suppressant system, fire extinguishers and a fire hydrant system at hospitals, the hospital only had fire extinguishers, and the hospital officials believed that fire hydrants are only required in high-rise buildings.

1. Nair, R. R. Fire and Explosion Hazards. Industrial Safety Review. January 2013. 2. Horror hospital: Fire dept asked AMRI to clear basement in July. Firstpost. 9 Dec 2011. Accessed 1 April 2014. <http://www.firstpost.com/ india/40-patients-trapped-in-fire-at-private-hospital-in-kolkata-151524.html>. 3. VS: All Gas. Ahmedabad Mirror. 12 April 2010. Accessed 1 April 2014. <http://www.ahmedabadmirror.com/printarticle.aspx?contentid=201004 12201004120318147846976eaf8>.


3 Building Collapse Mumbai 2013 61 People Died

In this case, an interior decorator removed a central wall and supporting beams.[4] An important details is that the decorator was unauthorized and made the removals without the required permits.

Building Collapse Mumbai 2007 29 People Died

In this case, the site owner himself carried out renovations and expansion of interiors (with a few structural changes), which lead to the collapse in which 29 people died.[5] It was reported that the owner was not a certified professional.

Fire Hazard Kumbakonam, Tamil Nadu 2004 94 Children Died

The fire officials reported that building laws violated as kitchen and its thatched roof were close to classrooms; lack of emergency exits made it a “death trap”.[6] Also, the teachers had inadequate knowledge of emergency situations and mishandled the situation. Another major reason was that the management brought students from two schools together to mislead the inspecting authorities about the student-teacher ratio. They were unaware of the risks associated with increased occupant load (number of users of the space). Finally, the school had inadequate exit facilities and no firefighting capabilities.

The Current Scenario in India Aren’t these examples scary? They lead us to the thought-provoking question that every decision one makes, be it the designers or the users, has impact on others’ lives. Sure, aesthetics and comfort are important factors, but so is safety. Slightest oversight may lead to dreadful incidences that involve property loss or even loss of human lives. Agreed that incidences like the abovementioned ones inevitably happen at some scale or the other, but are we taking sufficient precaution to be able to prevent them in most cases? What is the current scenario in India in this regard?

4. Cook, L., Yan, H., and Udas, S. Decorator responsible for building collapse, killing 61. CNN. 30 September 2013. Accessed 1 April 2014. <http:// edition.cnn.com/2013/09/29/world/asia/mumbai-building-collapse/>. 5. Jeweller held for Borivli building crash. Times of India. 24 July 2007. Accessed 1 April 2014. <http://timesofindia.indiatimes.com/city/mumbai/ Jeweller-held-for-Borivli-building-crash/articleshow/2228648.cms>. 6. Walsh, Vincent. Supreme Court on Children. Human Rights Law Network, New Delhi, 2011. p. 51.


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Mr. G.B. Menon, former Chairman of the Fire Fighting Sectional Committee (CED 22), Bureau of Indian Standards and former Fire Adviser to the Government of India has a strong opinion in this matter. He emphasized that care must be exercised by each member of the construction team, during all stages of construction, and in every type of space.[7] “Be it a commercial or residential building, the safety of people is prime, and to ensure it, all stakeholders in the construction sector should be taking equal responsibility. Builders, architects, interior designers, workmen, the users, everybody has a role to play. An integrated approach is required starting right from the design stage and carried through to the construction and occupancy stages, to make certain that fire and life safety requirements are provided and maintained throughout the life of the building.” He also aptly puts the difference between the scenarios in India and abroad:[7] “In countries such as the U.S., the building code assumes the status of a law that gives the requirements for the design and construction of building and structures. The safety factors include structural design, fire protection, means of escape, illumination, sanitation, interior finish and upkeep and maintenance. We do not have a fire-testing and evaluating centre that can give us an idea about a material’s potential fire hazard. (In India) Fire and life safety of buildings is seldom given the serious consideration they deserve until an inferno claims lives and destroys property. We are all waiting for a disaster to happen to talk about corrective measures.” The issue of building and occupant safety has become more important today because hundreds of high-rise and special buildings have been erected in each city. The risks of fire are far greater in high-rise buildings due to various factors such as more combustible material present in the building, the stack effect of smoke, etc. However, the precautions taken fail to match the levels of risk. A fire brigade official stated on the site of a fire incidence[8]: “In most of the buildings, the electricity cables are not maintained properly. Sometimes, the use of sub-standard material by locals also leads to such accidents.” Such incidents have highlighted shoddy construction and violations of the building code amid burgeoning demand for housing in many parts of India. The Indian Institute of Architects, Kochi centre points out an underlying fundamental issue:[7] “(There are) no appropriate guidelines in designs or rules applicable in modifying an old building.”

Introduction

The common take-away from the above discussion is that in India, professionals involved in the constructions of buildings are less aware of the safety standards and fail to take the corresponding precautions, leading to fatal incidences and loss of many lives. This observation founded the prime inspiration for this thesis, in which basic concepts underlying the codes and standards are illustrated which may help designers acquire a better, more fundamental understanding of the codes. Further, in some cases appropriate guidelines themselves are missing, passing the burden of ensuring safety to designers. To that end, the thesis also points out concepts on which less emphasis may be given in NBC[9], but are deemed important elsewhere[10,11].

7. Rajagopal, Shyama. Blowing out chance of fire hazards. The Hindu. 30 April 2011. Accessed 1 April 2014. <http://www.hindu.com/pp/2011/04/23/ stories/2011042353880400.htm>. 8. Overloading may have caused short-circuit. The Times of India. 24 May 2012. Accessed 1 April 2014. <http://timesofindia.indiatimes.com/city/ vadodara/Overloading-may-have-caused-short-circuit/articleshow/13457101.cms>. 9. The National Building Code of India. Bureau of Indian Standards, 2005. 10. The International Building Code. International Code Council, 2012. 11. NFPA 101: Life Safety Code. National Fire Protection Association, 2012.


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Review of NBC 2005 NBC[9], abbreviation of the National Building Code of India, is a compilation of codes developed by the Bureau of Indian Standards. • NBC is an excellent reference for all officials involved in the construction of a building — architects, interior designers, engineers, planners, etc. • Apart from general considerations, many specific considerations are covered that apply to a variety of building types. • These considerations have been designed to optimize a variety of criteria such as life safety, comfort, aesthetics, etc. However, the focus of this thesis is limited to aspects of “interior design” in “commercial building types” that affect “building and life safety”, and therefore only the revelant parts of NBC are considered in the review presented below. The review uses the 2005 edition of NBC[9], and illustrates certain patterns in NBC that are evident throughout the codes, using only a few examples. As is the case with codes in general, NBC also provides direct specifications without explaining/illustrating the underlying concepts and why they are important; this adds to the need for this thesis. The specifications provided are quite detailed in some parts (e.g., signage), but not in some others (e.g., means of egress). NBC is mainly compiled from the architectural viewpoint, and gives very less emphasis on interior aspects. For example: • NBC does not require a practicing interior designer to be certified. Chances are high that uncertified professionals may hamper the safety of occupants. • Interior materials for furnishings and finishes are described very briefly in half a page, whereas these are presented thoroughly in other codes such as IBC[10] or NFPA 101[11]. Finally, NBC is difficult to comprehend and has some outdated/missing concepts, but other parts are exceptionally detailed. • NBC recommends 33 grade cement, which is very inadequate as of today. In fact, it is not available at most places. • §4.2.9 in Part 4 of NBC[12] specifies that fire doors should be provided at “appropriate places”, but “appropriate” is left undefined. • The number of exits required in a building should crucially depend on the number of users, but this is not the case in NBC! • Unlike most other codes[10,11], NBC does not specify any required separation between exits (see Section 3.2.3.2 of this thesis). • However, signage specifications are very carefully designed, keeping in mind the different types of signs used in practice. Overall, NBC is useful for interior designers, but may need further revisions to be at par with other codes and needs to include more interior aspects. Also, illustrating the concepts underlying the codes may aid its readers in learning the intention behind the codes. This may enhance their understanding of the codes, which may result in greater safety in buildings and of occupant lives.

12. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 26.


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Introduction

Proposal

Why do we have building codes? Why should a law regulate what one can or cannot do with one’s own property? The idea of having building codes originated from the need to create a safe and secure habitat for its occupants. Such regulations exist in order to ensure that one’s actions do not affect the well-being of others adversely. While building regulatory codes date as far back as to the eighteenth century BCE, they have evolved along with the evolution of the methods and technologies for building planning, designing, and construction. In India, the National Building Code (NBC) came into existence in 1970, and has been revised twice since then, in 1983 and again in 2005. So why are building mishaps piling up[1], even though building codes exist? In India, most of the building mishaps are caused due to fire hazards[2,3,1] and structural hazards.[4,5,6] Whereas structural hazards mainly fall under the domain of architects, civil engineers and on-site workers[7], the reasons behind fire incidents, such as loose electrical wiring[3,8,9], lack of enough fire extinguishing equipment[10], use of inadequate materials and finishes[9], etc., fall under the domain of interior designers (and related agencies)[7]. In general, construction projects nowadays require a multi-faceted team, where each professional/agency has different responsibilities in ensuring building and occupant safety. But in India, the task is a bit harder for interior designers mainly for two reasons: • While NBC India has detailed specifications and codes regarding various architectural specifications, the codes specify fewer details for interior specifications. • Also, as specified in NBC India[11], the interior designer is the only professional involved who is not required to be certified. Hence, chances are high that practicing individuals may be unaware of the hazards corresponding to some of the interior details, let alone the existing standards to protect against these hazards. What can be done to alleviate these issues? One approach might focus on raising awareness among the owners/tenants regarding the required safety standards in their own habitats; this would force the building officials to ensure that all safety standards are met during the construction and afterwards. A more bottom-up approach would suggest a further understanding of the key concepts based on building and life safety codes. This may in turn help the designers to easily evaluate all the risks associated with each decision they make and assess the alternatives accordingly.

Aim

Introduction

“To study and consolidate interior guidelines for commercial spaces in India and prepare an aid for conceptual understanding of these guidelines.”

Research Question Which important concepts and precautions do interior codes identify as critical to occupant safety and building hazard?


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Objectives 1. Investigate if there is need for detailed interior codes in India. a. Using examples of building mishaps caused by oversight in the design and/or execution of the interior or interior services. 2. Understand the interior guidelines given in the National Building Code (NBC) of India provided by the Bureau of Indian Standards. 3. Extract the codes related to building and life safety, and derive the key interior concepts that facilitate the understanding of such codes. 4. Contrast with global building codes such as the International Building Code (IBC, by the International Code Council) and NFPA 101 (by the National Fire Protection Association) 5. Outline the important interior concepts on which less emphasis is given in NBC India.

Scope and Limitations • This thesis focuses on concepts of interior design, understanding which may help in protection against various hazards. For the crispness of the thesis, only those hazards which immediately endanger life safety are studied. • The focus of this thesis is restricted to commercial building types in India for a detailed analysis. • Non-technical aspects of design such as aesthetics, reflection of cultural identity, etc. are not taken into consideration in this thesis. • This thesis is not intended to be a substitute for any codes or standards. Rather, the purpose of this thesis is to present an in-depth understanding of the interior concepts that are the key to such codes. • The codes cited in this thesis are for illustrative purposes. No part of the thesis is, by any means, the “final ruling”.  This thesis bears no liability for any codes, regulations, or standards cited. • This thesis does not judge the validity, applicability, or effectiveness of the codes cited. It only discusses the concepts important for building and life safety in the practice of interior design, including the concepts which may not be emphasized in NBC India. • The codes and concepts studied apply to the construction and alteration of buildings/structures erected after 1950 only. • This thesis does not study guidelines for maintenance of buildings/ structures and equipment used during construction/renovation.

Methodology • Literature Review oo Studying the core literature on the subject, such as books on interior design standards, the National Building Code (NBC) of India, the International Building Code (IBC), standards published by NFPA, etc., and if necessary, some tangential literature that gives a broader perspective. • Personal Discussions oo Discussing with experienced professionals and academic practitioners regarding the current status of interior standards in India, how well they are followed, how can they be better understood through


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illustration of the fundamental concepts, and what important information might be missing in the current interior standards. • Case Study oo After explaining the concepts derived from the codes, taking built environments as case studies, analyzing various safety-critical details, and highlighting connections and dependencies between various design decisions.

Relevance of the Study This thesis aims to provide an understanding of the basic concepts of interior design related to building and life safety in commercial spaces of India. A better understanding of these concepts may serve to create awareness among the owners and occupants of the space in terms of life safety. • To the practicing designers: As commercial spaces are usually large in scale, the design of such spaces involves paying attention to a plethora of interior concepts. This thesis may aid the designers to understand the importance of these concepts so that no detail important to public life safety is overlooked. • To the students: The conceptual understanding provided in this thesis may help the students learn the organization of the codes in general, and how to use them to better meet public health and life safety criteria. In this way, the thesis may help these future practitioners to enhance their understanding from a very early stage in their professional careers.

Citatation [1] Nair, R. R. Fire and Explosion Hazards. Industrial Safety Review, January 2013. [2] Rajagopal, S. Blowing out chance of fire hazards. The Hindu. 30 April 2011. Accessed 1 April 2014. <http://www. hindu.com/pp/2011/04/23/stories/2011042353880400.htm>. [3] Safety short-circuited. The Times of India, 11 December 2011. Accessed 1 April 2014. <http://timesofindia.indiatimes.com/city/ahmedabad/Safety-short-circuited/articleshow/11066137.cms> [4] 2013 Thane building collapse. Wikipedia. Accessed 1 April 2014. <http://en.wikipedia.org/ wiki/2013_Thane_building_collapse> [5] Cook, L., Yan, H., and Udas, S. Decorator responsible for building collapse, killing 61. CNN. 30 September 2013. Accessed 1 April 2014. <http://edition.cnn.com/2013/09/29/world/asia/mumbai-building-collapse/>. [6] Jeweller held for Borivli building crash. Times of India. 24 July 2007. Accessed 1 April 2014. <http://timesofindia. indiatimes.com/city/mumbai/Jeweller-held-for-Borivli-building-crash/articleshow/2228648.cms>. [7] Godsey, L. Interior Design: Materials and Specifications, Fairchild Books, 2008. [8] Nair, R. R. Electrical Hazards. Industrial Safety Review, October 2012. [9] Eureka Forbes. Now, prevent fire before it spreads! Industrial Safety Review, December 2012. [10] Nair, R. R. Equipment for Fire Protection. Industrial Safety Review, November 2013. [11] The National Building Code of India, Bureau of Indian Standards, 2005.

Introduction

Key Terms Alleviate: make (suffering, deficiency, or a problem) less severe. Comprehensive: complete; including all or nearly all elements or aspects of something. Consolidate: combine (a number of things) into a single more effective or coherent whole. Exposition:a comprehensive description and explanation of an idea or theory. Mishap: an unlucky accident. Overlook: fail to notice (something). Plethora: a large or excessive amount of (something).


How to Read This Thesis Please Note... • The interior design concepts derived in this thesis are restricted to the ones that affect building and life safety. In particular, aesthetic aspects of the design are not considered. Correspondingly, only safety-critical codes are cited. Other codes can be accessed from the relevant sections of the building codes as referenced in the appropriate parts of the thesis. • The thesis strongly follows the terminology and specifications of the National Building Code of India (NBC)[1] because the focus is on Indian commercial spaces. However, the concepts derived apply to commercial spaces in general. For better understanding and missing details in NBC, other codes such as the International Building Code (IBC)[2], codes by the National Fire Protection Association (NFPA)[3,4,5], and the ADA standards for accessible design[6] are also referred. A complete list of available codes is given in Appendix B of this thesis. • This thesis is not intended to be an addendum, replacement, or refinement to any laws, codes, regulations, guidelines, or standards. Rather, the purpose of this thesis is to present an in-depth understanding of the interior concepts that are the key to the codes concerning building and life safety. Some of the tables and specifications from building codes are partially restated only for explaining the concepts better and for the convenience of the reader. The reader should always refer to the appropriate building codes for the exact specifications applicable. • The concepts derived from the codes are illustrated with figures, wherever appropriate and/or required. • The thesis is an interpretation of the codes based on their intent and language. The interpretation adopted here may not exactly reflect the interpretation rendered by the authorities that published the codes. • The concepts covered in this thesis are by no means a complete list of possibilities, but rather the concepts that help understand most of the safety-related codes.

Notation • “§A.B.C[i]” means section A.B.C of citation [i] of the end notes provided at the end of the chapter. • “NBC” refers to the 2005 edition of the National Building Code of India[1] published by Bureau of Indian Standards (BIS). • “IBC” refers to the 2012 edition of the International Building Code[2] published by the International Code Council. • “NFPA” refers to the National Fire Protection Association. • “ADA accessibility standards” refer to the standards given in ADA Standards for Accessible Design[6] published by the United States Department of Justice. • “Good practice [A(B)]” or “Accepted standard [A(B)]” refers to a particular Indian Standard published by the Bureau of Indian Standards (BIS).

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NBC provides a list of standards at the end of each part. Good practice or accepted standard [A(B)] should be given in the list of standards at the end of Part ‘A’, at index ‘B’.

Things to Keep in Mind While Reading: • Words used in the present tense include the future; words stated in the masculine gender include the feminine and neuter; the singular number includes the plural and the plural, the singular. • References to chapter or section numbers should be construed as the chapter or section of this thesis, unless specified otherwise.

Introduction

• Measurements have been provided in metric system where NBC has been referred, but not when other codes are referred.

1. 2. 3. 4. 5. 6.

The National Building Code of India. Bureau of Indian Standards, 2005. The International Building Code. International Code Council, 2012. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. NFPA 70: National Electrical Code. National Fire Protection Association, 2012. NFPA 5000: Building Construction and Safety Code. National Fire Protection Association, 2012. 2010 Ada Standards for Accessible Design. United States Department of Justice, 2010.


Structure of This Thesis This thesis is organized in two parts overall. Part 1 of the thesis begins with a brief introduction and focuses on construction types (Ch.1) and occupancy classifications (Ch.2), which illustrate the basic concepts that help with understanding other concepts. Part 2 then focuses on the interior design aspects that are critical to building and life safety in commercial spaces. This includes building services (Ch.3) and interior environment (Ch.4). The thesis concludes with case studies that demonstrate how safety-critical interior details can be observed in real-world commercial built environments. Following is a brief introduction to each chapter that provides a high level summary of the concepts explained therein.

PART I: BUILDING BASICS Chapter 1 : Construction Types and Building Classification Why do we need to classify buildings? The need for explicit building requirements has been realized since many centuries. But today, there are an uncountable number of different types of structures erected, and it is infeasible to list down the specifications for each and every type of structure in the world. Thus, buildings are classified and the specifications are stated in terms of the classification. Construction types use crucial information about the structural elements of the buildings to classify them. Although architects usually determine the construction type before interior designers are involved, it is important for interior designers to have basic information about construction types because they influence various interior decisions such as deciding the fire resistance rating of the corridors, relocating walls, making changes to floors and ceilings, etc. Construction types also influence building renovation. Finally, together with occupancy classification (defined in Chapter 2), construction types influence maximum building height and floor area.

Chapter 2: Occupancy Classification Construction type alone is not sufficient to determine the level of risk associated with a building, and thus to safeguard public life safety. Occupancy classification is the other side of the coin. The occupancy type of a building or a space within a building vaguely describes how and by whom the space is used. The occupant load, i.e. the number of people that will occupy the space also plays a key role in determining the occupancy type. Sometimes, different spaces within the same building may be assigned different occupancy types. It is important for an interior designer to be aware of the occupancy types because they affect certain regulations regarding the means of egress, fire/smoke protection, detection, and extinguishing systems, furnishings and finish materials, plumbing fixtures, etc. This chapter presents an indepth understanding of the occupancy types, their identification, and their implications.

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PART II: LIFE SAFETY Chapter 3: Building Services Fire presents one of the greatest dangers to occupant lives. Combating the risk of fire involves the use of a variety of systems in synchronization. During normal use, the causes of fire can be diminished by using noncombustible materials and taking special care in electrical system. When fire occurs, compartmentation in the building contains fire/smoke, and slower their spread. In such emergencies, the detection system detects fire, and activates the alarm system and the extinguishing system (e.g., sprinklers), if required. As the alarm notifies the occupants of the emergency, the occupants use predetermined means of egress to evacuate the building. Exit marking and egress signage are provided and illuminated to facilitate the egress process. For these systems to be effective in ensuring occupant safety, it is important that each system works correctly. To ensure proper installation and working of systems such as sprinklers and mechanical ventilation, an interior designer may also need to know the corresponding basic plumbing and mechanical specifications as well. This chapter describes all of the abovementioned methods and the applicable considerations for fire protection and life safety.

Chapter 4: Interior Environment Two of the major aspects of interior environment that affect building and life safety are: 1) Interior Furnishings and Finishes, and 2) Signage. Combustible materials in furnishings and surface finishes contribute significantly towards the fuel load in a building. In case of fire, this may act as a boosting factor, leaving the occupants less time for evacuation, which shows that the choice of materials in furnishings and finishes is very critical for life safety. The material chosen should allow slower spread of flame across its surface and should not generate much smoke; in particular, it should not emit highly toxic smoke/fumes in presence of fire. On the other hand, signage system has two parts: egress signage (covered in Section 3.2) and outdoor display structures. Particularly, outdoor display signboards may present danger to pedestrians by falling on them, to drivers by causing distraction, or in some cases, to the occupants of the building as well by hampering their evacuation. Hence, the location, dimensions, weight, illumination, and materials of outdoor display signboards should also be chosen carefully.

Chapter 5: Case Study

Introduction

While the main body of the thesis focuses on the concepts of interior design that are critical to building and life safety, case studies are presented in this chapter that focus on observing the corresponding details in a commercial built environment. Note that the purpose of the case studies is not to evaluate the safety of any given place, but solely to illustrate which safety-critical details can be observed, where they can be observed, and how the interdependency between such details can be analyzed.


1

13

Construction Types and Building Classification

In This Chapter, 1.1 Construction Types

1.1.1 Mixed Construction Types 1.1.2 Importance of Construction Types in Interior Design

1.2 Building Height and Area Specifications

1.2.1 Basic Specifications for Building Parts

Earlier, in India and all over the world, buildings with larger size and population were associated with higher risk of life and property loss. Today, detailed understanding has revealed that the risks associated with a building are more accurately connected with the construction and the occupancy of the building. Hence, modern building codes such as NBC[1] directly express the specifications for a building in terms of its construction type and occupancy classification. This chapter describes the construction types and their importance in the practice of interior design.


14

Fire Resistance The number of hours an element of building construction can resist: 1. collapse, 2. penetration of flame and hot gases, and 3. temperature rise on the unexposed face up to a maximum of 180°C and/ or average temperature of 150°C.

1.1 Construction Types Construction types classify buildings according to the hazards presented by its structural elements. To ensure that hazards are minimized, construction types govern the types of materials, systems, and assemblies to be used in the structural elements of a building. It also governs the minimum hourly fire resistance ratings for these building elements. Fire resistance ratings play a crucial role in the building requirements because fire presents the greatest hazard to a building. In this sense, fire resistance ratings specify fire endurance requirements, and do not necessarily require the use of fireproof materials. The fire resistance properties of a material depend on how easily the material gets ignited, how long it burns once ignited, how quickly the fire spreads, and how much heat the burning generates. These affect the initiation and spread of fire and smoke within the building as well as to/from other buildings. Accordingly, materials are classified into non-combustible, fire resistant, limited combustible, and combustible. It would be safer if materials are checked against the required fire resistance ratings prior to their use, and that the assessment is made available to all concerned individuals (including the occupants). This thesis uses the same construction types as NBC[1] for the ease of explanation and reference to other codes. There are four basic construction types defined in NBC.[2]

Chapter 1 : Construction Types and Building Classification

Note: The fire-resistance requirements of a building also decrease as its distance from the adjacent buildings increases.

As Table 1.1 on the opposite page shows, fire protection requirements gradually drop as one goes from left to right (Type 1 to Type 4). For example, Type 1 is the most fire protective of all building types, and is therefore usually assigned to high-rise buildings because they have more fuel for fire (such as furniture, equipment, and paper/stationary) than other buildings. Additional concerns in high-rise buildings include infeasible evacuation of all the occupants within a reasonable time and inability of the fire department equipment to reach all the fire affected regions. On the other hand, Type 4 has almost no fire resistance requirement, and is usually used for small structures with low occupancy, e.g., small stores, shops, small offices and residences, etc. For interior and structural changes, the interior designer can determine (if needed) the fire resistance ratings of different materials based on their thickness (see Tables 2 to 18 of NBC[3] for detailed ratings). While it is unusual for multiple construction types to occur in a single building structure, it is possible. Next, mixed construction types are described, along with the specifications regarding their separation.

Firewall

1.1.1 Mixed Construction Types

A fire-resistance-rated wall having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the roof, with sufficient structural stability under fire conditions to allow collapse of construction on either side without collapse of the wall.

One example of a mixed construction type would be a medical office building adjacent to or on top of a parking garage. Different construction types should be separated from each other by a separation wall, in effect creating two or more separate buildings, as shown in Figure 1.1. This separation wall is known as a fire wall or party wall. A fire wall should usually extend from the foundation of a building through the roof to a parapet wall. Further, it should remain stable even if one side of the wall or building collapses during a fire. In cases such as a medical office building on top of a parking garage, the fire wall can be built horizontally (see Chapter 3 for further details).


15

Fire Resistance Ratings of Structural Elements (in Hours) Structural Element Type of Construction

No

Type 1

Type 2

Type 3

Type 4

4 2 4 1½ 4 1 4

2 1½ 2 1 2 1 2

2 1 2 1 2 1 2

1 1 1 1 1 1 2

 

4

2

2

2

 

2

2

2

2

 

2

2

2

2

 

1

1

1

1

 

1

1

1

1

   

1 ½

1 ½

1 ½

1 ½

Interior bearing walls, bearing partitions, columns, girders, trusses (other than roof trusses) and framing

i) Supporting more than one floor ii) Supporting one floor only iii) Supporting a roof only

4

2

2

2

3

1

1

3

1

1

11

Structural members support walls

 

3

1

1

12

Floor construction including walls

 

3

1

1

2

1

1

Roof construction

i) 5 m or less in height to lowest member ii) More than 5 m but less than 6.7 m in height to lowest member iii) 6.7 m or more in height to lowest member

1

1

1

1

0

1

0

0

  Exterior walls

a) Fire separation less than 3.7 m b) Fire separation of 3.7 m or more but less than 9 m c) Fire separation of 9 m or more 2 3 4 5 6 7 8 9

10

13

Fire walls Fire separation assemblies (like fire check doors) Fire enclosures of exitways, exitway hallways, and stairways Shaft other than exitways elevator hoistways Exitway access corridors Vertical separation of tenant spaces Dwelling unit separation Non-load bearing partitions

i) Bearing ii) Non-bearing i) Bearing ii) Non-bearing i) Bearing ii) Non-bearing  

Note: Although construction types are defined and described through fire resistance ratings, fire resistance and prevention are explained in Fire Protection and Life Safety section of Chapter 3 of this thesis.

Above : Table 1.1 Describes the required fire resistance ratings of different structural elements of a building in terms of the construction type of the building. Adapted from “The National Building Code of India” BIS, 2005. Part 4, p. 14.

Construction Types

1

 


16

Note that after a fire occurs in a building, the exposed building elements may be altered. While many noncombustible materials may appear to have endured the fire unchanged, continuous flame and heat may have changed the strength and structural makeup of such materials.

Right : Figure 1.1 Shows the separation of different construction types by a fire wall. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.187.

Chapter 1 : Construction Types and Building Classification

PROTECTED OR UNPROTECTED When discussing building limitations in the building code, the issue of protected and unprotected is often a source of confusion. Whether the construction of a building is considered protected or unprotected does not have anything to do with the use of an automatic sprinkler system. Instead, unprotected indicates that the structure or building elements of a building have not been treated in any additional way to increase their fire resistance beyond the natural characteristics of the materials. Protected indicates that the structural elements of a building have been treated to increase their fire resistance. This may include the use of noncombustible or limited combustible materials or fire-proofing materials to enclose or cover the elements of the structural assembly. Ultimately, a protected construction type provides more resistance to fire than the same construction type that is unprotected.

Combustible AND noncombustible material Four basic materials are generally considered noncombustible: steel, iron, concrete, and masonry. Their actual performance in the event of a fire, however, depends on how they are used. Occasionally they may require additional fire treatment or protection for extra strength and stability. For example, steel has a rapid loss of strength at high temperatures and is therefore often encased in concrete or covered in a protective coating. On the other side of the spectrum are combustible materials. These are materials that will continue to burn when the flame source is removed. Wood is a common combustible item. However, wood and other construction materials can be chemically treated to gain some amount of fire resistance. For example, chemically treated wood is called “fire-retardant treated wood” (also commonly known as FRTW). Wood can also be considered fire resistant if it is large enough in diameter. Heavy timber is considered to be fairly fire resistant because of its size. Typically, columns are required to be at least 8 × 8 inches (203×203 mm) and beams a minimum of 6 × 10 inches (152×254 mm). Heavy timber builds up a layer of char during a fire that helps to protect the rest of the timber.


1.1.2 Importance of construction types in Interior Design An interior designer always works in an “existing” building. Note that even a new building is considered existing at the stage when an interior designer is involved. But the limitations imposed by construction types and fire resistance ratings apply, not only to new buildings, but also to existing buildings. For example, an interior designer should not use wood-framed interior walls or ceilings in an existing Type 1 or type 2 building structure, but may use protected wood frames in the interior walls if the building has Type 3. In addition, it should also be ensured that appropriate regulations—which depend on the construction type—are followed when additions are made to a building, or when it is renovated. For this reason, it is important for an interior designer to be able to identify the type of a building.

17

Note: It would be helpful if the existing conditions are documented prior to the alteration and the construction type of the building is determined, so that a change of building type in the future and its consequences can be analyzed easily.

Professionals or authorities should always be consulted to determine the construction type of a building. However, it may be helpful to observe the fire-resistance of the following building elements. 1. 2. 3. 4. 5. 6. 7.

Structural frame Exterior bearing walls Interior bearing walls Exterior nonbearing walls and partitions Interior nonbearing walls and partitions Floor construction, including supporting beams and joints Roof construction, including supporting beams and joints

At this point, it is important to emphasize that no harm is caused by assuming a higher type (type 1 rather than type 2, etc.) because higher types have stricter requirements. Two important aspects of a building affected by its construction type are building height and area, which are described next.

The regulations on height and area of a building are determined by various factors such as its construction type, occupancy classification, location, etc. Even though the building size is usually fixed at the time of construction, these regulations play an important role in interior projects as well because they should be met even when additions are made to existing buildings. For example, if there is a need for larger building size, additional fire protection measures (e.g., installation of sprinklers) may be taken to upgrade the building’s construction type. Some of the factors influencing such regulations that are relevant for interior designers are outlined below. • Construction type. Stricter construction types use more noncombustible materials and are most protected, and therefore allow larger building sizes. For example, type 1 construction sometimes has no height limitations and few area limitations. • Occupancy classification. Some occupancy classes restrict building sizes and construction types. Number of occupants and their mobility also affects regulations on building height and area. • Sprinklers. Using automated sprinklers add to the fire protection of the building. Sometimes this may upgrade the construction type (or subtype) of the building, resulting in more allowance in terms of number of

Building Height and Area Building height is measured from the ground level till the average height of the roof, allowing pitched roofs, varying parapet heights, and rooftop equipments. Definition of building area excludes the thickness of exterior walls.

Note: Building height is usually represented in two ways — in absolute terms and in terms of the number of storeys. While the regulations governing the former depend on the construction type, the regulations governing the latter depend on the occupancy classification.

Construction Types > Building Height and Area Requirements

1.2 BUILDING HEIGHT AND AREa specifications


18

stories or floor area. • Fire walls. Fire walls divide a building into compartments, and limit the effect of fire in one compartment to another. The limitations then apply locally to each compartment, allowing larger overall building size.

1.2.1 Basic Specifications for Building Parts Depending on these factors, NBC[4] describes the height and size (width and area) specifications for various parts of a building such as habitable rooms, kitchens, bathrooms, store rooms, etc. The height of a space is usually measured from the surface of the floor to the lowest point of the ceiling. In case of air-conditioned rooms, the height is measured from the surface of the floor to the lowest point of air-conditioning duct or false-ceiling. Below, these parts are considered one-by-one, and the corresponding specifications are explained. It should be emphasized that only the specifications that may be important to an interior designer are described below. Habitable Room A room occupied or designed for occupancy by one or more persons for study, living, sleeping, eating, kitchen if it is used as a living room, but not including bathrooms, water-closet, compartments, laundries, serving and store pantries, corridors, cellars, attics, and spaces that are not used frequently or during extended periods.

1. Habitable Rooms • Height: The height specification of habitable rooms depends on its occupancy type. For residential, business, and mercantile buildings, the height of the room should be at least 2.75 m. In case of air-conditioned rooms, the height (recall that this is now measured from the surface of the floor to the lowest point of air-conditioning duct or false-ceiling) should be at least 2.4 m.* • Size: The size specification depends on the number of rooms in the part of the building. In case of a single room, the specifications for minimum width and minimum area are 2.4 m and 9.5 m2, respectively. In case of two rooms, the aforementioned specifications apply to the larger room, and the minimum width and area specifications for the smaller room are 2.1 m and 7.5 m2, respectively.

Chapter 1 : Construction Types and Building Classification

2. Kitchens • Height: The minimum height of a kitchen should be 2.75 m, except for the portion accommodating floor trap of the upper floor. • Size: The minimum size specification of a kitchen depends on whether a separate dining area is provided. In case a dining area is provided, the specification further depends on whether a separate store area is also provided. Below are the minimum width and area specifications respectively in each case. i) Separate dining and store area: 1.8 m and 4.5 m2. ii) Separate dining area only: 1.8 m and 5.0 m2. iii) No separate dining area: 2.1 m and 7.5 m2.

*

The corresponding specifications for educational and industrial buildings are 3.6 m in general and 3 m in cold or air-conditioned buildings.

• Additional specifications: Special safety-critical specifications that apply to kitchens include the need for an impermeable floor, and specifications on the area of window or ventilator opening. The area specification for the opening is described in terms of fraction of the floor area; this fraction depends on the weather — for dry hot climate it should be at least 1/10, for wet hot climate it should be at least 1/6, for intermediate climate it should be at least 1/8, and for cold climate, it should be at least 1/12. 3. Bathrooms and Water-Closets • Height: The height should be at least 2.1 m, for both bathrooms and water-closets.


• Size: The minimum width and area specifications are 1.2 m and 1.8 m2, respectively, for bathrooms, and 0.9 m and 1.1 m2, respectively, for water-closets. In case the bath and the water-closet are combined, the specifications change to 1.2 m and 2.8 m2, respectively. • Additional Specifications: At least one of the walls must have a window opening to external air with its width and area at least 0.3 m and 0.3 m2, respectively. The bathroom/water-closet should only be situated above and below other bathroom, water-closet, washing place, or terrace. Exception may be allowed if the bathroom/watercloset has a water-tight floor. Finally, it should not be connected to a kitchen/cooking space through doors, windows, or any other openings.

19

MEZZANINES A mezzanine is an intermediate floor level between the floor and the ceiling of a room or space. All mezzanines in a space together should occupy at most one-third area of the space. Mezzanine should have adequate headroom and should not be closed. It does not count as a storey but its construction type should be the same as the construction type of the space it is located in. The space containing a mezzanine should have at least one or two exits.

5. Parapet: Between 1.0 m and 1.2 m in height from the floor level. 6. Ledge or Loft: The height of a loft should be at most 1.5 m, and the loft should have at least 2.2 m head-room under it. To prevent interference with ventilation, the area of a loft in a habitable room should be limited to 25 percent of the floor area of the room. 7. Store Room • Height: At least 2.2 m. • Size: At least 3 m2, if provided in a residential building. 8. Chimneys: A chimney should be at least 0.9 m above flat roofs (in absence of parapet wall), and in case of sloping roofs, it should be at least 0.6 m above the part of the roof it penetrates. 9. Cabin: The minimum width and area specifications of a cabin are 1.0 m and 3.0 m2, respectively. Passages between divided spaces should be at least 0.75 m, and no space of the cabin should be farther than 18.5 m from an exit. Finally, the height of the cabin should be at most 2.2 m if the cabin does not derive direct lighting/ventilation from an open space/mechanical means.

Construction Type > Building Height and Area Specifications > Basic Specifications for Building Parts

4. Mezzanine Floor • Height: At least 2.2 m. • Size: At least 9.5 m2 (only applies if used as a living room. • Additional Specifications: A mezzanine floor should have adequate lighting and ventilation as per the standard of living, and should not interfere with the ventilation of the space above or under it. A mezzanine floor should not be closed or sub-divided, and should not be used as a kitchen.


20

10. Meter Rooms: The specification for meter rooms depends on the height of a building and its occupancy type. Independent and ventilated meter (service) room is required in buildings either with at least 15 m height or having educational, assembly, institutional, industrial, storage, or hazardous occupancy, or mixed occupancy with any of the previously mentioned occupancies having more than 500 m2 area on each floor require meter rooms. Further, such meter rooms should have a direct access from outside on the ground floor, and their doors should have a fire resistance rating of at least two hours.

Chapter 1 : Construction Types and Building Classification

11. Staircase: For staircases, the specifications state the minimum clear width, the minimum tread width and the maximum height of riser. These depend on the occupancy classification of the building. • Minimum width: Residential dwellings – 1.0 m (except row houses with 2 storeys, for which the requirement is 0.75 m), residential hotels and educational – 1.5 m, assembly and institutional – 2 m, and all other occupancies – 1.5 m. • Minimum tread: Residential – 250 mm, other occupancies – 300 mm. • Maximum riser: Residential – 190 mm, other occupancies – 150 mm. These should be limited to 12 per flight. • Minimum head-room: At least 2.2 m in any staircase and below the landing staircase.

End Notes 1. 2. 3. 4.

The National Building Code of India. Bureau of Indian Standards, 2005. Ibid. Part 3, p. 22. Ibid. Part 4, pp. 15-21. Ibid. Part 3, pp. 29-34.


2

21

Occupancy Classification

In This Chapter, 2.1 Occupancy Types

2.1.1 Occupancy Group and Subtypes

2.2 Mixed Occupancy Types 2.2.1 Accessory Occupancies

2.3 Occupant Load

The occupancy type of a building describes the type of usage and the type of users of a building or a space within a building. The occupancy type affects several safety requirements in a building such as means of egress, allowable height and area, and the construction type. For example, consider the means of egress. Hospitals, schools, and assembly halls require more effective means of egress to ensure safe and timely evacuation of all the occupants. In short, while the construction type describes the hazards presented by the building and its elements, the occupancy classification dictates the special requirements that emerge from the type and number of users. This chapter describes different occupancy types of commercial spaces, and various specifications that apply to these occupancy types.


22

2.1 Occupancy types Buildings or parts of buildings are assigned occupancy types based on their intended usage. Occupancy types affect various safety requirements such as the construction type, the allowable height and area, and means of egress. Many occupancy types also have various subtypes that refine this classification in order to allow for more specific requirements. Identification of occupancy type. The occupancy type is usually determined at the beginning of a project. This process involves analyzing various crucial risk factors in a building. While the major risk factors are related to the concentration and characteristics of the occupants (e.g., their mobility, age, and sometimes their familiarity with the space), some minor risk factors could be related to the spatial relationship between the space and the users (e.g., inadequate ventilation and low light levels). Table 2.1 gives the 9 occupancy types defined in NBC[1]; this is also the occupancy classification followed in this thesis. Some of the types also have subtypes, which will be discussed later in this chapter.

Right : Table 2.1

Group

Occupancy

Describes various occupancy types as per NBC.

Group A

Residential

Group B

Educational

Group C

Institutional

Group D

Assembly

Group E

Business

Group F

Mercantile

Group G

Industrial

Group H

Storage

Group J

Hazardous

Chapter 2 : Occupancy Classification

Note that the focus of this thesis is restricted to commercial spaces only. The spaces categorized as commercial[4] and their occupancy types (and subtypes wherever appropriate) are given in Table 2.2. Most of these spaces fall under three major occupancy types (Assembly -- Group D, Business -- Group E, and Mercantile -- Group F). Hence, the rest of the chapter will solely focus on these occupancies. Caution: It should be noted that while NBC[1] assigns consecutive letters to occupancy types, other codes such as IBC[2] and NFPA[3] assign the first letter of the name to the type (i.e., A for Assembly, E for Educational, etc.). Therefore, while Type A is used for Residential occupancy in NBC, it is used for Assembly occupancy in IBC. The designers should keep this in mind when referring to other codes.

Next, these three occupancy types and their relevant subtypes that include commercial buildings are described.


23 COMMERCIAL SPACES

Left : Table 2.2

Type of Building

Occupancy Type

Subtype

Auction house

Assembly (Group D)

D4

Bank

Business

(Group E)

E1

Bar

Assembly (Group D)

D4

Casino

Assembly (Group D)

D1/D2

Stock exchange

Business

E3

Market

Mercantile (Group F)

F1/F2

Nightclub

Assembly (Group D)

D3/D4

Office building

Business

(Group E)

E1

Restaurants

Assembly (Group D)

D6

Shops/Stores

Mercantile (Group F)

F1/F2

Shopping mall/center

Assembly (Group D)

D6

Supermarket

Mercantile (Group F)

F2

Convention center

Assembly (Group D)

D1/D2

(Group E)

Describes various types of buildings that are classified as commercial spaces[4], the occupancy type they fall under, and the specific subtypes applicable. [4] Xing, Rihan. Commercial Space. H. K. Rihan International Culture Spread, Hong Kong, 2009.

Beyond the scope of this thesis: Gas station

Hazardous (Group J)

Hotel

Residential (Group A)

Warehouse

Storage

(Group H)

Note 1: While gas stations, hotels, and warehouses are considered commercial spaces,[4] they are excluded here because they fall under Hazardous (Group J), Residential (Group A), and Storage (Group H) categories respectively, and including these categories is beyond the scope of this thesis. Note 2: Various specifications applicable to these spaces are further elaborated in the Fire Protection and Life Safety section of Chapter 3 of this thesis.

2.1.1 Occupancy Group and Subtypes

1. Group D – Assembly Occupancy “§3.1.5[5], Any building or part of a building where at least 50 people gather for amusement, recreation, social, religious, patriotic, civil, travel and similar purposes are assigned Assembly occupancy type. Examples of such buildings include theatres, motion picture houses, assembly halls, auditoria, exhibition halls, museums, skating rinks, gymnasiums, restaurants, places of worship, dance halls, club rooms, passenger stations and terminals of air, surface and marine public transportation services, recreation piers and stadia, etc. See Figure 2.1 for examples of buildings with Assembly occupancy. Distinctive characteristics of these spaces include a large number of occupants, low light levels (in some cases), occupants’ lack of familiarity with the surroundings, and potential panic in case of emergency. Due to these risk factors, additional safety precautions may apply to buildings with Assembly occupancy.

Occupancy Types > Occupancy Group and Subtypes

The three major occupancy types and their relevant subtypes[1] that fall within the scope of this thesis are described below.


24

a. Subdivision D-1: This includes any building primarily meant for theatrical or operatic performances and exhibitions and which has a raised stage, proscenium curtain, freed or portable scenery or scenery loft, lights, motion picture houses, mechanical appliances or other theatrical accessories and equipment and which is provided with fixed seats for over 1000 persons. b. Subdivision D-2: This includes any building primarily meant for use as described for subdivision D-1, but with fixed seats up to 1000 persons. c. Subdivision D-3: This includes any building, its lobbies, rooms and other spaces connected thereto, primarily intended for assembly of people, but which has no theatrical stage and for cinematographic accessories and has accommodation for 300 persons or more, for example, dance halls, night clubs, halls for incidental picture shows, dramatic, theatrical or educational presentation, lectures or other similar purposes having no theatrical stage except a raised platform and used without permanent seating arrangement art galleries exhibition halls, community halls, marriage halls, places of worship, museums, lecture halls, passenger terminals and Heritage and Archeological Monuments. See Figure 2.1 a.

a.

b.

d. Subdivision D-4: This includes any buiIding primarily intended for use as described in subdivision D-3, but for less than 300 persons with no permanent seating arrangements. See Figure 2.1 b and c. N

c.

e. Subdivision D-5: This includes any building or structure permanent or temporary meant for assembly of people not covered by subdivisions D-1 to D-4, for example, grandstands, stadia, amusement park structures, reviewing stands and circus tents. f. Subdivision D-6: This includes any building for assembly of people provided with multiple services/facilities like shopping, cinema theatres and restaurants, for example, multiplexes. g. Subdivision D-7: This includes any building or structure permanent or temporary meant for assembly of people not covered by D-1 to D-6, for example, underground or elevated railways.

Chapter 2 : Occupancy Classification

Above : Figure 2.1 Shows examples of buildings with Assembly occupancy. a. Auditorium - Subdivision D-3 b. Restaurant - Subdivision D-4 c. Church - Subdivision D-4 Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.21.

2. Group E РBusiness Occupancy Ҥ3.1.6[6], Business occupancy type is assigned to a building or a part of a building where the main purpose of use is transaction of business. This includes buildings used for keeping of accounts and records, and similar purposes, other than that covered by Group F РMercantile Occupancy, professional establishments, service facilities, etc. City halls, town halls, court houses and libraries should be classified in Group E so far as the principal function of these is transaction of public business and keeping of books and records. But a city hall that has a large assembly area may be assigned Assembly occupancy type, or a mixed occupancy type. Parts of buildings such as a small storage or supply area, break rooms, etc. are included as well.


See Figure 2.2 for examples of buildings with Business occupancy. In general, Business occupancy is one of the lowest risk occupancy classes due to the low concentration of occupants, their relative familiarity with the environment, and their general alertness. Buildings included in Business occupancy are further classified into various subtypes as follows.

25 Below : Figure 2.2 Shows examples of buildings with Business occupancy.

a. Subdivision E-1: Offices, banks, and professional establishments such as offices of architects, engineers, doctors, lawyers and police stations. b. Subdivision E-2: Laboratories, research establishments, libraries and test houses. c. Subdivision E-3: Computer installations. d. Subdivision E-4: Telephone exchanges. e. Subdivision E-5: Broadcasting stations and T. V. stations. 3. Group F РMercantile Occupancy Ҥ3.1.7[7], Mercantile occupancy type includes any building or part of a building, which is used as shops, stores, market, for display and sale of merchandise, either wholesale or retail. Precaution should be taken when assigning codes to groups of retail stores. Each store may individually be assigned Mercantile occupancy type. But if these stores are part of a large mall, which typically falls under Assembly D6 occupancy type, the corresponding assembly specifications should be followed as well.

b. c.

produced in any form without permission from the publisher, except fair uses permitted under U.S. or applicable copyright

a. Subdivision F-1: Shops, stores, and departmental stores markets Mercantile Group M 2 with area up to 500 m . Uses in these groups are fairly self-explanatory. The occupancy group includes incidental storage, which will be regulated per the mixed Subdivision F-2: Shops, stores, and departmental stores use provisions in § 508. Accessorymarkets occupancies are regulated by § 508.2 and must still be indiwith area more than 500 m2. vidually classified. Larger storage areas would be classified as Group S. Typically for larger combinations of M and S occupancies, the nonSubdivision F-3: Underground shopping centers, and storage and separated provisions of § 508.3 are used.

service facilities incidental to the sale of merchandise and located Most retail facilities, no matter what merchanin the same building. dise they sell, fall into this occupancy. There are

limits to the quantities of hazardous materials that may be stored in mercantile occupancies While identifying occupancy type in the beginning, one should also consider without being classified as a Group H occupancy. possible change in space usage in the future. ForThese example, a part of414.2.5(1). an office limits are shown in Table

space that is also going to be used as a conference room in future should be considered as an Assembly space rather than a Business space, and the corresponding code specifications should be followed to ensure safety over time. Finally, multiple occupancy types may be required when different spaces in a building are used differently or when shared public spaces host occupants of different characteristics.

Below : Figure 2.3 Shows examples of buildings with Mercantile occupancy.

Occupancy Types > Occupancy Group and Subtypes

See Figure 2.3 for examples of buildings with Mercantile occupancy. Mercantile buildings are further subdivided as follows.


26

2.2 Mixed Occupancy Types Sometimes, different types of usage in a building may lead to two or more occupancy types within the same building (see, e.g., Figure 2.4); in fact, this is more common than a building with a single occupancy. For example, hotels typically fall under Residential occupancy type. But today most large hotels have restaurants, indoor pools, exercise rooms, etc., which should be assigned Assembly occupancy type. Because different occupancy types bear different safety requirements, the specifications for a building with mixed occupancy types are somewhat more complicated. Crucially, they depend on whether the different occupancies are separated or non-separated. Spaces with different occupancies are called separated if there are partition(s) (walls, floor, and/or ceiling) between the spaces with certain fire-rating as specified by the relevant codes. While the specification of fire-rating for the separating wall/floor/ceiling is 4 hours in NBC[8], other codes such specify more fine-grained specifications which take into account the occupancy types separated by the partitions (see, e.g., the detailed occupancy-type-based separation specifications in Table 508.4 in IBC[9] and Tables 6.1.14.4.1(a) and 6.1.14.4.1(b) in NFPA.[10] Finally, in case of separated spaces with different occupancies each space should meet the safety requirements corresponding to its own occupancy type. However, if the different occupancies are not separated, the combined space should follow the safety requirements corresponding to the most stringent occupancy type. OCCUPANCY CLASSIFICATIONS AND LOADS

69

Right : Figure 2.4

Chapter 2 : Occupancy Classification

Shows mixed occupancy types on a single floor and across multiple floors. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.69.

Figure 2.5 Mixed Occupancies: Horizontally and Vertically (1 square foot = 0.0929

Note: Walls square are used typically when the occupancies are adjacent to each other horizontally (on the meter) same storey/level, whereas floor and/or ceiling is used for separation when they are adjacent vertically (on two different storeys/levels)

there istrade-off: no rated separation the occupancies, it is considered and This presentsWhen a critical eitherbetween to create a fire-rated separation by the IBC as a non-separated mixed occupancy. (This term is not used by the Note enjoy theNFPA.) benefits oftheonly havingare toconsidered meet the requirements of each occuThe term mixed multiple When occupancies non-separated, both occupancies occupancy is unique to the must the requirements stringent occupancy classification, pancy type inthen its meet respective space,oforthetomost omit the fire-rated separation but NFPA. Although similar to including construction type, allowable area, finishes, and exiting requirements. non-separated mixed then having to meet the strictest requirements (in terms of construction For example, in Plan B of Figure 2.6, the Mercantile (M) and the Assembly (A-2) occupancies in the IBC, a mixed multiple occupancy type, areaoccupancies limitations, etc.) inbythe whole space. The optimal decision are separated a partition only for visual reasons and so are consid- may includes a wider variety of ered non-separated. In this case, the more stringent Assembly requirements vary from project to project. Occupancy separation may not be requiredbuilding in scenarios. be applied to the entire area of the building, including the gift shop. a special would case described next. Many aspects can influence the choice to treat a mixed occupancy as separated or non-separated. Constructing rated assemblies for separation can be expensive or undesirable to the design, but having to meet the most stringent exiting requirements, construction type, or area limitations for the whole building or space may limit the design unnecessarily. You will have to consider these


2.2.1 Accessory Occupancies

Ҥ508.2[11], Accessory occupancies are those occupancies that are ancillary to the main occupancy of the building or portion thereof. To put simply, accessory occupancies are assigned to very small spaces with different usage than the usage of the building otherwise (see Plan B in Figure 2.5). These spaces usually do not play a key role in the core function of the building. The following characteristics and considerations apply to accessory occupancies.

27 Note: The definition of accessory occupancies is adapted from IBC[11] because the concept of accessory occupancies or requirements specific to such occupancies are not mentioned in NBC.[1]

• They typically do not occupy more than 10% of the building area of the story. • Their occupancy classification is identified individually. • Certain area and height limitations may apply specifically to accessory occupancies. • They are typically not required to be separated from other spaces. A few exceptions may include some of the high hazard and institutional occupancies, for example, separation of incidental accessory occupancies (see the key note for definition) may need additional safety considerations. ❏

THE CODES GUIDEBOOK FOR INTERIORS

Left : Figure 2.5 Shows accessory occupancy and incidental use areas. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.66.

Figure 2.3 Incidental Use versus Accessory Occupancies (1 square foot = 0.0929 square meter)

INCIDENTAL USE an accessory use, the two areas will not have to be designed under considered separate occupancy requirements. Sometimes there are several smaller uses occurring within a larger occupancy Certain uses are usually hazardous within any occupancy type. They are called incidental use areas. Typically, these classification, and all are located in the same building. An example would be a spaces arelarge relatively small the rest of A the discount store,compared like the oneto shown in Plan of building. Figure 2.4. For Thisexample, particular the storage room within a preschool store has a bakery, photo shop, salon,in and snack as part of itswould space. Inbe considered an incidental use area facility (Educational occupancy type)hair shown Plan A bar of Figure 2.5

within the building whose primary use areas are classrooms and office areas. Other examples include boiler rooms, furnace rooms, and other spaces containing hazardous items. The codes sometimes have special specifications for incidental use areas, mostly additional fire and smoke protection specifications.

Occupancy Types > Mixed Occupancy Types

66


28

2.3 Occupant Load

Note : The actual number of occupants should be used in further calculations (e.g., in determining means of egress) if and only if it exceeds the occupant load calculated from the codes using the occupant factor.

The occupant load of a building or a part of a building is the number of people that can safely use the space. The occupant load is usually determined at the beginning of a project, together with the occupancy classification. In fact, the occupant load may sometimes be required to determine the occupancy classification. For example, a restaurant with an occupant load of less than 50 should be assigned Business occupancy type, whereas a restaurant with an occupant load of more than 50 should be assigned Assembly occupancy type. The occupant load is a function of both the size of a space and the type of the space. The explicit relation is described in the following formula. Occupant load = Floor area (sq. ft. or sq. m.) / Occupant factor

LOADS: The occupant load should not be confused with two other types of design loads required by the codes—dead loads and live loads. Dead loads include all permanent components of a building’s structure, such as the walls, the floors and the roof. Live loads, on the other hand, include any loads that are not the actual weight of the structure itself, e.g., interior elements such as people, furniture, equipment, appliances, and books, weight due to exterior elements such as wind, rain and flood, and snow. These loads affect the design of the structure of the building. The loads are calculated by the engineers during the initial design and construction of a building. These calculations account for possible changes in the loads during the normal use of the building, e.g., varying number of people, relocation of interior walls, etc. Still, proposals for major changes require re-examination of the live loads by the engineers. Such proposals include adding a wall that is substantially heavier than a standard wall, creating a filing area or a library that concentrates the weight at one point, adding a heavy piece of equipment, and adding an assembly seating area in an existing room.

OCCUPANT LOAD FOR FIXED SEAT SPACES:

Chapter 2 : Occupancy Classification

Some buildings, typically in Assembly occupancy type, use fixed seating arrangements. Examples include restaurants, café, auction houses, etc. The seats are considered fixed if they are not easily moved and/or if they are used on a more permanent basis. In this case, the actual number of seats is counted instead of using the standard formula in order to calculate the occupant load. While each armed chair only hosts a single occupant, continuous seating such as benches, booths, bleachers, and pews may host multiple occupants. One occupant per 18 inches in case of benches and per 24 inches in case of booths should be considered to calculate the number of occupants the seating may host.

The occupant factor is the space required for each individual occupant to safely occupy a space. Occupant factors for spaces of different occupancy classifications are specified in Table 20 of NBC.[12] This table is reproduced as Table 2.3 for the convenience of the reader. More fine-grained specifications for the occupant factor may be found in other codes, e.g., see Table 1004.1.2 in IBC.[13]


Left : Table 2.3

Occupant Load SI No. (1)

Group of Occupancy (2)

Occupant Load, Floor Area in m2/Person (3)

i)

Residential (A)

12.5

ii)

Educational (B)

4

iii)

Institutional (C)

15 (see Note 1)

iv)

Assembly (D) a) With fixed or loose seats and dance floors

0.6 (see Note 2)

 

b) Without seating facilities including dining rooms

1.5 (see Note 2)

Mercantile (F)

The table lists the occupant factors for various occupancy groups in different situations. Adapted from “The National Building Code of India”, 2005, BIS, Part 4, p. 27.

 

 

v)

29

 

 

a) Street floor and sales basement

3

 

b) Upper sale floors

6

vi)

Business and industrial (E&G)

10

vii)

Storage (H)

30

viii)

Hazardous (J)

10

Note 1: Occupant load in dormitory portions of homes for the aged, orphanages, insane asylums, etc., where sleeping accommodation is provided, shall be calculated at not less than 7.5 m2 gross floor area/person. Note 2: The gross floor area shall include, in addition to the main assembly room or space, any occupied connecting room or space in the same storey or in the storeys above or below, where entrance is common to such rooms and spaces and they are available for use by the occupants of the assembly place. No deductions shall be made in the gross area for corridors, closets or other sub-divisions; the area shall include all space serving the particular assembly occupancy.

• If different parts of a space have multiple uses, the occupant load for each is calculated and added together. However, if the same space is used differently (e.g., over time), then maximum of the occupant load of the different uses is taken. • If multiple spaces have exits into a common area (e.g., corridors, stairs, exits, etc.), the occupant load of the shared area is determined by adding the number of occupants who will be using it. oo Further, in this case the occupant factor corresponding to the strictest occupancy type should be used. Implications of the occupant load. In addition to determining the number of occupants that are allowed to occupy the space at any given time, the occupant load also gives the number of occupants for which adequate means of egress should be provided. Hence, the occupant load determines the means of egress codes applicable to a space (see, e.g., Table 21 of Part 4 of NBC[14] for codes on the required width of the corridors and Table 22 of Part 4 of NBC[15] for codes on the maximum travel distance).  

Occupancy Types > Mixed Occupancy Types > Occupant Load

Special considerations. The calculation of occupant load requires certain special considerations.


30

Chapter 2 : Occupancy Classification

End Notes 1. The National Building Code of India. Bureau of Indian Standards, 2005. 2. The International Building Code. International Code Council, 2012. 3. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. 4. Xing, Rihan. Commercial Space. H.K. Rihan International Culture Spread, Hong Kong, 2009. 5. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 10. 6. Ibid. Part 4, p. 11. 7. Ibid. Part 4, p. 11. 8. Ibid. Part 4, p. 23. 9. The International Building Code. International Code Council, 2012. p. 103. 10. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. pp. 46-47. 11. The International Building Code. International Code Council, 2012. p. 101. 12. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 27. 13. The International Building Code. International Code Council, 2012. p. 241. 14. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 27. 15. Ibid.


There is certainly a risk ...

That if you want to write down all the risks, no one will read it anymore !

â&#x20AC;&#x153; Safety is something that a lot of people learn by an ACCIDENT â&#x20AC;?


32

PART II : LIFE SAFETY


3

33

Building Services Building services are very important part of interior design. Major building services include plumbing, mechanical, and electrical systems. When viewed from the building and life safety perspective, fire protection and means of egress are equally, or perhaps more important. In fact, plumbing, mechanical, and electrical systems also have certain aspects that are directly related to fire hazard. Combating fire hazard is achieved in three stages. 1. Preventing fire from occurring, and controlling its spread when it occurs â&#x20AC;&#x201D; achieved through the use of noncombustible materials and compartmentation, 2. Detecting and extinguishing fire in its early stages through the use of detection and extinguishing systems, and 3. Facilitating quick and safe evacuation of the occupants by using an alarm system, and providing means of egress and proper signage. Section 3.1 discusses fire prevention, detection, and extinguishing systems. Section 3.2 discusses means of egress and how to facilitate egress. Section 3.3 briefly outlines basic plumbing and mechanical considerations for sprinkler and ventilation systems because these systems help with protection against fire and smoke. Section 3.4 focuses on safe installation and use of the electrical system as electrical hazard is among the major causes of fatal fires.

In This Chapter, 3.1 Fire Protection and Life Safety

..... 34

3.2 Means of Egress

..... 56

3.3 Plumbing and Mechanical Systems

..... 77

3.4 Electrical Systems

..... 83


34

3.1 Fire Protection and Life Safety

In This Part, 3.1.1 Fire Zones 3.1.2 Fire Protection Systems 3.1.3 Passive Systems 3.1.3.1 Compartmentation in a Building

3.1.3.2 Opening Protectives 3.1.3.3 Through Penetration Protectives

3.1.4 Active Systems 3.1.4.1 Detection Systems

3.1.4.2 Alarm Systems 3.1.4.3 Extinguishing Systems

Chapter 3 : Building Services

This section describes various systems for preventing, detecting, and extinguishing fire. Fire prevention systems focus on eliminating the causes of fire as well as controlling its spread if it occurs. These are usually passive systems, which are simply there (e.g., a fire rated wall), and do not need to be engaged separately. On the other hand, fire detection and extinguishing systems are active systems which need to be engaged when fire occurs. The primary purpose of all these systems is to reduce panic and allow sufficient time for the occupants to evacuate. However, a secondary purpose is also to minimize property loss (including building collapse) due to fire. Earlier building codes only focused on fire, but it is now clear that smoke can be just as much or possibly more deadly than fire. The reason is that it travels fast, causes asphyxiation, makes egress difficult, and sometimes it is toxic as well. Hence, protection against smoke is equally important. Consequently, this section outlines various systems for protection against both fire and smoke, and various considerations for these systems that contribute towards building and life safety.


35

3.1.1 FIRE ZONES The level of fire protection required in a building crucially depends on its construction type and occupancy type. At a higher level, NBC[1] defines various “fire zones” that demarcate a city or area based on the fire hazard inherent to the buildings in the area. There are three fire zones, which restrict the allowed construction types and occupancy types, as given in Table 3.1.1.

Fire Zone

Fire Zone No. 1

Fire Zone No. 2 Fire Zone No. 3

Allowed Construction Types 1, 2, 3, or 4

1, 2, or 3 1 or 2

Allowed Occupancy Types

Residential (Group A) Institutional (Group C) Assembly (Group D) Small Business (Group E-1) Mercantile (Group F) Business (Groups E-2 to E-5) Industrial (Groups G-1 and G-2) High hazard industrial (Group G-3) Storage (Group H) Hazardous (Group J)

Left : Table 3.1.1 Describes allowed construction types and occupancy types in different fire zones.

Note : Temporary buildings and structures are only allowed in Fire Zones No. 1 and 2.

3.1.2 FIRE PROTECTION SYSTEMS

Passive Systems: Passive (prevention) systems focus on preventing and/or containing fires. Once in place, they do not need to be “activated” in case of fire. Examples include: 1. Fire and smoke barriers and partitions (e.g., walls, floors, ceilings), 2. Opening protectives (e.g., windows, doors), 3. Through-penetration protectives (e.g., firestops, draftstops, dampers), and 4. (Fire resistance of materials used in) finishes and furniture (e.g., wall coverings, finish floor materials, upholstered pieces, mattresses, and similar elements). Active Systems: Active systems need to be activated to work against the fire. Examples include: 1. Detection systems (e.g., detectors, fire alarms, and communication systems), 2. Extinguishing systems (e.g., fire extinguishers, fire hoses, and sprinkler systems), and 3. Emergency lighting (this is covered in Section 3.2).

Fire Protection and Life Safety > Fire Zones > Fire Protection Systems

Protection against fire is achieved through the combined use of multiple systems, which can be classified into passive, active, and exiting systems as follows.


36

Exiting Systems: Exiting systems assist and direct occupants to a place of safety. These are covered in Section 3.2. Examples include: 1. Means of egress (e.g., corridors, exits, stairs, ramps, and similar components), and 2. Exit communication systems (e.g., signage, audible and visual communication). Fire protection and means of egress are particularly important in high-rise buildings; see Annex C and Annex E of Part 4 of NBC[2] for additional specifications in this case. Automatic sprinkler systems provide major protection against both fire and smoke, and therefore their use relaxes many code specifications. The chapter now proceeds by first describing passive systems for fire protection.

3.1.3 PASSIVE SYSTEMS By using the right assemblies such as fire walls, fire barriers and partitions, smoke barriers and partitions, opening protectives, and through-penetration protectives, an interior designer can help create “compartmentation”, which can contribute to overall fire safety. Each of the abovementioned types of assemblies is described thoroughly in the following.

3.1.3.1 Compartmentation in a Building Passive fire and smoke protection systems mainly focus on compartmentation, i.e. separation of areas in a building to control the spread of fire and smoke. Crucially, note that the assemblies that prevent the spread of fire do not necessarily control the spread of smoke. Hence, controlling the spread of smoke requires special care. Next, various types of assemblies that can be used for compartmentation are described in detail. METHODS

Chapter 3 : Building Services

Note : Another function of fire walls is to support one side of the building even if the other side falls down during an emergency. Therefore, fire walls usually have a separate foundation and extend to the roof. Sometimes, they also extend beyond the exterior walls or project through the roof (i.e., parapet walls).

Fire Walls: Fire walls, also known as party walls, are used to vertically separate different parts of a single building or to separate two different buildings. Areas separated by a fire wall act as different “buildings” altogether for the purpose of codes. Hence, the code restrictions apply on the separated areas individually. For example, if the design for a factory exceeds its allowable area, fire walls can separate it into two smaller areas that fall within the allowable area limitations.

See Section 2.2 of this thesis for the required fire-resistance rating of separating fire walls. While fire walls may not be of much importance to interior designers (because they are planned and built during the initial construction), the designer may need to determine their fire-resistance rating if any changes are required (e.g., adding a door).

Fire/Smoke Barriers and Partitions: Fire/smoke barriers and partitions are used restrict the spread of fire/smoke and hot gases. Unlike fire walls, the areas separated are not considered different “buildings” by the codes. For both fire and smoke, the barriers and partitions can be horizontal or vertical; they could be wall, ceiling, or floor assemblies. However, there are certain differences between barriers and partitions. Usually, partitions are less restrictive than barriers, and therefore provide less protection.


• While a vertical/horizontal barrier should extend to the roof/exterior wall, a partition can stop at a rated ceiling or wall, as shown in Figure 3.1.3.1 A. When fire partitions end at another assembly, additional fireblocking may be required at the joint. See Section 3.1.3.3 for further details on fireblocking. Smoke barriers should also be sealed with fire rated assemblies on both ends. • Barriers provide full enclosure whereas partitions do not. Therefore, walls, floors, and ceilings adjoining a fire barrier should have the same fire rating, but this does not apply to a fire partition. Also, smoke barriers need fire rating while smoke partitions typically do not. • Both fire barriers and partitions should have limited openings (e.g., doors and windows), but the specifications are stricter in barriers. If the barrier/partition is fire rated, its openings should be fire rated too. Fire partitions are important for interior designers because adding a new fire rated wall is very common in interior projects, and this may not have the same rating as its adjoining floor or ceiling. Thus, it may act as a fire partition but not a fire barrier. Changes to existing assemblies (e.g., relocation, new finishes, addition of wiring or cabling) may also affect the level of protection. The specifications for barriers/partitions depend on the intended use, the occupancy classification, and whether an automatic sprinkler system is installed. The most common uses of fire/smoke barriers and partitions are described next. See Figure 3.1.3.1 A for an illustration of some of the ways in which fire/smoke barriers and compartments are used.

37

Note : Smoke partitions may have penetrations for speakers, recessed lighting, diffusers, and similar ceiling elements. These are typically not allowed in smoke barriers. In case of penetrations, extra specifications may be given in the codes for the type of door used, use of automatic release door closers, etc.

HOW SMOKE TRAVELS

• • • • •

Buoyancy: Heat during fire makes the smoke less dense, which increases its buoyancy. At a certain point, the smoke is forced up through any available leakage paths to the floor above and to adjacent areas. Expansion: Fire is usually coupled with emission of heated gases that expand and create pressure, forcing the smoke to move. HVAC: HVAC system can become a means of transport for the smoke. It may even supply air to fire which can create more smoke. Stack effect: Cold outside air forces an upward movement of air within building shafts such as stairwells, elevators, mechanical shafts, etc. When outside air is warmer, it creates a downward flow. In any case, such flows can aid the smoke to move long distances. Wind: Finally, open windows during fire can supply air to fire, and can also force the wind to go from one space to adjacent space.

To prevent the spread of smoke due to the factors mentioned above, it is important to use smoke barriers and partitions.

Fire Protection and Life Safety > Fire Protection Systems > Passive Systems

For a better understanding of smoke control systems and how they work, it is important to know how smoke moves. There are five major driving forces[3]:


38 Fire Walls Continuous from foundation to roof. Create separate buildings

Fire Barriers Occupancy separation Interior exit stairway

Fire Partitions Fire rated spaceAND separators FIRE-RESISTANT MATERIALS ASSEMBLIES and corridors

Right : Figure 3.1.3.1 A Shows various methods and uses of fire/smoke barriers and partitions. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.100.

187

tion, and if the space or building has sprinklers. (The sprinkler system must meet the current code requirements.) The most common uses of fire barriers and partiHorizontal Assemblies tions for compartmentation are described next.

Horizontal fire barriers near fire barriers/partitions and Fire Areas smoke barriers Fire barriers and exterior walls are used within a building to separate one area

from another, creating two or more fire areas. (When a fireSmoke wall is Barriers used to create Note separate buildings, the buildings are considered separate fire areas, as well). Fire Some jurisdictions require Fire rated, horizontal or rating for a wall areas are most often required within a single occupancy type to provide the assembly to be indicated on compartmentation. For example, fire areas can be used tovertical divide a large factory the wall somewhere above building into separate areas. The separate fire areas may allow one area of a build- the finished ceiling. ing to be sprinklered and another to remain unsprinklered, as shown in the Plan at the top of Figure 5.4. (This is different than the example of using a fire wall to

Right : Figure 3.1.3.1 B Shows sprinkler specifications in cases of fire areas separated by a fire wall or barrier. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.187.

Chapter 3 : Building Services

Note : In smoke compartments, additional ventilation is required due to full enclosure. This would be activated by a smoke detector in case of fire. Smoke compartments should have sprinklers and a temporary area of refuge into the next compartment (not considered an exit).

USES

Fire Areas and Smoke Compartments: These are areas separated by fire/smoke barriers and possibly exterior walls. Fire areas are often used to provide compartmentation within a single occupancy. For example, hazardous material stored within storage occupancy may be contained within a fire area. This would allow only the fire area to be sprinklered (and the restand Vertically Figure 5.4 Fire Areas: Horizontally of the occupancy to be unsprinklered), as shown in Figure 3.1.3.1 B. Smoke compartments are needed in special cases when smoke presents a special danger. An example would be a stairwell with a refuge area, where the stack effect may present the danger of smoke.


Tenant Separation: Typically, the spaces of different tenants need to be

fire-separated. For example, different businesses in a commercial building should be separated by fire-rated walls. In some cases, separation using fire partitions instead of fire barriers may be allowed.

Incidental Use Areas: Incidental use areas are small areas with a different use than the overall occupancy (see Section 2.2.1 for further details). Such areas usually need to be enclosed by fire barriers.

Means of Egress Components: Fire barriers are also used to protect

means of egress in case of fire. Means of egress are described in detail in the later part of this chapter, along with the fire-resistance considerations applicable to its different components such as stairwells, exit passageways, horizontal exits, exit doors, corridors, etc.

Vestibules: Vestibules adjacent to a smokeproof stairwell or elevator hoistway that is located between the shaft and the exterior exit door should also be smokeproof. See Figure 3.1.3.1 C for an illustration of the various specifications in this case. The codes specify the number and locations of ducts, and the amount of supply and exhaust air.

39

Note : Different occupancies within a single building should be separated through a fire barrier. See Section 2.2 of this thesis for further details. Occupancy separation is required between two storeys, but tenant separation is not. That is, while the walls between tenant spaces on a single floor may need fireresistance rating, the rating of the floor between two tenants on different storeys is determined only using the construction type of the building.

Opening protectives prevent the spread of fire and smoke through an opening in a rated wall. These are usually used for doors and windows, and therefore are special cases of through-penetration protectives that also consider penetrations for wiring, ducts, pipes, etc. According to NBC[4], in case of openings in an external wall, the area of the opening should not exceed 75% of the area of the wall, and should be protected with fire resisting assemblies or enclosures (see Figure 3.1.3.2 A). It also requires that the assembly or enclosure should have at least as much fire rating as the wall or floor in which these are situated, and they should also act as smoke barriers to allow safe evacuation of occupants. Finally, openings should provide a clear height of 2100 mm for passage of occupants.[5] Next, the most common opening protectives are described.

Rated Door Assemblies: A door assembly typically consists of the door,

the frame, and the door hardware. The doorway (i.e. the wall opening) is also typically considered part of the door assemblyâ&#x20AC;&#x201D;including the lintel above and the threshold below. Unlike wall, floor, and ceiling assemblies that are assigned a fire-resistance rating, door assemblies are assigned a fire-protection rating, based on the rating of the incorporating wall. This is because door assemblies do not only need to help control the spread of fire, but also need to allow easy evacuation of the occupants. â&#x20AC;˘ Doors and Frames. They usually have less stringent specifications than the incorporating wall because they only make up a small portion of the entire wall, and are not generally exposed to the same level of fire as walls. While earlier doors with fire-protection were typically flush and either solid core wood or hollow metal, today use of glazing has allowed more options in configurations and finishes of rated doors. Fire-rated frames can be made of wood, steel (i.e. hollow metal), or aluminum depending on the rating required. The most commonly specified rated frame is hollow metal.

Fire Protection and Life Safety > Fire Protection Systems > Passive Systems

3.1.3.2 Opening Protectives


40

Right : Figure 3.1.3.1 C Shows a vestibule near a stairwell with a smoke-proof enclosure. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.153.

Ventilation system for a smoke-proof enclosure should be independent of other ventilation systems in the building, and should have standby power.

Vestibule should be separated from the smoke-proof enclosure by a 2-hour fire barrier.

Door should be fire rated, and should have self-closing devices and a drop sill to minimize air leakage. Vestibules should be 72” (1829 mm) long in the direction of egress and 44” (1128 mm) wide. Vestibules should have arrangement for ventilation, possibly an opening in the exterior wall or mechanical ventilation with vents opening to outside air.

Right : Figure 3.1.3.2 A

Chapter 3 : Building Services

Shows openings in fire walls and glazing in fire doors. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.108.

Fire-resistance rated glazing in a fire door. This should not be larger than 5 m2.

Total area of all openings should be at most 75% of the area of a fire-rated wall.


• Door Hardware. Door hardware plays a key role in safe and quick evacuation of the occupants. Door hardware includes hinges, latches and locksets, pulls, and closers. The specifications are most stringent for hinges, latch sets, and closing devices because they should hold the door in spite of pressure and heat during fire. For example, fire-rated hinges should be made of steel or stainless steel. Fire-rated exit doors also require specific types of latch or pull known as fire exit hardware or panic hardware.[6] Typically pressing a panel or bar would release the door latch and open the door, while closing the door would be automatic. Closers may be surface mounted or concealed within the door, frame, or floor. If it is desirable that certain rated doors be open all the time, an electromagnetic or pneumatic hold-open device can be used, which hold the door open until an emergency occurs. The designer should also refer to accessibility standards when deciding the location of door hardware on the doors.

41

Fire Window Assemblies: Windows can either be a separate entity or

part of a door assembly (e.g., transom, sidelight, or vision panel). A fire window typically consists of a frame, glazing material, and hardware. Fire windows are commonly used as openings in corridor walls, room partitions, and smoke barriers. Fire windows have a fire-protection (rather than resistance) rating similarly to fire doors. This rating depends on the location of the window within the building. When used as a non-fire-rated smoke partition, the window should be sealed to prevent the passage of smoke.

size, thickness, location, and types of glazing materials that can be used in opening protectives such as fire doors and fire windows. Glazing materials are rated by their ability to stay in place in the event of fire, resistance to thermal shock in a hose stream test, strength against human contact, and resistance to heat transfer to the unexposed side. Based on strength against human contact, they are classified into Categories I and II. Category I glazing resists the equivalent impact of a small child, whereas Category II glazing withstands the equivalent impact of a full-grown adult. NBC[7] allows only two types of glazing in construction types I, II, and III—wired glass and electro-copper glazing. In construction type IV, hardwood sashes and frames are also allowed. The area of wired glass or electro-copper glazing should be at most 5 m2 (see Figure 3.1.3.2 A). Below, various types of glazing are described; see Figure 3.1.3.2 B for an illustration.

• Wired Glass. This consists of steel wire mesh sandwiched between two layers of glass, which help distribute heat and increase the strength. This should have at least half hour fire resistance, and falls in Category I impact-resistance. Hence, it should not be used in high traffic locations. It sashes and frames should be made of iron, stainless steel, or other suitable metal, securely bolted or keyed into the wall, except in the case of panels in internal doors. Glass panels should be set in recess or at least 6 mm wide/deep grooves, with due allowance for expansion. These should also be secured by hard metal fastenings to the sashes or frames independently of any cement or putty used for weather-proofing purposes. • Electro-copper glazing. This should also have at least half hour fire resistance rating. Its sashes and frames have the same specifications as

Fire Protection and Life Safety > Fire Protection Systems > Passive Systems

Rated Glazing and Frames: The codes state certain specifications for the


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those of wired glass. Its sectional lights should also be set in a recess or groove similarly to the glass panel, but the minimum width/depth of the recess/groove should be 6.5 mm. Examples of other glazing used are as follows. • Specially Tempered Glass. Glass should be specially tempered to be able to achieve a 20 minute fire rating. It has Category II impact-resistance. However, it does not pass the hose stream test. Hence, it should not be used near sprinklers. • Glass Block. Typically this has up to 45-minute of fire rating, and can be used in 1 hour rated wall. However, the codes may require them to be installed in steel channels, and to be of limited area. • Clear Ceramics. Clear ceramics—also known as transparent ceramics—have high heat and thermal shock resistance, and hence can be rated from 20 minutes to 3 hours. They also have high impact-resistance (Category II). Hence, they are used in areas such as lobbies and offices where the aesthetics and safety are key. • Insulated and Multilayer Laminated Glass. These can have various materials sandwiched between two layers of glass laminated together. Usually rated between 60 to 90 minutes, they can be used in 2 hour rated wall. • Transparent Wall Units. While laminated glass is used in smaller windows, transparent wall units can be used in larger openings. In fact, they are tested as walls rather than glazing within wall units, and therefore are needed to be self-supporting. They are formed by a combination of different materials (including glazing products). They are transparent, have high impact-resistance, and have up to 2 hour rating; for the latter, they use an inert material that turns into foam during a fire. Uniquely, they do not allow transfer of heat, which makes them a “full glass” barrier wall, e.g., to be used in stairwells.

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Right : Figure 3.1.3.2 B Shows various types of fire rated glazing used. CREDIT: (a) http://www.inspiritoo.com/glasswire.html (b) www.doityourself.com/stry/ how-to-cut-tempered-glass (c) http://batlanbuildingmaterials. com/glass-blocks/ (d) http://noida.all.biz/ clear-glass-g559460 (e) http://www.hjbl168.com/en/ index.asp

(a) Wired Glass

(b) Specially Tempered Glass

(d) Clear Ceramics

(e) Laminated Glass

(c) Glass Blocks


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Frames: All glazing materials should be fixed within a rated frame (typically a hollow steel frame). The rating of the frame typically matches the rating of the glazing. Rated frames are also used around the windows within fire-rated doors. Frames may have up to 2 hours of fire rating, and may be resistant to transfer of heat. Larger sheets of glass may be used in frames because of their higher ratings. However, the size may be restricted by the codes. Skylights: Wired glass for skylights or monitor lights should also have at least half hour fire resistance rating. Its frame should be continuous and divided by iron (or other hard metal) bars spaced at most 700 mm apart. The frame should be supported on a curb of metal or wood covered with sheet metal. The toughened glass should independently be secured by hard metal fastenings to the frame and bars. Louvers: These should have at least half hour fire resistant. Glass facade: These should be at least one hour fire resistant.

A through-penetration is an opening that pierces the entire thickness of a wall, floor, or ceiling assembly. When the assembly itself is fire rated, the penetrations should be protected with rated assemblies such as firestops, draftstops, fireblocking, and fire dampers. Through-penetration protection systems also need fire protection rather than resistance, because they are also important for occupant evacuation. Common through-penetration protectives are described below.

Firestops: Firestops are used to seal openings created by plumbing pipes, electrical conduit and wire, HVAC ducts, communication cables, etc. so that smoke, fire, and sometimes even heat do not pass. Firestops are also used at intersection of walls/ceilings and at seams in gypsum board in rated walls. See Figure 3.1.3.3 B.

Note : Membrane penetrations are similar to through-penetrations but only penetrate one side of the assembly, e.g., an electrical outlet or a sprinkler head. See Figure 3.1.3.3 A for an illustration. These should also be protected, and therefore, sometimes a small filling area around the penetration is required.

Firestops can be F-rated (weaker) or T-rated (stronger). F-rating is given based on the number of hours of flame and hot gas resistance, hose stream performance, and the ability to stay in the opening. The stricter T-rating requires F-rating criteria and a maximum temperature riser. Firestops are made of noncombustible materials such as fire-rated caulk, silicone foam, mortar, mineral wool, fire-resistive board, wire mesh, collars, and clamp bands.

Through penetration: Pierces the entire thickness. Membrane penetration: Pierces only one side.

Left : Figure 3.1.3.3 A Shows the difference between through and membrane penetrations. Adapted from Ching, F. D. K., and Winkel, S. R. â&#x20AC;&#x153;Building Codes Illustrated: A Guide to Understanding the 2012 International Building Codeâ&#x20AC;? Wiley Publishing, 2012, p.108.

Fire Protection and Life Safety > Fire Protection Systems > Passive Systems

3.1.3.3 Through-Penetration Protectives


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Firestop

As per NBC[8], this is defined as a fire resistant material or construction installed at joints or in concealed spaces to prevent the spread of fire and smoke. It should have a fire rating not less than that of its adjoining assemblies.

Firestop devices are factory-built and installed as a part of the penetration (see, e.g., sleeve within the wall/floor assembly for penetration by a pipe in Figure 3.1.3.3 B), whereas firestop systems are built on-site and applied after through-penetration is installed. T-rated firestop devices can be endothermic or intumescent. Endothermic firestops release water when exposed to heat, which causes a cooling effect. An intumescent firestop expands in volume under fire conditions, forming a strong char and sealing any gap to stop any penetrations.

Right : Figure 3.1.3.3 B Shows firestop, various methods of applying it, and its various uses. CREDIT: (a) http://baggout.com/product/ Fire-Stop/52744 (b) http://www.stifirestop.com/ products/product-selector/lc/ (c) http://www.fireretardantsinc. com/unique_fire_stop/sleeve_system.htm (d) https://www.hilti.ca/firestop (e) http://www.easterninsulation. com/firestopping.html

Fireblocks and Draftstops: Fireblocks (or fireblocking) and draftstops are

used for restricting the spread of smoke and fire through concealed spaces. See Figure 3.1.3.3 C. In interior projects, they are used in several conditions such as: •

Dropped or coved ceilings. When a wall stops at the underside edge of a dropped or coved ceiling.

Double stud walls. When a deeper wall assembly is required to accommodate large pipes and mechanical ducts or for acoustical separation. Long walls require fireblocking at certain intervals.

Stairs. At the top and bottom of stairs to block the open space between the steps and the ceiling below.

Concealed floor spaces. At certain intervals when hardwood floors or other finishes are installed on furring strips (i.e., sleepers).

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Right : Figure 3.1.3.3 C Shows fireblocks and draftstops. CREDIT: (a) http://www.astroflame.com/firestop-block.html (b) http://derechopedia.com/ under-door-draft-stopper-lowes/

(a) Fireblock

(b) Draftstop: used under the door to fill the air gap and prevent passage of smoke.


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Draftstops are used for large concealed spaces such as certain floor/ceiling spaces, attics, and concealed roof spaces in Residential uses. These are typically required in combustible construction types, but not if building has an automatic sprinkler system. Draftstops are usually made of noncombustible materials such as gypsum board and certain sheathing and plywood materials. It is important that the material is supported so that it stays in place during an initial fire.

Damper Systems: A damper is another type of opening protective that au-

tomatically interrupt the flow of air during an emergency so that it restricts the passage of smoke, fire, and heat. It is used in HVAC systems, either when a duct passes through a rated assembly or an air transfer opening is cut into a rated assembly. This may need to be specified by a mechanical engineer. There are two kinds of damper systems: static dampers that can only be used in static HVAC systems, and dynamic dampers that can be used in both static and dynamic HVAC systems. There are three types of dampers: fire dampers, smoke dampers, and ceiling dampers. Sometimes, combinations of these dampers may also be used. Dampers may sometimes also be used for controlling the volume of air for the heating and cooling system during normal use.

Shows fire dampers and how they work. When fire occures and is passing through the duct, a fusible link melts and drops the accordian flolded door to block fire. CREDIT: http://iakki.com/user/core/home/ detail.php?ID=16

Accordian folded fire damper in open (left) and close (right) conditions.

Fire Protection and Life Safety > Fire Protection Systems > Passive Systems

Left : Figure 3.1.3.3 D


46 Note : Today, programmable detection systems have allowed coordinating many smoke and fire detectors and waiting for multiple signals such as smoke, heat, molecular gases, aerosols, heat conduction, acoustic waves, etc. before declaring fire. This has helped reduce the number of false alarms significantly.

â&#x20AC;˘ Fire Dampers. Fire dampers are typically required in ducts or air transfer openings in rated wall assemblies. Usually placed inside the duct or outside as a collar fastened to the wall or ceiling, they have a fusible link that melts when it reaches a certain temperature. This closes the damper and seals the duct. They can have up to 3 hours of rating. The required rating depends on the rating of the incorporating assembly. See Figures 3.1.3.3 D and 3.1.3.3 E.

Right : Figure 3.1.3.3 E

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Illustrates that fire dampers should be put in ducts that connect multiple storeys to control the spread of fire. CREDIT: http://publicecodes.cyberregs. com/icod/ibc/2009f2cc/icod_ ibc_2009f2cc_7_sec016.htm

â&#x20AC;˘ Smoke Dampers. Smoke dampers are similar to fire dampers, but activated specifically by smoke (using a smoke detector inside the duct) rather than heat. They are less common than fire dampers, and are used typically in smoke barriers. A smoke damper may be installed as part of a larger smoke evacuation system. Smoke dampers are categorized into four classes: Class I, Class II, Class III, and Class IV. The requirements drop from Class I to Class IV.


• Ceiling Dampers. Ceiling dampers—also known as ceiling radiation dampers—are used in suspended ceilings that are part of a rated assembly. They can be located inside the duct or in the air diffuser that supplies air. The function of the ceiling dampers is to prevent heat from entering the space between the ceiling and the floor or roof above. Additionally, they also stop passage of heat through the duct system. Ceiling dampers are activated by heated air passing through the damper. See Figure 3.1.3.3 F.

47 Below : Figure 3.1.3.3 F Shows the use of ceiling dampers. CREDIT: http://publicecodes.cyberregs. com/icod/ibc/2009f2cc/icod_ ibc_2009f2cc_7_sec016.htm

NBC[9] provides specifications for fire protection in air-conditioners and ventilation systems (also, see good practices [4(10)] through [4(13)]). This is because such systems can increase fire and aid passage of smoke, which can significantly increase the associated risks. •

Ventilation systems that connect more than one floor or fire areas should be provided with dampers that automatically close in case of fire.

All fans except those designed to remove smoke from the fire should stop automatically.

Air-conditioning systems in assembly places with occupant load more than 1000 or in large departmental stores or hotels with more than 100 rooms in a single block should have effective smoke control means and smoke detecting devices.

Separate air handling units should be provided for every floor (rather than a common air-conditioning duct) to minimize the danger of spread of fire and smoke through such ducts.

NBC also requires that automatic smoke venting facilities should be installed in windowless buildings, underground structures, large area factories, hotels and assembly buildings (including cinema halls). These systems should additionally have manual controls too.

Natural draft smoke venting should utilize roof vents or vents near the ceiling level. If such vents are closed, they should open automatically in case of fire.

If smoke venting facilities are used for safe exit, they should prevent dangerous accumulation of smoke for a sufficiently long time for the occupants to evacuate.

Smoke exhaust equipment should have a minimum capacity of 12 air changes per hour.

Mechanical venting, if employed, should be fire rated.

The apertures of smoke vents should be readily accessible for opening by fire service personnel.

Additional precautions apply to installation of chimneys and heating apparatus.

Fire Protection and Life Safety > Fire Protection Systems > Passive Systems

AIR-CONDITIONING AND VENTILATION REQUIREMENTS


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3.1.4 ACTIVE SYSTEMS While passive fire protection systems focused on compartmentation and use of rated assemblies to control spread of smoke and fire, active fire protection systems detect fire, alarm the occupants, and then attempt to extinguish the fire. Accordingly, there are three subsystems in an active fire protection system, which are described next in the chapter: detection system, alarm system, and extinguishing system.

3.1.4.1 Detection Systems The goal of fire detection systems is to know that there is a fire as early as possible, because fire is easy to extinguish in its early stages, and this allows the occupants more time to evacuate the building. Hence, detection systems, also known as initiating devices, are designed to detect early signs of fire. It is important that the system should be able to detect any anticipated type of fire. For example, smoldering fires generate very little heat but a lot of smoke, and liquid fires actually cause a drop in the temperature; these fires should also be detected. CARBON MONOXIDE DETECTION Carbon monoxide is produced when organic material has incomplete combustion. Exposure to carbon monoxide develops flu-like symptoms, later causing drowsiness / unconsciousness, and ultimately death. Sources of carbon monoxide include widely used appliances or engines powered by gas, such as automobiles, lawnmowers, stoves, and hot water heaters. However, building codes regarding carbon monoxide are still in their infancy. A few detectors are available for public use, which may be used to ensure safety.

Three major types of detection systems are smoke detectors, heat detectors, and manual alarms (see Figure 3.1.4.1). While smoke detectors are most common, heat detectors may be needed additionally in some cases. Below, various alarm systems are described in detail. An interior designer should work with an electrical engineer or a fire protection designer to coordinate these systems. These should also be connected to backup power supply for emergency situations.

Smoke Detectors: Smoke detectors are very important in the case of fire

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because smoke and toxic gases are the primary dangers to occupant lives. Further, certain fires (e.g., smoldering fires) do not produce much heat. Hence, smoke detectors are required to detect such fires. They are often used with smoke dampers. Apart from this, in some cases smoke detectors provide another functionality of automatically closing doors or activating automatic doors. This provides greater compartmentation. Smoke detectors can either be wired independently or to act as a group (single-station vs. multi-station). Correspondingly, they can detect fire in a single location or in an entire area. Codes usually specify whether smoke detectors are required or not, but choosing their location is left to the interior designer. This is a critical choice: For example, putting smoke detectors in the kitchen would generate many false alarms, whereas putting them near intersection of walls where the smoke might bypass the detector due to air currents may not generate alarms when required. Smoke detectors should typically be placed on walls, 6 to 12 inches (152 to 305 mm) from the ceiling.[10]


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Heat Detectors: Next to smoke, heat is the most common signal for detecting fire. Heat detectors are especially required when liquid fires (that cause a drop in the temperature) are anticipated. Heat detectors should be used together with smoke detectors to avoid false alarms. Manual Fire Alarms: Manual fire alarms are required only in cases when

an automatic smoke detection system or a sprinkler system is missing. However, manual fire alarms are almost always provided. While the alarm usually does not activate fire extinguishing system, it notifies the occupants of the fire. Manual fire alarms should be located near every exit door, typically less than 5 feet (1525 mm) from the door.[10] The codes usually specify their color, signage, and power supply details. Since these alarms are to be used by humans, accessibility standards should also be considered.

Note : Another type of alarm system is accessible warning system that notifies the occupants using means other than audio or visual means, such as vibrating sensation.

Left : Figure 3.1.4.1

(b) Heat Detector

(c) Manual Fire alarm

(d) Manual Fire alarm

3.1.4.2 Alarm Systems The purpose of alarm systems is to make the occupants aware of an emergency so that they can evacuate. Alarm systems, also known as notification appliances, can also be used to notify emergencies other than a fire, e.g., toxic spills or severe weather conditions. Alarm systems can be activated manually (manual alarms) or automatically (smoke and heat detectors). Similarly to detection systems, alarm systems could be single-stationed, i.e. they only notify occupants in one area, or multi-stationed, i.e. they notify occupants throughout the building. The alarm system can also notify a central control room which can then take appropriate further action. Often, an alarm system would notify the local fire departments as well.

Note : Today, alarm systems integrate with mechanical system to stop air distribution that would spread smoke, and with security system to automatically open doors in case of fire that would otherwise be closed for security.

Fire Protection and Life Safety > Fire Protection Systems > Active Systems

(a) Smoke Detector

Shows smoke detector, heat detector, and manual fire alarm. CREDIT: (a) http://www.coronafiresafetyfoundation.org/ (b) http://www.vpaluf.szm.com/ eps.htm (c) http://www.firexequipment.com/ in-case-of-fire.html (d) http://www.securitysystemspune.com/fire-alarm-system.html


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Like detection systems, alarm systems should also be connected to a backup power supply. The interior designer should work with an electrical engineer to make sure that the alarm system is set up properly. The interior designer should coordinate the location of various alarms so that all occupants in the required area can be notified. Below, various types of alarms are described.

Visual and Audible Alarm Systems: To maximize the number of occupants notified, alarms mainly communicate to the occupants through audible and visual signals. Audible alarm is a loud sound (typically a steady horn-like sound, a pattern of sounds, or bell sounds). The intensity should be more than the usual level of noise in the space. Thus, an alarm in a factory would be louder than an alarm in an office building. Alarms should be placed. Visual alarms originated from accessibility standards. They typically involve a pulsing light strong enough to awaken sleeping occupants as well. In case of multiple types of emergencies, different patterns or intensities should be used. Alarms should be placed along the natural path of escape and at each exit so that the occupants can locate the exit through sound. When a single device is used with both audible and visual signals, it should be located according to the specifications of visual alarms. Further, accessibility standards should be considered when determining the location of the alarms.

Voice Communication Systems: Also referred to as audio systems, voice

communication systems are essentially intercoms through which the occupants can be notified of emergencies. Such systems can also provide the location of the emergency and directions for egress. Such systems are typically required in high-rise buildings, assembly and hazardous occupancies, large storage facilities, and factories.

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Note : As per NBC[11], if an area is fire protected but surrounded by other unprotected areas or buildings, then due to exposure hazard, either the walls of the protected area that face the unprotected areas/ buildings should be made of fire resistant material or such walls should be provided with water curtain that can be actuated in case of emergency.

3.1.4.3 Extinguishing Systems The purpose of extinguishing systems is to control and extinguish fire once it occurs. They are also known as suppression systems. Installation of such systems should be coordinated with electrical and mechanical engineers as well as fire protection designers. Various types of fire extinguishing or fire fighting systems can be used. Some examples are fire extinguishers, hose reels, wet and dry risers, down-comers, yard hydrants, automatic sprinkler systems, etc. See Figure 3.1.4.3 A. See Table 23 in Part 4 of NBC[12] for a detailed description of the fire fighting installations required in each occupancy type and its subtype, and see Table 24[13] for specifications regarding the size of risers. Below, three most common extinguishing systems are explained.

Fire Extinguishers: Portable fire extinguishers are meant for the occu-

pants to manually extinguish fire. Since they are movable and do not require plumbing lines, they are often part of interior projects. Fire extinguishers can either be surface mounted (while protruding at most 4 inches/100 mm into a path of travel) or be recessed within a wall. In any case, the extinguisher should be tested and should be clearly visible (or its container should be clearly marked). Most occupancies require fire extinguishers. Common places where extinguishers should be put are near commercial cooking equipment, in areas with flammable liquids, in buildings under construction, near open flames, in laboratories and computer rooms, etc. IBC[10] classifies buildings as Class


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A, B, or C hazardous, where Class A is the least hazardous and the most common. It also restricts the maximum travel distance of any occupant to the nearest fire extinguisher. For example, in Class A building, no occupant should be more than 75 feet (23 m) away from a fire extinguisher. Accessibility standards should be referred when deciding the weight and the height of the fire extinguisher as well as where it should be mounted.

Standpipes and Fire Hoses: These are manual, fixed fire suppression systems where a folded fire hose is attached to a common water pipe running underneath. The hose is usually displayed in a glass cabinet. Because they need to be connected to the water pipes, they are usually installed during the initial construction of the building. Hence, often these are not part of interior projects.

Left : Figure 3.1.4.3 A Shows three types of fire extinguishing systemsâ&#x20AC;&#x201D;(from left to right) fire extinguishers, standpipes, and fire hoses. CREDIT: (a) http://www.911fireextinguishers. com/ (b) http://safety108.blogspot. in/2011/09/ch7-fire-hydrant-system. html (c) http://www.fireprotectionproducts.co.uk/fire-hose-reels

(b) Standpipe

(c) Fire Hose

Sprinkler Systems: Introduction of automatic sprinkler systems has been a

breakthrough in increasing life safety. As a result, more and more occupancies are now required to have an automatic sprinkler system. Major factors determining the need for a sprinkler system are the size of the space, the number of occupants, the mobility of the occupants, height and area of the overall building, types of hazards present, and sometimes even the capacity of the local fire department. Certain situations require additional sprinkler locations. For example, use of a continuous glass wall as a rated wall may require sprinklers on both ends. Similarly, use of light-transmitting plastics may also require additional sprinkler heads. Installation of automatic sprinkler system allows relaxation of other specifications. An automatic sprinkler system typically releases water when activated by heat. The water may cause some damage, but this is substantially less than the damage caused if the fire department needs to extinguish the fire using a fire hose. Below, various types of sprinkler systems and types of sprinkler heads are explained. Types of sprinkler systems: There are four major types of sprinkler systems used. See Figure 3.1.4.3 B.

Automatic Sprinkler System This is defined as a system of water pipes fitted with sprinkler heads at suitable intervals and heights and designed to actuate automatically, control and extinguish a fire by the discharge of water.

Fire Protection and Life Safety > Fire Protection Systems > Active Systems

(a) Fire Extinguisher


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1. Wet pipe system. In this, sprinkler head is connected to a pipe that is always filled with water. Heat activates the system by melting the fuse link, which immediately releases water. This is most common type of system. 2. Dry pipe system. In unheated places (e.g., a storage facility), pipes filled with compressed air/nitrogen are used instead of water-filled pipes to prevent freezing. When the system is activated, first the air is released and then water floods the pipe to extinguish the fire. 3. Deluge system. This is an open-head water system which is usually activated by a separate detection system. This type of system is used when large quantities of water need to be discharged. 4. Preaction system. This is also activated by a separate detection system. This system has a delayed response to activation, which is useful if the sprinkler needs to be manually turned off after activation because they are not deemed necessary. This is commonly used in places like museums where water damage could be substantial.

Right : Figure 3.1.4.3 B Shows various types of sprinkler systems. CREDIT: (a) http://www.greenmtnsprinkler. com/index.html (b) http://www.metrofire.com/ (c) http://www.indiamart.com/zapfire-gurgaon/fire-safety-products. html (d) http://www.baconfire.com/ Foam-Fire-Protection.html (a) Wet / Dry pipe sprinkler system installation

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(b) Wet sprinkeler with water

(c) Dry sprinkeler with gas

(d) Deluge system with water/ foam

Types of sprinkler heads: Sprinkler heads are classified according to how quickly they respond to a fire, the size of the orifice, the distribution of water, etc. Another important consideration is the orientation of the head, which can be pendant, upright, sidewall, recessed, or concealed, as shown in Figure 3.1.4.3 C.


Left : Figure 3.1.4.3 C

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Shows various types of sprinkler heads. CREDIT: http://www.firefightsystems.com/ sprinkler-head.htm

2. Fast-response sprinkler head. These are not really fast but rather early response systems that are activated by a low level of heat. The response time depends on ceiling height, spacing, ambient room temperature, etc. 3. Residential sprinkler head. These are used not to extinguish fire but rather minimize heat and carbon monoxide production so that occupants have more time to evacuate the building. They have a quick response and unique spray pattern. These are often recessed and in pendant or sidewall orientation. 4. Quick-response sprinkler head. These are used in residential or commercial types, and can be in upright, pendant, or sidewall orientation. 5. Extended coverage sprinkler head. These type of heads cover up to 400 sq. ft. (37.2 sq. mt.). These are used in open large areas due to their higher water pressure and flow rate. These can be in upright, pendant, or sidewall orientation. 6. Large drop sprinkler head. These deliver water in large droplets, and therefore are used in storage facilities where fires may be hard to suppress. 7. Open sprinkler head. These heads are always open and thus activated by a separate detection system. They can release large quantities of water, and are therefore used in places where severe fires may occur. 8. Specialty sprinkler head. Sprinkler heads can be made for special needs such as tamper-resistance or corrosion-resistance. However, these are mainly used for aesthetic reasons.

Fire Protection and Life Safety > Fire Protection Systems > Active Systems

1. Standard spray head. These are most common type of heads. These can be used in upright, pendant, sidewall, or concealed orientations. Pendant or sidewall types may be recessed. Typically, 225 sq. ft. (20.9 sq. m) area is covered when water flows from these heads.


54 Note : All floors in a high-rise buildings are required to be sprinklered because otherwise a fire can start from a lower unsprinklered floor, collect more and more fire load while moving upwards, gather momentum, and reach a sprinklered floor as a fully developed fire. In this case, the sprinklers on that floor would be ineffective.

Note : False ceiling should not be used for storage purposes or as return air plenums.

Where sprinklers are usually required? The use of automatic sprinkler system is necessary in the following situations.[14] 1. Basements used as car parks or storage occupancy, if larger than 200 m2. 2. Any room or compartment of a building larger than 1125 m2. 3. Departmental stores or shops, if the aggregate covered area exceeds 500 m2. 4. All non-domestic floors of mixed occupancy not having independent staircases and which constitute a hazard. 5. All floors of all high-rise buildings. 6. Dressing room, scenery docks, stages and stage basements of theatres. 7. False ceiling voids exceeding 800 mm in height. 8. Canteen provided in upper floors of assembly occupancy subtypes D-1 and D-2. Considerations in sprinkler design: The major decisions that an interior designer has to make regarding sprinklers is the type of sprinkler system, and the type and layout of sprinkler head. Many parameters affect these decisions. For example, configuration of the space and the desired coverage affect the layout of sprinkler heads. Ceiling height and the type of ceiling (sloped, horizontal, smooth, or coffered and exposed ceiling versus finish ceiling) affect the layout, the sprinkler head type, and the sprinkler head orientation. It is important to make sprinkler-related decisions relatively early in the project because the choice of sprinkler system affects many other code specifications. It should also be noted that changes to an existing space can also affect sprinkler specifications.

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Sprinklers are not the appropriate choice for extinguishing fire near large electrical equipment or in restaurant kitchens and other rooms which have a potential of grease fire because the use of water is dangerous in such situations. There are non-water-based sprinkler systems which use wet or dry chemicals, carbon dioxide, and clean-agent extinguishing chemicals.


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End Notes 1. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 13. 2. Ibid. Part 4, pp. 65-71, 77-82. 3. Barnett, C., Sfintesco, D., Scawthorn, C., and Zicherman, J.B. Fire safety in tall buildings. Council on Tall Buildings and Urban Habitat. Committee 8A. McGraw-Hill, 1992. 4. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 23. 5. Ibid. 6. What is panic hardware? (Question: Code Corner). Door and Hardware Institute, Highbeam Research, 2003. Accessed 26 May 2014 <http://www.highbeam.com/doc/1G1-105913556.html>. 7. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 25. 8. Ibid. Part 4, p. 8. 9. Ibid. Part 4, p. 24. 10. The International Building Code. International Code Council, 2012. 11. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 46. 12. Ibid. Part 4, pp. 25-43. 13. Ibid. Part 4, p. 48. 14. Ibid. Part 4, p. 46.


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3.2 Means of Egress

In This Part, 3.2.1 Parts of an Egress Path 3.2.2 Exit Accesses 3.2.2.1 Corridors

3.2.2.2 3.2.2.3 3.2.2.4 3.2.2.5

3.2.3 Exits 3.2.3.1

Doors and Doorways Staircases Ramps Aisles and Aisle Accessways

Number of Exits 3.2.3.2 Arrangement of Exits 3.2.3.3 Exit Width 3.2.3.4 Types of Exits

3.2.4 Exit Discharges 3.2.5 Egress Signage and Illumination 3.2.5.1 Egress Signage

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3.2.5.2 Emergency and Escape Lighting

The importance of means of egress for life safety can never be overstated. Means of egress facilitate evacuation of the occupants in case of emergencies such as fire evacuation, moving an injured persion, evacuation due to internal riots or disturbances, etc. On a typical means of egress path, the occupant starts through an exit access, which leads to an exit, which further leads the occupant to the exterior of the building (or in some cases to a safe area within the building). Sometimes the occupant may be required to use an exit discharge to go from the exterior of the building to the nearest public street outside the building perimeter. This section covers each part of the path in detail. Further, to aid the occupants in their egress, two mechanisms are deployed: egress signage and egress path marking. Egress signage mostly consists of â&#x20AC;&#x153;EXITâ&#x20AC;? signs, but may include other signs to lead the occupants in the right direction. Egress path marking uses emergency lighting to illuminate egress path for the ease of the occupants. These are covered at the end of the section.


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3.2.1 Parts of AN Egress Path Means of egress are usually divided into three main categories: exit access, exits, and exit discharge. Note that all three parts should be free of obstructions for better evacuation.[1] Exit access: The portion of a means of egress that leads to the entrance of an exit. This includes all rooms and spaces from where the occupants begin to egress, and also includes any doorways, aisles, corridors, stairs, or ramps they use on the way to an exit. Exit: The portion of a means of egress that is protected, fully enclosed, and between the exit access and the exit discharge or public way. This can simply be an exterior exit door or it can have enclosed stairways and ramps. In special cases, certain corridors or passageways may also be part of an exit. The components of an exit usually have higher fire rating requirements than those of an exit access. Exit discharge: The portion of a means of egress between the termination of an exit and the public way. This can be inside a building such as the main lobby, foyer, etc. or outside a building such as an egress court, courtyard, or patio. Left : Figure 3.2.1 A

Shows three components of a means of egress: exit access, exit, and exit discharge. Adapted from Dave, W. A. â&#x20AC;&#x153;[IBC2006] Ch.10 Means of Egressâ&#x20AC;?. Study Blue. 4 March 2014. <http://www. st u d y b l u e . co m / n o te s / n o te / n / ibc2006-ch-10-means-of-egress/ deck/4380781 >.

Exit Access

Exit Discharge

Figure 3.2.1 A and 3.2.1 B illustrate various components of a means of egress. While in most cases the final destination is a public way in the exterior of the building, in some cases a safe area of refuge within the interior of a building can also be the destination.

Means of Egress > Parts of an Egress Path

Exit


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Public way: The area outside a building between the exit discharge and a public street, for example, an alley or a sidewalk. This is usually marked by a clear width and height from the adjoining public street. Refuge Area: A space or area providing protection from fire and/or smoke where occupants who are unable to use other means of exit can stay temporarily to await further instructions. Each of the three parts of means of egress are described next. 118

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Right : Figure 3.2.1 B Illustrates each part of an egress path and its various components in a typical building. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.118.

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Figure 4.2 Means of Egress in a Typical Building

3.2.2 Exit Accesses Note : NBC[2] does not allow an exit access passing through another occupied space, e.g., an adjoining or an intervening room.

An exit access is the part of an egress path which leads to an exit. It can include doorways, corridors, staircases, ramps, aisles, etc. Exit accesses do not necessarily need to be enclosed and do not necessarily require a fire-resistance rating, but it should be adequately ventilated. This section describes various types of exit accesses and the kind of specifications applicable to such accesses that are critical to life safety in emergency situations.


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3.2.2.1 Corridors An exit access corridor is a corridor that leads to an exit. Typically it is not required to be fire-rated, but may be required if it serves an entire floor, especially in nonsprinklered buildings. Its walls are considered fire partitions. Hence, the ratings of the adjoining floor or ceiling assemblies are determined using only the construction type of the building. The codes state two kinds of specifications for corridors: 1. A minimum width to ensure adequate space for people to get to the exit, which is determined using the occupancy classification and the occupant load (see Figure 3.2.2.1 B). 2. A maximum length to ensure that the time required to reach the exit is reasonable. Additionally, accessibility standards should also be considered, which require sufficient space for change in direction as well as for passing two wheelchairs, and also if any objects are protruding into the corridor. Figure 3.2.2.1 A illustrates these specifications.

Left : Figure 3.2.2.1 A

Specifications in NBC[3]: • The width of an exit corridor should be at least as much as the width of the exit doorway. • If the corridor is used as means of discharge at the end of a stairway, then the height of the corridor should be at least 2.4 m.

Note : Escalators and moving walks are not considered as parts of means of egress. However, they may be provided as additional paths of travel.

Means of Egress > Exit Accesses

Illustrates various specifications regarding exit access corridors. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.133.


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Right : Figure 3.2.2.1 B Illustrates that the required egress width (along with the occupant load) is added when two corridors merge.

DEAD-END CORRIDOR A dead-end corridor is a corridor with only one direction of exit. So if a person enters a dead-end corridor, the only way out is to retrace the path. Since such corridors may create panic during emergency, many codes (including NBC[4]) restrict the distance of the dead end of a corridor from the nearest exit, or even the length of a dead-end corridor. In some codes (e.g., see IBC[5]), an automatic sprinkler system allows longer dead-end corridors.

3.2.2.2 Doors and Doorways A doorway is the opening in the wall in which a door is placed. The considerations given below illustrate why doors and doorways are crucial in case of an emergency, and emphasize that they should be designed with special care. Swing Direction: Exit doors should generally open in an outward fashion, along the direction of exit. The only exception is doors of individual rooms which may open inwards in a corridor to avoid reducing the width of the corridor and to permit smooth flow of traffic in the corridor. In this case, if opening inwards is not possible, other options such as using a 180-degree swing door (see Figure 3.2.2.2 A given below) , placing the door in an alcove, enlarging its landing, or using sliding doors may be allowed in some cases.

Right : Figure 3.2.2.2 A

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Shows the use of 180-degree swing door and the corresponding specifications.

The door should project a maximum of 7â&#x20AC;? (178 mm) into the required width when fully opened against the wall of the passage. The opening of the door should not reduce the required width by more than one-half.


MEANS OF EGRESS

Left : Figure 3.2.2.2 B

121

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Shows various specifications applicable to doors and doorways. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.121.

Exit Direction

Figure 4.3 Required Door Clearances

Ease of Use: Another important consideration is that the doors should be to use. Forofexample, 1.easy Increase swing door. Use a 180-degree swing door instead of a 90-degree • door They a keyagainst to openthe from the This side they serve. toshould allow not it torequire fully open wall. can be done only if a

is wideshould enough, asbe shown in Plan Figure 4.4. • corridor The hardware also safe and easyBtoofuse. 2.• Create alcove. Recess the doorforce intoto the room, as shown in Plan E of Figure It should not require much manually open the doors. 4.4, so that the walls create an alcove that the door can swing into. (The • alcove Use of mirrors in maneuvering doors or in exit ways should be avoided in general to must allow room.) Opening: The exit doors should not open directly into a flight of stairs. A landing of at least the width of the door should be provided in the stairway at each door. The level of the landing should match the level of the floor it serves. Threshold: The threshold of a doorway is also very important. Usually the floor surface or landing on either side of the threshold should be within a small difference in height (1-2 inch) from the threshold. Fire-rating: If the walls of the corridor in which a door opens are fire-rated, the fire rating also applies to the door. See Figure 3.2.2.2 B for an illustration of these specifications.

*

See Section 3.2.3.2 for further details regarding placement of exit doors.

Means of Egress > Exit Accesses

prevent any confusion regarding the direction of exit.


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Note : Stack effect is the upward movement of smoke due to buoyancy created by the difference of air pressure between the inside and the outside of a building, chimney, flue gas stack, or other container. See the Wikipedia article of The stack effect[6] for further details.

Specifications in NBC[7]: • Exit doorways should be at least 1000 mm wide and 2000 mm high. In assembly occupancy, the width specification changes to 2000 mm. • No door, when opened, should reduce the width of a stairway or landing to less than 900 mm. • Overhead or sliding doors should not be installed at major exits. • To prevent the stack effect of smoke in a stairways and lift lobbies which can lead to quicker spread of fire, fire doors with 2 hours of fire resistance should be provided at appropriate* places along the escape route.

3.2.2.3 Staircases The staircases can be of two types, internal and external. Only internal staircases are described here as external staircases do not fall in the domain of interior design. Another key consideration in interior staircase is to control the pressurization in order to combat the stack effect of smoke. But this also does not fall in the domain of interior design, and is therefore omitted. See NBC[8] for further details. Internal staircases can be of different types such as straight run, curved, winder, spiral, scissor, switchback, and alternating tread stairs. However, some of these may not be allowed as means of egress. It should be noted that the egress staircase should not be built around a lift shaft. Also, the material used to build the stairway should be consistent with the construction type of the building. Exit access stairs connecting more than two floors need fire-rated enclosures. For a large building with several stairwells, one of them may be required to have smoke barriers to serve as an area of refuge. Specifications in NBC[9]: Material: Internal stairs should be constructed from noncombustible materials. Ducting in stairway may be permitted with a 1 hour fire resistance rated enclosure. For high-rise buildings (buildings with 15 m or more height), access to the main staircase should be through a door with at least 2 hour fire resistance. (* This may be reduced to 1 hour for residential dwellings.)

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Note : The width of a stair is measured to the outside edges of the steps. The width of a ramp is measured to the inside face of the handrails.

Width: A staircase in a building with assembly occupancy should be at least 2 m wide, whereas the same in a business or mercantile building should be at least 1.5 m wide. (* The minimum width in residential dwellings, residential hotels, educational buildings, institutional buildings, and the remaining buildings should respectively be 1 m, 1.5 m, 1.5 m, 2 m, and 1.5 m.)

Tread: The minimum tread without nosing should be 300 mm in all three occupancy classes. (* The minimum tread in staircases of residential buildings should be 250 mm, while in other occupancies it should be 300 mm.) The treads should be constructed so as to prevent slipping. Riser: The maximum riser should be 150 mm with at most 15 steps per flight. (* The maximum riser in residential buildings is 190 mm.)

* The term “appropriate” is not defined in NBC, and is open to interpretation.

Ceiling: The minimum headroom under the landing of a staircase and under the staircase should be 2.2 m (see Figure 3.2.2.3 A).


The stairs should have at least 2.2 m headroom at all points.

Handrails and Guards: Handrails should be provided at a height of 1000 mm measured from the base of the middle of the treads to the top of the handrails. Handrails (as well as any beams/columns) should not reduce the width or headroom of the staircase. Guards should be provided where there is sufficient change in elevation but no adjacent wall. See Figure 3.2.2.3 B for an illustration of these specifications. Handrails should be at a height of at least 1000 mm. Handrails should also extend to at least 300 mm on the top and the bottom of the stairway.

Left : Figure 3.2.2.3 A

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Shows minimum headroom specification for stairs.

Note : Handrails are critical during an emergency. When stairs are full of smoke, handrails often are the only guide to an exit.

Left : Figure 3.2.2.3 B Shows handrail and guard specifications for stairs.

Discontinuous Handrails: IBC[10] provides specifications for allowed gaps in handrails. Handrails in assemly occupancies should have gaps at intervals of at most five rows to facilitate access to seating. The gaps should be between 22 inches (559 mm) and 36 inches (914 mm) long, and the handrail should have rounded edges at the break points.

3.2.2.4 Ramps A ramp is a walking surface with a running slope of at least 1:20 (see, e.g., the ADA Standards for Accessible Design[11]). Any measurement smaller than 1:20 is not considered as a ramp. Ramps are used typically where there is a change in elevation and accessibility is required. Changes in elevation should usually be avoided within a single floor. However, if such changes are present and steps are provided, a ramp should also be provided.

Note : There is a distinction between ramps and curb ramps. Curb ramps are typically exterior ramps cut through or leading to a curb. Other ramps can be interior or exterior.

Means of Egress > Exit Accesses

Location: The staircase should be located such that no habitable space or store directly opens into the staircase. No electrical shafts/AC ducts, gas pipes, etc. should pass through or open in a staircase. Lifts should also not open in staircases. In case of a single staircase, the staircase should terminate at the ground floor level and access to the basement should be provided using a separate staircase. This extra staircase should be separated at the ground level by ventilated lobby with discharge points to two different ends through enclosures.


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Ramp design is very similar to the design of a staircase in terms of its capacity and dimension (width and height). In fact, NBC[2] and IBC[12] apply the same codes to both ramps and staircases. Apart from these, slope, landings, and handrails are critical components of a ramp. Slope: Most standards require that the maximum slope of a ramp should be 1:12, that is the ramp should increase 1 m (or cm, or inch) in height at every 12 m (or cm, or inch) in length. According to NBC[13], ramps with at most 1:10 slope should be used. Any greater slope may cause danger of slipping. In certain cases, a slope of 1:8 may also be allowed if the ramp is surfaced with a non-slipping material.

Note : Aisles assume travel in two directions. Aisle accessways assume travel in only one direction.

3.2.2.5 Aisles and Aisle Accessways An aisle is similar to a corridor in that it leads to an exit. The difference is that a corridor is enclosed by full-height walls, whereas an aisle is created by movable furniture (tables, counters, furnishings, equipment, merchandise, and other similar obstructions) or fixed seats. A short portion of aisle that leads to another aisle is called an aisle accessway. The codes usually set a minimum width for both aisles and aisle accessways (see Figure 3.2.2.5 A), and this is different for aisles made of fixed seats and those made of moveable seating or furniture.

Aisles are perpendicular to the seating, and should be at least 1.2 m wide.

Right : Figure 3.2.2.5 A

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Shows minimum aisle and cross-aisle width specification (for Assembly occupancy). Adapted from Ching, F. D. K., and Winkel, S. R. â&#x20AC;&#x153;Building Codes Illustrated: A Guide to Understanding the 2012 International Building Codeâ&#x20AC;? Wiley Publishing, 2012, p.205.

Cross-aisles are parallel to the seating, and should be at least 1 m wide.

The width of an aisle should be sufficient for the number of people that will be using it. Hence, its calculation is similar to the width calculation for other parts of means of egress. It depends on the occupant load, the occupancy classification, the type of furniture creating the aisle, and whether the aisle is flat or sloped. If the aisles are to be designed to meet accessibility standards, the width required might be higher due to the need to maneuver a wheelchair. For this reason, accessible seating is typically provided only along the main aisles.


Assembly buildings: Aisles and aisle accessways are very commonly found in assembly buildings with fixed seats. Due to the large number of occupants, various codes (e.g., IBC[12], NFPA 101[14], NBC[2], etc.) have additional specifications for aisles in such buildings.

3.2.3 Exits Exits determine how many people would be able to evacuate a building and in what manner and how much time. Examples of exits include doorways, corridors, and passageways. These may be connected to internal or external staircases, to a verandah or terraces with access to the street, to the roof of a building, or to a refuge area. An exit may also include a horizontal exit leading to an adjoining building at the same level. However, lifts and escalators are not considered exits.[15] See Figure 3.2.3 A for an illustration of exit within an egress path.

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Note : The required dimensions for stairs and ramps used in Assembly aisleways are different than those for other standard ramps and stairs. Typically, the riser of the stair is shorter and the slope of the ramp is smaller to accommodate the large number of people.

Specifics of exits and egress paths should be analyzed at the beginning of a project, in construction as well as in renovations. There are four specifics which are important: 1. The number of exits, 2. Arrangement of exits, 3. Travel distance, and 4. Exit width. Each of these is described thoroughly in the following.

EXIT โ€ข Exits mark the end of the exit access and the beginning of the exit portion of a means of egress system.

Left : Figure 3.2.3 A Shows exit within an egress path.

3.2.3.1 Number of Exits The number of exits, together with exit width, determine the exit capacity, i.e. how many occupants would be able to evacuate safely. Thus, it crucially depends on the occupant load. While such dependence is minimal or absent in NBC[2], it can be observed in other codes. For example, ยง 1015.1 in IBC[16] describes the required number of exits as a function of both the occupancy classification and the occupant load. The calculation of the required number of exits is particularly interesting for multi-storey buildings, as shown below.

Means of Egress > Exits

Exit Access


150

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Example Note It is not uncommon for a multi-story building to have a large Assembly occupancy on the top floor. If it has the largest occupant load it could dictate the exit requirements for the whole building.

Figure 4.16 indicates the outlined section of a multi-story building. It calls out the

Multi-storey occupant loadbuildings: for each floor and the number of exits based on these occupant

loads (using the code breakdown shown earlier). As you can see, the fourth floor

hasdetermine the largest the occupant load, total of 1020, and, therefore, requires To number of with exitsarequired for an entire building, first the the largest number of exits. The code specifies four exits for any occupant load over number of exits should be calculated at each floor or storey separately using 1000. Asoccupant a result, every below it must have fourthat exits, though its own load.floor Then, it should bealso cautioned theeven number oftheir exits occupant loads specify fewer exits. Four separate exit stairs that are continuous should not decrease as one proceeds along an egress path towards the public from the fourth to the first floor would meet the requirement. The first floor way. That is, the number of exits at a floor should not be less than the number would require the exit doors to be located in four separate locations. of exits at any floor. the Thisfourth is usually by having oroccumore Notice thehigher floors above floor.accomplished Each of these floors has aone lower contiguous exit stairways that open to every floor they pass through. Figure pant load than the fourth floor. Since these floors are above the fourth floor, fewer 3.2.3.1 A illustrates thisseventh calculation example building. exits can be used. The floorfor hasanthe largestmulti-storey occupant load (above the

Right : Figure 3.2.3.1 A Shows how the required number of exits on each storey is calculated in multi-storey buildings. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.150.

Note : If an interior project involves only a part of a building or floor, the number of exits and total exit width for that part should be determined. Note that this may affect (and require changes in) the number of exits or exit widths in other parts of the building as well. Figure 4.16 Number of Exits Example (Multi-Story Building)

Specifications in NBC[17]: Two types of buildings should have a minimum of two staircases.

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• All buildings with height of 15 m or more, i.e. all high-rise buildings. • All buildings used as educational, assembly, institutional, industrial, storage, and hazardous occupancies, and mixed occupancies with any of the aforesaid occupancies, having area more than 500 m2 on each floor. Further, at least one of the two aforementioned staircases* should be adjacent to an external wall and should open directly to the exterior, to an interior open space, or to an open place of safety.

* Earlier section 3.2.2.3 described interior staircases which may be used as exit accesses. But the staircases mentioned here are specifically exit staircases situated inside the building.

Finally, there are certain specifications that are applicable to buildings with specific occupancy classifications.[18] (As the focus of this thesis is restricted to Assembly, Business and Mercantile occupancies, only those specifications are described below.)

• Assembly (Group D): There are two special specifications for sub-divisions D-1 and D-2.


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• Sub-division D-1: Every place should have at least four separate exits as far from each other as possible. At least half of the exits should directly lead to outdoors, possibly through exit ways that are completely separated from exits serving other parts of the building. • Sub-division D-2: Every place should have at least two separate exits as far from each other as possible. If the occupant load is more than 600, the required number of exits is three. • Business (Group E): Every floor, including basements that are used for office purposes or for uses incidental to office purposes, should have at least two exits. • Mercantile (Group F): Every part of every floor (including basements) should have access to at least two separate exits. These exits should be as far from each other as possible. Further, the paths of travel to these exits starting from any interior point should be different, except for the first 15 m of the path which can be common.

3.2.3.2 Arrangement of Exits After the number of exits, another important detail is their location (arrangement). The arrangement of exits should be such that it satisfies a variety of criteria. First, all exits should provide contiguous means of egress, and starting from any point in the interior of a building, one should be able to reach an exit without having to pass through any other occupied space. Further, the arrangement is usually restricted through maximum travel distance. For example, Table 3.2.3.2 below specifies what the maximum travel distance to an exit should be from any interior point of any floor. If a floor plan requires traveling a distance greater than this, changes should be made to the floor plan, e.g., by moving a wall or adding a new exit. Further, the travel distance to an exit from the dead end of a corridor should be at most half of the distance specified in the same table.

Travel Distance for Occupancy and Type of Construction Group of Occupancy Maximum Travel Distance (m) (All Construction Types) Assembly (D) 30.0 Business (E) 30.0 Mercantile (F) 30.0

Travel Distance[19] The travel distance is the distance to be travelled from any point in a building to a protected escape route, external escape route, or final exit.

Left : Table 3.2.3.2 Describes the maximum travel distance in the three occupancy types under consideration in this thesis. Adapted from “The National Building Code of India”, 2005, BIS, Part 4, p. 27.

As mentioned previously, in case of multiple exits NBC[2] suggests putting the exits as far from each other as possible. Several other codes (see e.g., § 1015.2.1 in IBC[16]) put a quantified restriction on this, typically known as the half-diagonal rule. Under the half-diagonal rule, at least two of the exits on a floor should be separated by a distance of at least one-half of the longest

Means of Egress > Exits

NOTES: 1. For fully sprinklered building, the travel distance may be increased by 50 percent of the values specified. 2. Ramps shall be protected with automatic sprinkler system and shall be counted as one of the means of escape.


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diagonal in the floor plan. This is illustrated in Figure 3.2.3.2 A. This may be relaxed to one-third for sprinklered buildings. The longest diagonal is measured differently in different cases. MEANS OF EGRESS

Right : Figure 3.2.3.2 A

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Illustrates the half-diagonal rule in various situations. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.161.

Note : While designing a number of different tenant spaces in the same building, the travel distance should be measured for each tenant. It does not matter if the tenants are all the same occupancy. If they are separated from each other by a demising wall, they should be treated separately.

Figure 4.20 Half Diagonal Rule Example: Building • In tenant spaces, this is measured as the longest possible diagonal (in a straight line) connecting one corner of the floor plan to another corner. This is otherwise unaffected by the shape and size of the space or existence of surrounding spaces, as shown in Figure 3.2.3.2 A above.

• When a building has exit enclosures, the distance between the corresponding exits is measured differently. For example, in case of two exit stairs connected by a fire-rated corridor, the distance between the two stairs is measured along the path of travel, as demonstrated in Figure 3.2.3.2 B. • Finally, the distance is usually measured from the center of the door (e.g., IBC[12]), however, some codes allow measuring the distance from the edge of the door (e.g., NFPA 101[14]).

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THE CODES GUIDEBOOK FOR INTERIORS

Left: Figure 3.2.3.2 B

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Illustrates travel distance measurement and the half-diagonal rule when the building has exit enclosures. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.162.

Travel Distance Figure 4.21 Half Diagonal Rule Example: Tenant and Floor

As per NBC[19], the travel distance is measured as the distance to be travelled from any point in a building to a protected escape route, external escape or space theexit. exit that it. Two types of travel distance regulated by the route, or to final Thisserves distance is measured on the floor are along the centercodes. First, the codes limit the length of travel distance from within a single line of the natural path of travel (see Figure 3.2.3.2 C). If the exit is accessed space to the exit access corridor. This is known as a common path of travel, through fire-resistance then only the distance to the corridor becauseaall the occupantsrated of thatcorridor, space will have to travel approximately the same isdirection counted.before The latter is known as common path of travel because all occuthey come to two options for exiting. (See the section on pants of a space to travel the same toalso reach the exit access Common Path ofhave Travel on page 169.) Thepath codes regulate the lengthcorridor, of travel from where they might have an option to choose from multiple exits.These are distance from anywhere in a building to the exit of the building or floor. separate travel distance calculations and the information is located in different areas of the codes. The travel distance the is measured Travel distance from within a single space is basically determined same way along a natural and unobstructed Common path by the building codes and the LSC. Travel distance within a single space is espepath of egress travel. of travel

Left : Figure 3.2.3.2 C Illustrates travel distance calculation as well as common path of travel. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.205

The final distance to be used for the purpose of Table 3.2.3.2 should be the maximum travel distance from any point in the building.

Means of Egress > Exits


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3.2.3.3 Exit Width Similarly to the number of exits, the exit width also depends on the occupancy classification and the occupant load. The codes usually define the total exit width required, which can be determined for the whole building, each floor, or even individual spaces within a floor. This total width is then to be divided uniformly across all exits in the building, floor, or space under consideration. But for a single room, the total width calculated would determine the width of the door. For multi-storey buildings, the exit sizes are determined by the floor with the largest occupant load. Table 3.2.3.3 below gives the specification for the total exit width as a function of the occupant load and the occupancy classification.

Right : Table 3.2.3.3 Describes the maximum number of occupants per unit exit width (500 mm) in the three occupancy types under consideration in this thesis. Adapted from “The National Building Code of India”, 2005, BIS, Part 4, p. 27.

Occupants per Unit Exit Width Group of Occupancy Number of Occupants per Unit Exit Width (500 mm) Staircase Ramps Doors Assembly (D) 40 50 60 Business (E) 50 60 75 Mercantile (F) 50 60 75 Note: 1. For Table 3.2.3.3 above, the unit of exit width is 500 mm. A width of 250 mm is considered ½ unit, but widths less than 250 mm are ignored. 2. When a horizontal exit (see Section 3.2.3.4) is provided in buildings of mercantile, storage, industrial, business and assembly occupancies, the figures of Table 3.2.3.3 above may be increased by 50 percent and in buildings of institutional occupancy they may be increased by 100 percent.

3.2.3.4 Types of Exits Two primary types of exits that can be used in a building are: • Exterior Exit Doors, • Horizontal Exits.

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Exterior Exit Doors: An exterior exit door is a doorway in an exterior wall of the building that typically leads from the ground floor of the building to a public way. An exterior door is usually not required to be rated unless the exterior wall is rated because of the potential exposure to fire from an adjacent building. Horizontal Exits: As per NBC[19], a horizontal exit is an arrangement which allows alternative egress from a floor area to another floor at or near the same level in an adjoining building or an adjoining part of the same building with adequate fire separation. Fire separation is provided by fire and smoke barriers. While their usual purpose is to limit the spread of fire/smoke, here it is to provide a protected exit. A horizontal exit is different from the other exits because it does not lead to the exterior of a building, but rather to a safe area of refuge (see Figure 3.2.3.4 A). While typically horizontal exits do not involve a change in level between the two ends, a small difference may be incorporated by using a ramp with a very small slope; however, steps should not be used. When the exit leads to another building, balconies and bridges may be used. The doors should be openable from both sides at all times, and should swing in the direction of the exit. Horizontal exits should not be the only type of exit in a building.


area of refuge for the other area. When the horizontal exit leads to another building, such as in Plan C of Figure 4.13, structural features such as balconies and bridges can also be used. In this example, a horizontal exit is used for Building A Below: Figure 3.2.3.4 B

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Shows area of refuge specifications. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.167

Area of Refuge

Figure 4.13AHorizontal Exit Examples Above : Figure 3.2.3.4 Shows various configurations of horizontal exits and areas of refuge. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.141.

Note : When an area of refuge is used in conjunction with an exit stair, the minimum stair width as required by the codes will usually increase.

Refuge Area:

Dimensions: The refuge area should be of at least 15 m2 or an area equivalent to 0.3 m2 per person to accommodate the occupants of two consecutive floors, whichever is higher. Location: There should be one refuge area immediately above 24 m for floors between 24 m and 39 m. There should be another refuge area on the floor immediately above 39 m and afterwards one every 15 m. These refuge areas should be on the periphery of the floor or preferably on a cantilever projection. They should also be open to air at least on one side and protected with suitable railings.

Means of Egress > Exits

Refuge area (also known as area of rescue assistance) is a space where people unable to use stairways can safely wait for assistance in case of an emergency. This area is protected by fire and/or smoke partitions. Refuge areas are usually provided next to or in an exit stairway, or at elevator lobbies. It is common for refuge areas to be wheelchair-accessible. When they are provided in an exit stairway, the landings are enlarged or have an alcove to accommodate one or more wheelchairs (the exact number depends on the occupant load) without blocking the mean of egress (see Figure 3.2.3.4 B). NBC[20] states that buildings with 24 m or more height should be provided with a refuge area. The specifications of dimensions and locations of refuge areas are given below.


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Specifications in NBC[20]: • The width of a horizontal exit should be the same as for the exit doorways. • The horizontal exit should be directly connected to the fire escape staircase for evacuation. • The horizontal exit should also be equipped with at least one self-closing fire door with at least 1 hour fire resistance. • If a ramp is used to match the levels on two ends of a horizontal exits, its slope should not be more than 1 in 10 m.

3.2.4 Exit Discharges An exit discharge is the part of a means of egress that connects an exit with a public way. It is typically found on the ground floor of a building. The required fire rating of an exit discharge would vary, depending on its type and location. In some types of exit discharges, the enclosure may have a lower rating than the exit it serves. Main lobby, foyer/vestibule, and discharge corridors are the types exit discharges used in the interior of a building, whereas egress court and small alley or sidewalk are used outside a building (hence not explained here). The width of an exit discharge is typically determined using the width of the exit it is connected to, though accessibility standards may specify greater width. When more than one exit leads into an exit discharge, the width of the exit discharge is the sum of the exit widths. Two types of exit discharges that are important for interior designers are described below. Main Lobby: One of the most common interior exit discharges is the ground floor lobby of a building. For example, an stair may lead to the main lobby. In this case, the space between the door of the stair and the exterior door is the exit discharge. However, not every lobby may serve as an exit discharge. An exit discharge should occur after a protected exit, and should lead to the exterior door or to the exterior of the building. Foyer or Vestibule: An interior exit discharge may also include an enclosed foyer or vestibule. These are small enclosures on the ground floor of a building between the end of a corridor and an exterior door. Small foyers/ vestibules may not be required to have a high fire rating, and hence may be considered an exit discharge instead of an exit passageway.

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Discharge Corridor: Sometimes, an exit stair empties into a non-fire-rated corridor, which becomes an exit discharge. The codes sometimes require such corridors to be sprinklered.

3.2.5 Egress Signage and Illumination Egress signage and illumination concerns mainly three things. 1. Installing signs to aid the occupants find egress paths and exits. 2. Illuminating these signs, and 3. Illuminating the egress paths including corridors and staircases.


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The chapter concludes by describing these in detail. Note that egress signage and illumination are crucial because without them the rest of the egress facilities are useless. They are even more important when there are multiple exits and/or the egress paths are not obvious.

3.2.5.1 Egress Signage Egress signage consists of a variety of signs that are helpful for egress in case of an emergency. These include exit signs and other exit related signs. For egress signage, accessibility standards may have specifications in addition to those given in the building codes, e.g., specifications related to lettering heights, mounting locations, colour contrast, and in certain cases, the use of Braille etc. Perhaps the most important of all egress signage is the exit sign. Exit Signs: The purpose of exit signs is to lead the occupants to the nearest exit or in some cases an alternative exit. They are easy to identify with the word “EXIT” written on them. They are used whenever a floor or space has two or more exits, and are placed on the doors of stair enclosures, exit passageways, and horizontal exits. Such signs, possibly with added directional arrows, should also be placed on doors for exiting a space or area where the egress direction is unclear, e.g., when a corridor changes direction. See Figure 3.2.5.1 A.

Note : When double doors are used as an entry into a space, the sign is required on the wall to the right of the door.

Exit signs should be placed at a regular interval, so that every point is within a reasonable distance to its nearest exit sign. This distance is sometimes specified in the codes. Exit signs are usually ceiling mounted, but sometimes they can be located near the ground so that they can be seen even when smoke gathers near the ceiling.

Exit sign with directional arrow

Shows exit signs, their placement, and placement of exit signs with directional arrows. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.177.

4” (102 mm) to frame on latch side Exit signs are usually ceiling mounted, but sometimes they can be located near the ground so that they can be seen even when smoke gathers near the ceiling.

Means of Egress > Exit Discharges > Egress Signage and Illumination

Left : Figure 3.2.5.1 A


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Specifications in NBC[21]:

Below : Figure 3.2.5.1 B Shows various methods for marking egress paths. Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.195.

• All signs should be clearly visible and the route to reach the exits should be clearly marked. • Signs should be posted to guide the occupants of the floor concerned. These signs should be illuminated as explained in Section 3.2.5.2 below. It also requires the exit signs to be green in colour. • Exit signs should be placed at all exits, emergency exits and escape routes. These signs should comply with the graphic specifications of good practice [4(16)]. 1” marking for handrails and extensions at top of rail, continuous except for a maximum of 4” gaps.

Exit Marking

All steps should have 1” to 2” (25 to 51 mm) wide stripes along their leading edge, extending for their full length.

Obstacles such as standpipes or structural elements at or below 6’-6” (1981 mm) and projecting more than 4” (102 mm) into the egress path should be outlined in marking tape with 45-degree alternating dark and luminous patterns.

The leading edges of landings should have stripes with the same size and location criteria as for stair treads. Stair landings should have 1” to 2” (25 to 51 mm) wide demarcation lines, possibly mounted on the floor or wall. Where wall mounted and coming to a stair, they should drop vertically within 2” (51 mm) of the stair tread or riser. When wall mounted, their bottom edge should be within 4” (102 mm) of the floor. A maximum of 2” (51 mm) gap Top and side of door frame marked with 1” to 2” (25 to 51 mm) wide stripes. Door hardware area marked with at least 16 square inches (406 mm2) of luminous material “Running Man” exit sign as per NFPA 170 Standard for Fire Safety and Emergency Symbols. Min. 4” (102 mm) high

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No demarcation stripe at final exit door from interior exit stairway.

Should be mounted at centerline of door, at most 18” (457 mm) from finish floor level to top of sign.


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Signs on Staircases: According to NBC[22], • A staircase should have an exit sign with arrow indicating the way to the escape route. • This should be at a suitable height from the floor level and should be illuminated by electric light connected to corridor circuits. • The signs should be flush with the wall and so designed that no mechanical damage may occur to them due to moving of furniture or other heavy equipment. • Every landing should have a board displaying the floor number. This should be placed on the wall immediately facing the flight of stairs and nearest to the landing, and should be at least 0.5 m × 0.5 m in dimension. See Figure 3.2.5.1 B for various ways of marking egress paths. Other signs are needed when the means of egress are confusing. For example, a regular door or stairway that may be confused with an exit door or stairway should be labelled “NO EXIT”. The label may additionally specify what the door or stairway leads to. Doors that should remain locked in case of a fire may be labelled “KEEP DOOR CLOSED”. Signs may also be placed to help the occupants locate the nearest refuge area. Other signs include signs that help the occupants orient themselves in the space, e.g., floor levels and numbering of stairs.

3.2.5.2 Emergency and Escape Lighting

Like exit signage, emergency lighting is typically required whenever two or more exits are present. It should be provided at all exits and any aisles, corridors, passageways, ramps, and lobbies leading to an exit. It should be powered by a source other than the one supplying normal lighting. According to NBC[24], emergency lighting should turn on within 1 s of the failure of normal lighting, and should be capable of running till at least 1 hour (at least 30 minutes even for the smallest premises). General exit lighting, exit signs, and area of refuge signs should also be lit at all times. Specifications in NBC[24] : Placement of escape lighting: Escape lighting should clearly indicate the escape routes. It should also help locating fire alarm call points and fire-fighting equipment. Escape lighting should be placed at the following locations. • • • • • •

Near each intersection of corridors, At each exit door, Near each change of direction in the escape route, Near each staircase so that each flight of stairs receives direct light Near any other change of floor level, Outside each final exit and close to it,

* Note: ‘Near’ = within 2 m measured horizontally.

Means of Egress > Egress Signage and Illumination

An important part of illumination in means of exit is the emergency and escape lighting. According to NBC[23], emergency lighting is the lighting provided for use when the supply to the normal lighting fails. Escape lighting is the part of emergency lighting which is provided to ensure that the escape route is illuminated at all necessary times, for example, at all times when persons are on the premises, or at times the main lighting is not available, either for the whole building or for the escape routes.


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* Note: ‘Near’ = within 2 m measured horizontally.

• Near each fire alarm call point, • Near fire-fighting equipment, and • To illuminate exit and safety signs. Emergency Lighting Luminance: The wiring of emergency lighting should be of high quality so that it provides high quality of service. For example, a failure in one luminaire should not affect the system as a whole. The luminaires and their fittings should be non-flammable, and should be mounted as low as possible, but at least 2 m from the floor level. The floors of areas covered for the means of egress should be illuminated to at least 1 ft candle (10 lux) at the floor level. In auditoriums, theatres, concert halls and such other places of assembly, this may be reduced to 1/5 ft candle (2 lux) during periods of performances. The floor level luminance at the centreline of an escape route should be at least 10 lux. If the route is at most 2 m wide, 50 percent of the route width should be lit to a minimum of 5 lux.

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End Notes 1. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 26. 2. The National Building Code of India. Bureau of Indian Standards, 2005. 3. Ibid. Part 4, p. 28. 4. Ibid. Part 4, p. 27. 5. The International Building Code. International Code Council, 2012. p. 265. 6. Stack effect. Wikipedia. 4 March 2014. <http://en.wikipedia.org/wiki/Stack_effect >. 7. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, pp. 27-28. 8. Ibid. Part 4, pp. 29-30. 9. Ibid. Part 4, pp. 28-29. 10. The International Building Code. International Code Council, 2012. P. 278. 11. 2010 Ada Standards for Accessible Design. United States Department of Justice, 2010. 12. The International Building Code. International Code Council, 2012. 13. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 31. 14. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. 15. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 26. 16. The International Building Code. International Code Council, 2012. p. 262. 17. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, p. 27. 18. Ibid. Part 4, pp. 49-61. 19. Ibid. Part 4, p. 8. 20. Ibid. Part 4, p. 31. 21. Ibid. Part 4, pp. 26, 31-32. 22. Ibid. Part 4, pp. 28-29. 23. Ibid. Part 4, p. 7. 24. Ibid. Part 4, pp. 31-32.


3.3 Plumbing and Mechanical Systems

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In This Part, 3.3.1 Plumbing Systems 3.3.2 Mechanical Systems 3.3.2.1 Exhaust Requirements

3.3.2.2 Plenum Requirements 3.3.2.3 Duct Requirements

Plumbing and mechanical systems are quite complex and have detailed code specifications. Most of these specificationsâ&#x20AC;&#x201D;which are certainly of interest to engineersâ&#x20AC;&#x201D;do not relate much to interior design. Further, the code specifications for these systems are mainly standards for their installation, most of which are not critical to building and life safety. Hence, these specifications are beyond the scope of this thesis. However, plumbing and mechanical systems respectively include sprinkler and ventilation systems, which are crucial for fire and smoke protection, as evident from Section 3.1. Hence, this section focuses on the specifications related to sprinkler systems and mechanical ventilation systems.


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3.3.1 Plumbing Systems Code specifications for plumbing systems also provide specifications for sprinkler systems, which are critical for fire protection. An interior designer should know the basics of these specifications because many decisions regarding sprinkler systems (such as the type, number, locations etc.) fall under the domain of interior design. For detailed plumbing specifications, the International Plumbing Code[1] can be referred in addition to the relevant parts of NBC[2], IBC[3], and NFPA 5000[4]. As mentioned in Section 3.1, two popular types of sprinkler systems are wet-pipe and dry-pipe systems. While wet-pipe system is used almost everywhere, dry-pipe system is used where there is chance of freezing (e.g., in cold attics, unheated parking garages etc.). In dry pipe systems, air is pressed to hold back water, and when the sprinkler is activated, the air is released and the water flows. The compressor used thereby are small, but sometimes noisy, and therefore should be installed in locations carefully planned to avoid noise problems. In commercial buildings, conventional sprinkler systems are designed to serve the "most remote 1500 sq. ft." area. An area this large usually has 7-12 sprinklers, each delivering 6 gallons per minute (gpm). Together with 250 gpm of fire hose, this adds up to about 320 gpm requirement for up to 90 minutes, which would require a rather large (4â&#x20AC;? or 6â&#x20AC;?) pipe. This illustrates the difficulty in having even 12 sprinklers running simultaneously. It is almost impossible to have all sprinklers in the building running simultaneously, as often shown in the movies.

Note : ESFR systems are only used where they are required (mostly in storage areas) because they are very costly.

This also means that standard sprinkler systems are not designed to put out fires, but rather slow it down till the fire department arrives. There are special sprinkler systems (known as ESFR-early suppression) that are designed to put out fires. but they require much higher flow rates (almost double). This requires fire pumps and more sprinklers per given area.

3.3.2 Mechanical Systems

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Interior designers should know the basics of mechanical systems because they should be able to coordinate the locations of supply diffusers, return grilles, light fixtures, clearance for mechanical equipment, etc. with the mechanical engineer. This coordination should be done at the beginning of the project as these decisions typically affect ducts and ceiling heights. For detailed mechanical specifications, the International Mechanical Code[5] can be referred in addition to NBC[2]. Mechanical systems are also referred to as HVAC (heating, ventilating, and air conditioning) systems. Among these, ventilation system is an important system of interest to interior designers. The main purpose of the ventilation system is to replace the air in the building (which may contain toxic gases such as carbon dioxide and carbon monoxide as well as flammable substances such as grease) with fresh outside air. Two types of ventilation systems are primarily used. Natural ventilation. By opening windows and/or doors or by using louvers (openings).


• Mechanical ventilation. By using fans to force bad air out and bring fresh air in.

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From life safety viewpoint, there may be a danger in having only natural ventilation. For example, when all doors and windows are closed, natural ventilation would not work. In emergency, this may endanger the occupants substantially. Therefore, the codes require mechanical ventilation system and regulate the size of the vent and the amount of fresh air required based on the floor area, the occupant load, and the occupancy type. The codes recommend mechanical ventilation in special rooms such as computer or server room. Therefore, an interior designer might want to locate such rooms near an exterior wall for easier ventilation. Other examples requiring ventilation include atriums and vestibules. TYPES OF MECHANICAL SYSTEMS There are three main types of mechanical systems. 1. All-air systems: These systems use centrally located fans to circulate are and are most popular in large buildings. Examples include the more popular variable air volume system (VAV), and the less popular constant air volume system (CAV). 2. All-water systems: These systems circulate air in each room locally by a convector or a fan, and have water pipes running between such rooms. Examples include the popular electric baseboard convector system, and less popular fan-coil terminals, closed loop heat pumps, hydronic convectors, etc.. 3. Air and water systems: These are hybrid systems that use central fan to circulate fresh air, and the air is heated or cooled using water. An example is the air-water induction system. Selection of appropriate system depends on a number of factors, including the size and use of the building, the number of occupants, the cost, and the maintenance. Most mechanical systems use ductwork to supply the air, registers to distribute the air, and grills/ductwork to retrieve the return air. Other buildings use a plenum system, whereby the open space above the suspended ceiling and/or the enclosed vertical shafts are used to collect the return air.

Below, three primary components of a ventilation system are described that affect the practice of interior design. • Exhausts • Plenums • Ducts

An exhaust system removes the air from the space that may contain smoke, germs, chemicals, odors, or other unhealthy or contaminated components. This has special importance in hazardous occupancies where the exhaust should typically change the air a few times per hour and should create a specified air flow route. Exhausts are also required in toilets, bathing facilities, designated smoking areas, cloth dryers, and (commercial and sometimes residential) kitchens. Pipes or ducts connected to the exhaust should typically open in the exterior of the building. These are sometimes limited in length and the number of 45/90 degree bends. Special consideration should be given to the air flow route as it may affect floor/ceiling assemblies, vertical shafts, etc.

Plumbing and Mechanical Systems

3.3.2.1 Exhaust Requirements


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Commercial exhaust systems See Figure 3.3.2.1 for a commercial exhaust system. Commercial kitchens use exhaust systems with two types of hoods: Type I and Type II. • Type I hoods are used for grease-removal. Since grease is a flammable substance, they typically have fully automatic fire-suppression systems that can detect and put out substantial fires that are not typical even in a commercial kitchen. Due to the chance of fire originating due to grease and spreading throughout the duct, ducts in this case are constructed using heavy steel and should be fully welded joints to prevent fire from escaping into the surrounding structure. They should also have substantial (up to 18”) separation from combustible materials. This makes it difficult to use them in wood-framed buildings. • Type II hoods are used in case of heat and moisture (thus used above dishwashers and light-duty appliances that do not produce grease or smoke). These hoods are designed assuming that commercial equipment will be used. Residential equipment have different characteristics. Therefore, in case residential equipment is used, an interior designer should be consulted.

Exhaust hood for commercial kitchen Right : Figure 3.3.2.1 Shows exhaust hood in commercial kitchens as part of commercial exhaust system. CREDIT: http://starengineeringworks.com/ exhaust.html‎

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3.3.2.2 Plenum Requirements Plenum An enclosed portion of the building structure, other than an occupiable space being conditioned, that is designed to allow air movement, and thereby serves as part of an air distribution system.

Most all-air type HVAC systems use either a duct or a plenum for return air. Recently, the use of plenums has grown quite popular due to low costs. Open space between the ceiling and the floor above acts as a ceiling plenum to collect return air if no other / few other ducts are present (see Figure 3.3.2.2 (b)). Plenums should only be used locally, e.g., one plenum should be limited to the space of a single tenant. If a plenum spans multiple tenants’ spaces, dampers should be used at the openings in the wall between two tenant spaces to stop air flow. There are two major implications of using return-air plenums.


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1. Combustible materials should not be used in plenums, e.g., most wiring (including those of fire alarms and other security systems), plumbing piping, HVAC piping, fire protection piping, etc. 2. Plenums should be as open as possible. Thus, fire walls that extend from the floor through the ceiling to the deck above typically cannot be used in the middle of a plenum. Walls that stop at the underside of the ceiling (quite common in commercial offices) are ideal for plenums. Some projects involve supply air plenum below the floor (see Figure 3.3.2.2 (a)) and some use exhaust plenums as well, although these are far less common.

(a) Left : Figure 3.3.2.2 (a) Shows the use of floor plenum for supply air. (b) Shows the use of ceiling plenum for return air. CREDIT: (a) http://cbe.berkeley.edu/underfloorair/exampleLayout.htmâ&#x20AC;&#x17D; (b) http://cbe.berkeley.edu/underfloorair/techoverview.htmâ&#x20AC;&#x17D;

Floor Plenum Ceiling Plenum

3.3.2.3 Duct Requirements When ducts are used for supply air or return air, the codes place fewer restrictions on the materials used, but place restrictions on the ducts themselves. For example, firestops / fire dampers and smoke dampers should be used when the duct passes through a fire rated wall or a smoke barrier, respectively.

Note : Only rigid ducts are allowed to pass through a fire rated wall.

Plumbing and Mechanical Systems > Mechanical Systems

(b)


Smoke dampers may also be required when a wall is considered a smoke barrier. (See Chapter 5.) Figure 7.12 indicates the use of a fire damper on a duct that is passing through a fire-resistance-rated wall assembly. The firestop in this case is fire-rated caulk or sealant used continuously around the fire damper on each side In case of athrough duct penetrating floor/ceiling assemblies, a when damper or shaft where it passes the wall. The building codes also specify a damper or enclosure may be required. See Figure 3.3.2.3. The codes usually specify the shaft enclosure is required around a duct that penetrates a floor/ceiling assembly. sizethat of the ducts, thecodes typesmay of rated andnewer mounting and (Note performance allow materials the use ofallowed, some of the fire-rated clearance specifications. In some cases, smoke detectors may be required duct wrap as an alternative if proper testing and installation can be shown.) inside the ducts. codes specify such things as the size of the ducts, types of The mechanical rated materials allowed, and mounting and clearance requirements. For example,

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Right : Figure 3.3.2.3 Shows plumbing pipe and duct passing through ceiling plenum, and the protections required in this case. Adapted from Harmon, S. K., and Kennon, K. E. â&#x20AC;&#x153;The Codes Guidebook for Interiorsâ&#x20AC;? John Wiley & Sons, 2011. p.290.

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Figure 7.12 Mechanical/Plumbing Penetrations in Rated Wall Assembly

End Notes 1. 2. 3. 4. 5.

The International Plumbing Code. International Code Council, 2012. The National Building Code of India. Bureau of Indian Standards, 2005. The International Building Code. International Code Council, 2012. NFPA 5000: Building Construction and Safety Code. National Fire Protection Association, 2012. The International Mechanical Code. International Code Council, 2012.


3.4 Electrical Systems

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In This Part, 3.4.1 Electrical Panels and Rooms 3.4.2 Electrical Cabling and Conduit 3.4.3 Electrical Boxes 3.4.4 Grounding and Circuit Interrupters 3.4.5 Light Fixtures 3.4.6 Special Electrical Systems

Inadequate electrical systems such as faulty wiring are a major cause of fires in buildings. Hence, preventing fires in various parts of an electrical systemâ&#x20AC;&#x201D;panel board, cabling, conduit, outlets, fixtures, etc.â&#x20AC;&#x201D;is of prime importance in fire protection. This chapter describes various considerations for the aforementioned parts of an electrical system that relate to building and life safety. An interior designer should be aware of the basic concepts to coordinate with an electrical engineer or an electrical contractor regarding locations and types of outlets, fixtures, equipment, and appliances, as well as the location of equipment rooms.


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The electrical system within the building is known as the premises wiring system, on which code specifications typically apply; the wiring from the utility company till outside of the building is not regulated by the codes. The premises wiring system extends from the main electricity connection through panel boards in a central electrical room to all the outlets throughout the building.

3.4.1 Electrical Panels and Rooms There are three major types of panel boards. Note : Typically electrical panel rooms cannot use water sprinklers. Dry or other types of non-water sprinkler systems should be used.

Note : An electrical panel is a common place for a fire to start. Hence, while designing interiors, it should not be placed near any means of egress component.

1. The service entrance switchboard is typically the largest of all switchboards, located in an electrical panel room. This is the main connection from utility company. Due to its size and high voltage, it requires sufficient (typically[1] 900 mm x 750 mm) floor space clearance. Other equipment such as transformers in the panel room may also need similar clearances. The panel room itself should be fire rated and ventilated (to control the heat buildup from the equipment). 2. There might be smaller panel boards on each floor, typically located in an electrical closet or cabinet, in or against a wall. Such electrical closets / cabinets usually do not need to be fire rated. In a multi-storey buildings, these boards are situated in a single vertical line. 3. To further distribute the power across a floor, even smaller switchboards or panel boards may be used.

3.4.2 Electrical Cabling and Conduit

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In addition to the panel boards, the wiring is a critical part of the electrical system in a building. This is more critical because wiring typically passes through many building elements. When electrical wiring is installed, the diameter of any hole created for the passage of the cable cannot be more than 1/8 inch (3mm)larger than the diameter of the cable, conduit, or other device passing through the hole. When These wires pass through a rated floor, ceiling, or wall assembly, the building codes require the use of a rated firestop. (See Chapter 5 for more information on fire stops.) In some cases, an electrical cable may be allowed to run on its own, while others will require the use of a protected enclosure such as a conduit or raceway. It typically depends on the type of cable and the construction type of the building (see Chapter 3), but it can also depend on the location of the cable within a building. For example, if a cable is run within a rated assembly, it typically must be within a conduit. Certain jurisdictions have special requirements or restrictions as well. Various cables, conduit, and raceways are explained next.

Cabling Cables or their sleeves should not produce toxic fumes when exposed to fire. For this reason, mostly noncombustible material should be used in the cable. Cables passing through ducts, plenums, and other air handling spaces have stricter requirements because the air flow in such spaces might strengthen the fire and spread the smoke.


Conduit Conduit is a popular alternative to wiring in most commercial buildings. See Figure 3.4.2. Conduit, also known as tubing, is a fire-rated metal piping to protect plastic cables. Conduits may provide grounding effect, and may protect building materials from heat produced by the wiring. Non-metallic conduits typically should not be used, especially in fire-rated assemblies. While many similar wires may pass through a single conduit, the use of electrical wires together with communication cables within a single conduit is often not allowed. THE CODES GUIDEBOOK FOR INTERIORS

Left : Figure 3.4.2 Shows conduit passing through ceiling plenum and wall. Adapted from Harmon, S. K., and Kennon, K. E. “The Codes Guidebook for Interiors” John Wiley & Sons, 2011. p.304.

Figure 8.3 Electrical Penetrations in Rated Wall Assembly

Circuitry For fire protection, the codes should be referred for allowed voltage and redirected. under-floor may be added after the initial amperageOther of power throughraceways the circuitry. These quantities affect constructhe numtion of a building as part of the finished floor assembly. ber and types of equipment, lighting, and other appliances used in a space. Raceways may alsoequipment be mounted on walls for dedicated easy access. For example, In some cases, heavy therefore need circuitry. wireways that are enclosed with removable covers can be installed around the perimeter of a factory to allow access to the cables as locations of equipment 3.4.3Openings Electrical Boxes change. (e.g., knockouts) in the wireways allow the cabling to be directed to different locations when needed. Other types of raceways can be used boxes penetrate wall or ceiling toElectrical cover a cable rundo onnot thecompletely surface of the wall. (Certain codes mayassemblies, restrict the but use membrane penetrations (seeassemblies.) Section 3.1.3.3). There are three main ofcreate raceways when used with fire-rated types of electrical boxes: outlet boxes, switch boxes, and junction boxes. Among these, outlet and switch boxes are more important for interior designers. Electrical boxes located in fire-rated walls, floors, or ceiling assemblies should satisfy the following requirements.

Electrical Systems

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• Type: It should typically be a metal box of at most 16 square inches (10300 sq. mm). • Quantity: The total number of boxes in a single wall or ceiling are limited due to restrictions on the total opening in a rated wall or ceiling (see Section 3.1.3.2). • Location: Two boxes should either be separated by 24 inches (610 mm) or should have fireblocking between them. • Firestopping: Firestops should be used to seal the penetration created by the box.

Outlet Boxes Outlet boxes are usually used as electrical receptacles (wall or floor mounted) or as light fixtures (wall or ceiling mounted). The clearance between the box and the board in which it is mounted should not exceed 1/8 inch (3 mm).[1] See Figure 3.4.3 (a).

Note : In case of automatic switch sensor, a manual switch should be provided as well as part of the device.[1]

Switch Boxes Switch boxes are typically wall mounted and control various outlets. The specifications for switch boxes (e.g., the clearance specification between the box and the board in which it is mounted) typically match the specifications for outlet boxes. See Figure 3.4.3 (a).

Junction Boxes Junction boxes are between switch boxes and outlet boxes, and are used to tie several wires together. An example usage is when one switch controls multiple outlets. The junction box also protects the cables and allows easier access in future. Junction boxes are also used at certain intervals in long conduits. See Figure 3.4.3 (b). While switch boxes and in some cases outlet boxes should meet accessibility standards, junction boxes typically do not. However, junction boxes should be easily accessible to electricians. Typically, in case of a junction box flushed with the surface of a wall or a ceiling, a cover plate is used on top of it for easy access. In case of multiple decorative ceilings, the locations of junction boxes should be coordinated with an electrical engineer. Switch box

Outlet box

Chapter 3 : Building Services

Right : Figure 3.4.3 Shows outlet box, switch box, and junction box. CREDIT: (a) http://www.amadeuselectric.com/uimages/ iStock_000006756593XSmall.jpg (b) www.rightengineering.in/F8203/ junction_boxes.html‎

(a) Outlet box and Switch box

(b) Junction box


3.4.4 Grounding and Circuit Interrupters

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All electrical systems should be grounded by the use of a third wire. This wire redirects live currents into the ground to prevent electric shocks to humans in case of a short circuit. Hence, grounding is extremely important from a life safety point of view. Since grounding is usually not fully effective, circuit interrupters should be used as well. Two major types of circuit interrupters are described below.

Ground Fault Circuit Interrupters (GFCI): A GFCI is a special device that disconnects the power to the circuit or appliance even if small current leaks occur, preventing major shocks. This is installed either in the electrical panel or in the electrical outlet. GFCIs are used typically when water is present, because contact with water makes it easier for electricity to flow, resulting in shocks even in presence of grounding. Examples of such areas include restrooms, bathrooms, kitchens, break rooms, bars, laundry rooms, pools, and spas.

Arc Fault Circuit Interrupters (AFCI): AFCI works by detecting arcs instead of current leaks. Arcs are produced typically when an electrical wire discharges unwanted current across its insulation. AFCIs are typically used in residential occupancies, especially in sleeping rooms. They are used for receptacles, light and fan fixtures, and smoke detectors. The arc activates the device, which disconnects power to the circuit.

Note : Arcs produce much heat, which can potentially melt metal or ignite combustible materials in the surrounding. Hence, outlets where arcs may be expected should have fire protection.

3.4.5 Light Fixtures Light fixtures (also known as luminaires) have special requirements based on their type and where they are installed. Two typical specifications control the weight of the fixture and the wattage of the lamp used. â&#x20AC;˘ Fixtures more than 50 pounds (23 kgs) need additional support independent of the outlet box (or need special outlet box designed to support heavy loads).[1] Examples of such heavy fixtures include ceiling fans and larger pendants or chandeliers. â&#x20AC;˘ Wattage of the lamp is restricted to prevent overheating and damage to wiring as a result.

Fire Protection and Ventilation Requirements:

Light Fixtures in Shower Areas: Such fixtures have special requirements to prevent shocks to a person standing in water. If the fixture is not surface-mounted and recessed fixtures, its hanging parts should not be within 8 feet (2.5 m) above the top of the bathtub rim, within 8 feet (2.5 m) above a shower threshold, or up to 3 feet (900 mm) within the plumbing fixture.

Note : If the shower has no threshold, the measurement is taken from the floor.

Electrical Systems

The mechanical part of fixtures installed in (typically recessed in) rated ceiling or wall assemblies should either be rated itself or should be enclosed in a box that is rated. In case of non-rated wall/ceiling, noncombustible material should be put between the fixture and the wall/ceiling finish. In all cases, it should be cautioned that the fixtures installed do not interrupt the desired and planned air circulation routes.


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3.4.6 Special Electrical Systems Many building codes (e.g., the NFPA Life Safety Code[2] and other NFPA codes[3,4]) have specifications for two special electrical systems: emergency electrical system and standby power system. These specifications depend on the construction type and the occupancy type of the building. While an electrical engineer typically designs these systems, the interior designer should be able to understand them and be aware of them because they affect the selection of fixtures and other interior elements.

Emergency Electrical Systems Note : Emergency electrical system may also be used to provide power to life-support equipment in hospitals.

Chapter 3 : Building Services

Note : The same electrical system may be used to serve as both standby and emergency electrical systems. Although, standby power systems have much weaker requirement for the response time (about 1 minute) compared to emergency electrical systems (about 1 second) after the normal power fails.

An emergency electrical system is required in most buildings to maintain certain illumination (e.g., emergency lighting) at all times. It serves as a backup to normal electrical system with the main purpose of allowing safe evacuation of occupants in case of emergency. It should have sufficient power to illuminate means of egress lighting, exit signs, automatic door locks, fire protection systems, and other emergency equipment. See Section 3.2.5 for egress signage and illumination.

Standby Power Systems A standby power system also acts as a backup to normal electrical system in case of emergency. But it is not used to facilitate egress, but rather to power other building systems such as the mechanical system, fire pumps, general lighting, communication systems, elevators, etc. It is typically used in high-rise buildings and Assembly, Institutional, and Hazardous occupancies. It should be used especially when the building has a smoke control system which requires power in case of emergency.

End Notes 1. NFPA 70: National Electrical Code. National Fire Protection Association, 2012. 2. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. 3. NFPA 110: Standard For Emergency and Standby Power Systems. National Fire Protection Association, 2013. 4. NFPA 111: Standard on Stored Electrical Energy Emergency and Standby Power Systems. National Fire Protection Association. 2013.


4

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Interior Environment Contrary to popular belief, aesthetic enhancement and wear-and-tear protection are not the only functions of interior materials and finishes. Various characteristics of these materials and finishes determine how quickly they burn, how fast fire spreads across their surface, or if they generate toxic smoke upon burning. These characteristics matter considerably for fire protection. Hence, the first part of this chapter focuses on the specifications that aim to minimize the hazards associated with interior materials and finishes. At the same time, the purpose of signage is also not solely to provide comfort to the occupants; it becomes a life-saver in emergency situations. While egress signage (discussed in Chapter 3.2.5) facilitates occupant evacuation, outdoor display signboards may present hazard to the pedestrians and the drivers on the road near the building. The level of hazard depends on various parameters of the signs such as type, location, dimensions, illumination, materials used, etc. The second part of this chapter presents safety-critical specifications for outdoor display signboards.

In This Chapter, 4.1 Interior Materials and Finishes

..... 90

4.2 Signage Design

..... 97


90

4.1 Interior Materials and Finishes

In This Part, 4.1.1 Types of Furnishings and Finishes 4.1.2 Classification of Interior Materials Interior wall and Ceiling Finishes

Interior Floor Finishes

Non-Rated Finishes

4.1.3 Code Requirements for Materials Plastics

Safety Glass Textile Wood

Chapter 4 : Interior Environment

4.1.4 Additional Specifications

The design and specification of furnishings and finishes is one of the most important tasks for an interior designer. The codes limit the use of interior finish materials based on their flammability, the occupancy group, and the areas of the building in which they are used. Materials and finishes are classified according to their flame spread and smoke development characteristics. Ratings for finishes are different than those for building materials and assemblies. The knowledge of these ratings and their application-specific requirements helps an interior designer evaluate the choices made. While NBC[1] has minimal specifications regarding interior materials and finishes, other codes such as IBC[2], NFPA 5000[3], and NFPA Life Safety Code (NFPA 101)[4] specify detailed specifications in this case. Most of the concepts in this chapter are derived from the latter codes.


4.1.1 TYPES OF FURNISHINGS AND FINISHES

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While furnishings include furniture, fittings, and other decorative accessories, such as curtains and carpets, finishes are the products that are applied on top of the materials. Most interior finishes refer to the exposed surfaces of walls, ceilings, and floors, including partitions, wainscoting, paneling, floor covering, etc. These finishes may be applied structurally or for decoration, acoustical correction, surface insulation, or similar purposes. (Trims such as baseboards, window and door casings, or similar materials used in fixed applications are not included.) There are mainly seven different types of interior furnishings and finishes. 1. Ceiling finishes. Refers to the exposed interior surfaces of ceilings. This includes suspended ceiling grids, as well as coverings applied to fixed and movable ceilings, soffits, beams, space frames, etc. 2. Wall finishes. Refers to the exposed interior surfaces of walls. This includes coverings applied to fixed or movable walls, partitions, columns, etc. Examples of such coverings are paint, vinyl and paper/textile wallcovering, wood paneling, and applied acoustical finishes. 3. Floor finishes. Refers to the exposed interior surfaces of floors. This includes coverings applied to finished or unfinished floors, stairs (including risers), ramps, etc. Examples of such coverings are hardwood, ceramic tile, vinyl, linoleum, carpets, and rug.

5. Trim and decorative materials. Refers to the exposed decorative elements or protective materials attached to the interior wall or ceiling. This includes decorative moldings, wainscoting, baseboards, chair rails, picture rails, handrails, door and window moldings, etc. 6. Furnishing finishes. Refers to the exposed finishes applied to goods furniture, systems furniture, wood veneers, and laminates, etc. In this category, non-exposed finishes such as the foam in the seating, liners in the drapery, etc. are also included. 7. Furniture. Refers to whole pieces of furniture rather than separate parts and finishes. This category usually includes upholstered products such as seating and panel systems, mattresses (including its fabric, padding, coils, and other bedding assemblies), etc.

Interior Materials and Finishes > Types of Furnishings and Finishes

4. Window treatments. Refers to the decorative elements that control the amount of light from a window area. These include draperies, liners, blinds, shutters, curtains, etc. These elements can be made of textiles, wood, vinyl, and other similar materials.


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4.1.2 CLASSIFICATION OF INTERIOR MATERIALS The specifications on materials used in interior finishes of walls, ceilings, and floors attempt to ensure that the exits are free of fire and smoke for safety and visibility. Therefore, the specifications become stricter as one moves toward an exit. These specifications recommend various tests to measure certain characteristics of the materials related to fire and smoke, and classify the materials accordingly. The tests required to measure such characteristics are different for materials used in wall and ceiling finishes and those used in floor finishes. Due to this, the categories are defined differently in both cases â&#x20AC;&#x201D; Class A, B, and C for materials in wall and ceiling finishes, and Class I and II for materials in floor finishes. Both types of finishes are described next.

Interior Wall and Ceiling Finishes

Note : Note that there is no direct relationship between FSI and SDI. A material can have high FSI but low SDI, or it can also have low FSI but very high SDI.

Materials for interior wall and ceiling finishes are rated via a standard test called the Steiner Tunnel Test, which uses two metrics: the flame spread index (FSI), and the smoke development index (SDI). The flame spread index (FSI) indicates how quickly fire spreads across the surface of a material. Lower FSI is better, because it indicates slower spread of fire, which would allow more time to evacuate the building. Similarly, smoke development index (SDI) indicates the concentration of smoke generated when the material is under fire. Once again, lower SDI is better because thick smoke reduces visibility and therefore an occupantâ&#x20AC;&#x2122;s ability to easily find the means of egress. Underwriters Laboratories determined that for reasonable visibility, the smoke development index should not be greater than 450. This standard has been adopted by various codes[2,3,4] for all materials. Thus, the codes classify the materials based on their FSI, as shown in Table 4.1.2 A.

Right : Table 4.1.2 A Describes the classification of materials in interior wall and ceiling finishes.

Group Class A Class B Class C

Flame Spread Index (FSI) 0-25 26-75 76-200

Smoke Development Index (SDI) 0-450 0-450 0-450

Note: Class A is the most strict, whereas Class C is the least strict.

Chapter 4 : Interior Environment

Interior Floor Finishes Materials for interior floor finishes are rated via the Radiant Panel Test, which determines the intensity required for a flame to sustain on a floor covering. This is measured using the critical radiant flux (CRF) (unit: watts per sq. cm.) of the material. Higher CRF is better because it indicates that less intense fires cannot sustain on the floor covering. Accordingly, the materials are classified in two categories. Class I. CRF of at least 0.45 watts per sq. cm. Class II. CRF of at least 0.22 watts per sq. cm.


93 Occupancy

Interior Finish Classification Limitations Exits Exit Access Corridors

Other Spaces

Assembly New, ≤ 300 occupant load New, > 300 occupant load Existing, ≤ 300 occupant load Existing, > 300 occupant load

A, I or II

A or B, I or II

A

A or B

A, B, or C A or B A, B, or C A or B

Business New Existing

A or B, I or II

A or B

A, B, or C

A or B, I or II

A or B

A or B

A or B

A or B

Ceilings—A or B; Walls—A, B, or C

A, B, or C

A, B, or C

A, B, or C

A or B

Mercantile New Existing, Class A or Class B Stores Existing, Class C Stores

Notes: 1. See above for the definitions of Class A, B, and C materials in interior wall and ceiling finishes, and Class I and II materials in interior floor finishes. 2. When automatic sprinklers are installed, Class C material can be used in place of Class B specification, and Class B material can be used in place of Class A specification. Similarly, Class II material can be used in place of Class I specification, and no critical radiant flux (CRF) rating is required for a material in place of Class II specification.

Non-Rated Finishes If a finish material is non-rated (i.e. it does not pass the required tests), an alternative is to apply fire-retardant coatings to it. When walls or ceilings are required to have a fire-resistance rating or to be noncombustible, finishes should be applied directly to the construction element or to furring strips not greater than 1¾ in. (44 mm) thick, which in turn are applied directly to the construction element. If the finishes project more than this amount or are suspended from the structure above, then they must be a Class A material or have sprinklers on both sides.

Material Classification and Use in NBC: Table 4.1.2 C provides the classification of materials in NBC[5] based on the rate of spread of flame across their surface, which is similarly to the classification by IBC. See good practices [4(14)] and [4(15)] for further details.

Above : Table 4.1.2 B Describes what materials may be used in various occupancy types under different conditions. Adapted from “NFPA 101: Life Safety Code”, National Fire Protection Association, 2012. p. 394.

Interior Materials and Finishes > Classification of Interior Materials

Table 4.1.2 B describes which of the abovementioned material classes should be used in what places. The specification clearly depends on the occupancy classification, and sometimes on the occupant load as well. Additionally, as mentioned previously, the specification becomes stricter along the egress path, being the strictest near the exit. (If spaces such as reception areas in Business occupancies are not separated from the corridor, they should be considered part of the exit access corridor. )


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Right : Table 4.1.2 C Shows the classification of interior materials as per NBC.

Class Class 1 Class 2 Class 3 Class 4

Surfaces Very low flame spread Low flame spread Medium flame spread Rapid flame spread

The following is suggested for use of materials in different classes. • Class 1. These may be used in any situation. • Class 2. May be used in any situation, except on walls, building facade, staircases, and corridors.

Note : Some Class 4 materials contain bitumen, and thus emit dense smoke on burning. These should not be used in kitchens, corridors, and staircases, and also not for construction of ceilings of airconditioned buildings where plenum is used for return air.

• Class 3. May be used only in living rooms and bedrooms (that are not on the roof), and only as a lining to solid walls and partitions. Should not be used on staircases, corridors, or building facade. • Class 4. (Includes untreated wood fibreboards). May be used with due fire retardant treatment as ceiling lining, provided the height of the ceiling is at least 2.4 m. Should not be used in kitchens, corridors, and staircases. When frames, walls, partitions, or floors are lined with combustible materials, surfaces on both sides should meet the abovementioned specifications, otherwise the fire may start and rapidly spread within the concealed cavity. The occupants may not even be able to observe this, but it may hamper their safe evacuation.

4.1.3 CODE specifications FOR MATERIALS Plastics Cellular or foam plastic materials should not be used as wall or ceiling finishes except when they satisfy the 10 percent rule (explained later in this chapter). In case they are used, they should be of a certain thickness and density, and should be checked on-site using practical tests. Foam plastics that do not meet the abovementioned specifications may be used if it is covered by a noncombustible material that acts as a thermal barrier. Pyroxylin plastics (such as imitation leather) should not be used in Assembly occupancies.

Chapter 4 : Interior Environment

Light-transmitting plastics include items such as Plexiglas and resin panels that can be used in a variety of applications, such as wall panels, light-diffusing panels, and signage. Sometimes, they have fabrics sandwiched between two layers. The codes may have certain specifications for such plastics regarding its size and fastening as well as sprinkler specifications. Finally, the use of plastics may also affect the location of sprinkler heads. For example, additional sprinkler heads are often required where large lighttransmitting plastic panels are used.


95 FLAME-RETARDANT TREATMENTS Polymers and salines are themselves flame-resistant finishes which are applied directly to the fabric. However, if a non-flame-resistant finish is already applied, it can be treated using flame-retardant treatments to help comply with the code specifications. Such treatments involve adding a fire-retardant coating to the fabric. They can sometimes alter the finish or the piece of furniture the finish may be applied to. Applying flame-retardant treatments may cause problems similar to those mentioned above for flame-resistant finishes. Additionally, fire-retardant coatings may also give off toxic fumes, especially in the presence of fire.

Safety glass Apart from fire-rated glazing, glass has several other uses in interior applications as well, e.g., a glass panel in a stair railing, a shower enclosure, a decorative glass sign or feature, a table top, etc. Based on the location, thickness, and size of the glass, the codes may require the glazing to pass certain tests to meet safety glass specifications. For example, tempered glass may often be required.

Wood When wood is used as an interior finish, it may need to be treated. A classical example is wood veneer used as a wallcovering in a commercial space. Fire resistance properties of wood depends on its species and its thickness. Typically, thinner woods and veneers have worse ratings than thicker ones. However, certain types of intumescent paints and coatings may be applied to the wood to increase its rating.

Note : Some woods when treated with a fire retardant would be Class A flame-spread-rated. Most untreated wood either have a Class C flame spread rating or no rating at all.

Textile

A polymer finish is applied through an immersion and heat-setting process. Shrinkage can occur as a result of such a treatment. In some fabrics, there may be a noticeable change in color or stiffness. Although they are quite durable, most polymer flame-resistant treatments eventually wash out if the fabric is dry cleaned. A saline finish is less expensive, but is not as durable as polymer solutions. The salt solution has a corrosive effect on metals, e.g., upholstery tacks and staples, and may leach out. Flame-resistant backings provide far more protection against the spread of fire than flame-resistant treatments. Aramid fabrics are laminated to the back of upholstery fabric. Lamination reduces the amount of labor involved in applying the barrier fabric between the seat cushion and the finish fabric. Instead of being upholstered twice, first with the aramid and then with the upholstery fabric, the seat is upholstered only once with the laminated fabric. When textiles are used as wallcoverings, they should have a Class A flame spread index and be protected by automatic sprinklers. When used to limit the spread of fire, sprinklers in this instance only need to be installed where the textile wallcoverings are used.

Note : Fabrics have varying degrees of resistance to heat and flame. In general, lighter, more open fabrics will burn more freely than denser material. Finishing also plays a crucial role in the resistance of a fabric to fire; its effectiveness may decrease over the time, and cleaning processes may reduce the amount of fire resistance.

Interior Materials and Finishes > Code Requirements for Materials

In reference to the codes, textiles include materials having woven or nonwoven, napped, tufted, looped, or a similar surface. To meet the specifications set by the building and fire codes, fabrics sometimes need to be treated with flame-resistant finishes. There are two types of flame-resistant finishes: polymers and salines. The type of fabric determines which process is appropriate for application.


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4.1.4 Additional SPECIFICATIONS The codes also have additional specifications regarding interior furnishings and finishes, some of which are summarized below. • The 10-percent rule: When trims and decorative finishes occupy only up to 10 percent of the wall and ceiling, materials with lower rating than the required may be used. For example, trims usually require Class C rating, but if it does not exceed 10 percent, combustible materials may be allowed. However, these finishes should be evenly distributed, and should not be concentrated in a specific area. Noncombustible trims and decorative materials are not limited. Some occupancies, such as certain Assembly types, may allow a higher percentage in this rule.

Fuel Load The amount of flammable material that surrounds a fire is referred to as the fuel load. Note : Vinyl wallcoverings are regulated in all thicknesses because of their special burning characteristics and the tendency to create high smoke density.

• Thickness rule: A wall or ceiling covering with less than 0.036 inch (0.90 mm) thickness applied to a noncombustible material (e.g., gypsum board, brick, and concrete) does not significantly contribute to the fuel load, and therefore does not need to be rated. Examples of such thin coverings include thermally thin finishes such as paint and most wallpapers (not vinyl wallcoverings). This rule does not apply when finishes are applied on top of each other. If the covering is less than or equal to ¼ in. (6 mm) thick, it should be applied directly against a noncombustible backing unless it is a Class A material. • Furring strips: When interior finishes (such as wood flooring or wall paneling) are applied to furring strips instead of directly to the noncombustible building materials, the furring strips should be at most 1.75 in. (44 mm) thick. Further, the intervening spaces between the strips should be filled with a fire-rated material or be fireblocked at intervals of not more than 8 feet (2438 mm). This is to reduce the chance of fire spread between the finish and the construction assembly behind it. • Means of egress: All exits and paths of travel to and from the exits should not have any furnishing, decorations, or other objects, including draperies or mirrors on/near exit doors. Also, no item should draw attention away from an exit sign.

Chapter 4 : Interior Environment

Generally, occupancies where the occupants are large in number and less mobile (possibly due to imposed restrictions), e.g., Assembly occupancies, often have stricter specifications than occupancies with fewer fully mobile occupants, e.g., Storage occupancies. Ultimately, the onus is on the designer to verify that all materials used meet the specifications.

End Notes 1. 2. 3. 4. 5.

The National Building Code of India. Bureau of Indian Standards, 2005. The International Building Code. International Code Council, 2012. NFPA 5000: Building Construction and Safety Code. National Fire Protection Association, 2012. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. The National Building Code of India. Bureau of Indian Standards, 2005. Part 4, pp. 24-25.


4.2 Signage Design

97

In This Part, 4.2.1 Importance of Outdoor Display Signboards 4.2.2 Unsafe Signs 4.2.2.1 Location

4.2.2.2 Illumination 4.2.2.3 Materials

4.2.3 Types of Signs 4.2.3.1 Electric Signs and Animated Devices

4.2.3.2 Ground Signs 4.2.3.3 Roof Signs 4.2.3.4 Wall Signs 4.2.3.5 Projecting Signs 4.2.3.6 Marquee Signs

The connection of signage with building and life safety is twofold. Signs used in the interior of a building such as egress signage facilitate smooth and safe egress process for the occupants, and therefore contribute towards their life safety. These are extensively covered in Chapter 3.2. On the other hand signs used on the exterior of a building, may cause danger to pedestrians by falling on them, to drivers by causing distraction, or in some cases, to the occupants of the building as well by hampering their evacuation (as explained in this section). Such outdoor display structures are therefore also important for building and life safety. Common examples include advertising or brand name signs which are put up on building facades or display structure on the shop front.


98

4.2.1 IMPORTANCE OF Outdoor display Signboards The importance of outdoor display signboards from a building and life safety perspective stems from three potential dangers caused. 1. Danger to the pedestrians. If the length, height, and weight of a sign-

board are not chosen adequately, the signboard or some parts of it may fall by accident or due to other causes, posing a danger to the pedestrians passing by.

2. Danger to the drivers on the road. If the location of the signboard is

not chosen carefully, the signboard may obstruct or interfere with the visibility of the approaching, merging, or intersecting traffic. Further, signs that do not use appropriate colours and texts, e.g., signs that use colours from the standard legal traffic signs or use words such as ‘STOP’, may cause confusion among the riders on the street. Such obstructions and confusions may in turn cause fatal accidents.

3. Danger to the occupants. If the placement of the signs is not appropri-

ate, e.g., signs exhibited within the window of a building, may cut off light or ventilation in the building.

Note that the abovementioned considerations do not only concern the safety of the occupants, but also the safety of the general public. In this sense, these are not only active but also passive safety considerations, which are in line with the central idea of this thesis that the decisions made by one individual should not adversely affect the welfare of the others. While many codes such as IBC[1] and NFPA Life Safety Code[2] do not focus on outdoor display signboards, NBC[3] gives specific emphasis by requiring a permit to put up any such signs.

Chapter 4 : Interior Environment

“Part 10, §3.1.1[4]: No sign shall be erected, altered or maintained without first obtaining a permit for the same from the Authority and shall be subjected to [a variety of] conditions. In fact, NBC[5] provides a form which requires critical information regarding the sign, which should be filled by the applicant in order to obtain a permit or license. It also requires that afterwards the signs should be maintained in a good condition, e.g., any non-galvanized materials or materials that are not corrosion-resistive should be painted over whenever necessary. The chapter proceeds by first describing certain scenarios in which the outdoor display signboards can be considered unsafe due to one or more of the three dangers described above. Then, various specific types of signs and their corresponding specifications are described.

4.2.2 UNSAFE SIGNS This section describes a variety of situations in which the outdoor display signboards may be considered unsafe and what the safe practices are, as per NBC.[6] Three important parameters that are critical to safe practices of signage are:


• location of the signs, • illumination of the signs, and • the materials used.

99

In the following, the specifications corresponding to each parameter are described.

4.2.2.1 Location The location of the sign should be sensitive with respect to: 1. the building and its elements, to ensure the safety of the occupants, 2. the exterior of the building, to ensure the safety of general public. NBC suggests the following when choosing the location of signs. • No sign should be placed so that it obstructs: • fire escape, • doors or windows, • any openings used as a means of egress or for firefighting purposes, or • pedestrian movement. • No sign should be an obstacle when using hydrants or other firefighting equipment.

• No sign should be placed at or within 100 m of any road junction, bridge or railway crossing, or any other crossing. This specification may be reduced to 50 m in urban areas. • No sign should be an obstacle in the path of any pedestrians, or hinder their visibility at the crossings. • No sign should be placed within 10 m of the edge of a carriageway, and the area of the advertisement should not be more than 0.3 m2 for every metre of setback from the carriageway. • No sign should be placed less than two storeys or 6 m above the footpath (whichever is greater).

4.2.2.2 Illumination In general, the illumination of signs should be safe, and should not distract or otherwise cause problems for the drivers or the pedestrians on the street beyond a reasonable level. Particular concerns are given below. • Signs should only be illuminated using electrical means, as prescribed in Section 2 (Electrical and Allied Installations) of Part 8 (Building Services) of NBC.[7] Open sparks or flames should never be used, not just for illumination, but also for display purposes.

Note : The safe distance of 100 m is calculated as follows. Assuming the speed of the vehicle to be 50 km/h and that the influence of an advertisement board lasts for 3 seconds, the driver would drive 40 m under the influence. Afterwards, applying brakes would require another 60 m of safe stopping distance.

Signage Design > Unsafe Signs

• No sign should obscure or hinder the interpretation of any other signboard, signal, or any other device erected by the authorities. Such hindrance may be caused by similar colour or shape, similar words as those used in traffic signs, or obstructing locations. In particular, signs should not be placed within 50 m (measured along the road) of any sign board erected for traffic regulation by the authorities.


100

• The illumination should not be flashing or intermittent, and should not use moving lights. Its intensity should be limited so as to not cause glare, vision impairment, or other problems for drivers or pedestrians. • The illumination should not be in such a way as to reduce the effectiveness of traffic signals, signs, or other such devices.

4.2.2.3 Materials Various specifications restrict the use of certain materials such as combustible materials and glass within outdoor display signboards. Combustible Materials • Wood, plastic, or other combustible materials should only be used for mouldings, cappings, nailing blocks, and purely ornamental features of signs. • Sign facings should usually be made of noncombustible materials. However, if the area of each face is at most 10 m2, approved combustible materials may be used. Any electric wiring is entirely enclosed in metal conduit, and this should be at least 5 cm away from the facing material. Glass • All glass used in advertising signs, other than glass tubing used in gas discharge or similar signs, should be safety glass (see good practice [102(2)]) with at least 3 mm thickness. • Glass panels used should not be larger than 6 m2 in area, with each panel securely fixed in the body of the sign independently of all other panels. • Another important consideration is to protect glass signs from the possibility of damage by falling objects. This may be achieved, for example, by providing suitable protecting metal canopies. • In general, use of glass is discouraged and should be avoided wherever possible for signs placed overhead.

4.2.3 TYPES OF SIGNS The specifications described above are safety-related considerations that apply to all types signage. Additionally, specific signage types require additional considerations regarding the materials used, the dimensions, etc. Below, a few major types of signage are described along with the specifications critical for building and life safety.

Chapter 4 : Interior Environment

4.2.3.1 Electric Signs and Animated Devices • Material. Electric signs should be made of noncombustible material. • Signs with moving sections or ornaments. These should have a fail-safe provision, so that if the section or ornament is released and falls, the fail-safe mechanism should be able to support its full dead weight. This mechanism should also prevent the moving section or ornament from shifting its center of gravity by more than 450 mm. The fail-safe device should be in addition to the mechanism that operates the moving section or ornament, and its housing.


Left : Figure 4.2.3.1

101

Shows electric signs. CREDIT: http://i.dailymail.co.uk/i/ pix/2014/02/19/article2562966-1884AF6900000578195_634x422.jpg

4.2.3.2 Ground Signs • Material. Ground signs that exceed 6 m in height (including the frames, supports, and braces) should use noncombustible materials. Possible use of combustible materials is described in Section 4.2.2.3. • Dimensions. The height of ground signs should be at most 9 m above the ground. Lighting reflectors may extend beyond the top or face of the sign. • Location. Ground signs should not obstruct access to or egress from any building. They should not be placed beyond the boundary of the building that distinguishes it from the adjoining street. The bottom of the ground sign should be at least 0.6 m above the ground. The intervening space may be filled with open lattice work or platform decorative trim. • Supports and Anchorage. Ground signs should be anchored to the ground or be firmly supported otherwise. Supports and anchors should use treated timber (see good practice [10-2(3)]), metal treated for corrosion resistance, masonry, or concrete.

Shows ground signs. CREDIT: http://2.bp.blogspot.com/SHCylU4X6M0/US6DHWDM17I/ AAAAAAAALtw/fAqn1tbZmQQ/ s1600/squaresigns.jpg

Signage Design > Unsafe Signs > Types of Sign

Left : Figure 4.2.3.2


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4.2.3.3 Roof Signs • Material. Roof signs and their frames, supports, and braces should be constructed using noncombustible material. If combustible materials are used (as per Section 4.2.2.3), all wiring and tubing should be insulated. All metallic parts should be provided electric grounding, • Dimensions. Table 4.2.3.3 describes how high a roof sign can be, depending on the height of the building itself.

Right : Table 4.2.3.3

Height of Building

Maximum Height of Roof Sign

Describes the maximum height of roof sign depending on the height of the building. Adapted from “The National Building Code of India” BIS, 2005. Part 10, p. 19.

<= 4 storeys or 18 m

2m

5-8 storeys or 18-36 m

3m

> 8 storeys or 36 m

5m

Note: While calculating the height of the sign, multiple signs either placed on top of each other or on planes at different levels should be considered as one sign (even if they belong to different owners).

• Location. Roof signs should not block access of any parts of the roof from any other parts. Roof signs should only be used when the roof of the building is constructed entirely using noncombustible materials. • Supports and Anchorage. Roof signs should be thoroughly secured and anchored to the building. Loads should be safely distributed to the structural members of the building. • Projection. Roof signs should not extend beyond the roof (or the existing building boundary) in any direction.

Right : Figure 4.2.3.3 Shows roof signs. CREDIT: http://www.mouse-ps.com/img/ thumbs/resize_597x282_9c0b3aaa 80aaf6e280b6e115e21c8b61_1_2_ Roof_signs.jpg

4.2.3.4 Wall Signs

Chapter 4 : Interior Environment

• Material. Wall signs with more than 4 m2 area should be constructed using noncombustible materials; exceptions are described in Section 4.2.2.3. • Dimensions. The area of wall signs should be at most 20 m2 for every 15 m of the building frontage to the street that the wall sign faces, and it should not exceed 25 percent of the side wall area visible from the street. A wall sign only containing the name of a theatre or building should not be larger than 200 m2. Wall signs directly facing the road should not be larger than 30 m2. • Supports and Attachment. Wall signs should be thoroughly attached to the walls. Unless the sign is attached to a wooden wall, wooden blocks or anchorage with wood used in connection with screws, staples or nails are not considered sufficient.


103

• Projection. Wall signs should not extend beyond the wall in any direction. If pedestrians are expected to pass along a wall, the wall sign should not project more than 7.5 cm in first 2.5 m above the ground.

Left : Figure 4.2.3.4 Shows wall signs. CREDIT: http://www.carricksigns.co.uk/samples/shop_signs_tray1.jpg

4.2.3.5 Projecting Signs • Material. Projecting signs as well as their support and framework should be constructed entirely using noncombustible materials.

Height of Building <= 4 storeys or 18 m 5-8 storeys or 18-36 m > 8 storeys or 36 m

Maximum Height of Projecting Sign 9m 12 m 15 m

Left : Table 4.2.3.5 Describes the maximum height of projecting sign depending on the height of the building. Adapted from “The National Building Code of India” BIS, 2005. Part 10, p. 20.

Left : Figure 4.2.3.5 Shows projecting signs. CREDIT: http://ulrichsigns.com/portfolio/ Old-City-Hall-1.jpg

Signage Design > Unsafe Signs > Types of Sign

• Dimensions. Table 4.2.3.5 describes how high a projecting sign can be, depending on the height of the building itself.


104

• Projection. Projecting signs (together with their supporting framework) should not project more than 2 m beyond the building, and not beyond the plot line facing the street. For projections into the street, the first 2.5 m above the road level should not have any projection. Projecting signs should not extend beyond the eaves of the roof or above the part of the building face it may be attached to. • Supports and Attachment. Every projecting sign should be securely attached to the building so that movement in any direction is prevented by corrosion-resistant metal brackets, rods, anchors, supports, chains or wire ropes. Moreover, even half of the number of fixing devices used should be able to support the sign under all circumstances. Staples or nails should not be used to secure any projecting sign to any building.

4.2.3.6 Marquee Signs • Materials. Marquee signs should be constructed entirely of metal or other approved noncombustible materials. • Dimensions. Such signs should have at most 2 m height. They should not extend below the fascia of the marquee, and should be at least 2.5 m above the footpath. When they extend the full length, they should not project beyond the ends of the marquee.

Right : Figure 4.2.3.6

Chapter 4 : Interior Environment

Shows marquee signs. CREDIT: http://cfnewsads.thomasnet.com/ images/large/450/450632.jpg

End Notes 1. 2. 3. 4. 5. 6. 7.

The International Building Code. International Code Council, 2012. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. The National Building Code of India. Bureau of Indian Standards, 2005. Ibid. Part 10, p. 6. Ibid. Part 10, p. 23. Ibid. Part 10, pp. 9-18. Ibid. Part 8, Section 2.


5

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Case Study While the main body of the thesis focuses on the concepts of interior design that are critical to building and life safety, case studies are presented in this chapter that focus on observing the corresponding details in a commercial built environment. Note that the purpose of the case studies is not to evaluate the safety of any given place, but solely to illustrate which safety-critical details can be observed, where they can be observed, and how the interdependency between such details can be analyzed. The two case studies shown below have been chosen based on three main criteria. First, the mall is chosen to illustrate special code specifications that apply to assembly occupancy, and the office (business occupancy) is chosen because it is a very common type of space. Second, the two case studies present a huge variation in the scale. Third, the office is part of a building (thus, its interior excludes many building elements), whereas the mall is itself an entire building. Hence, some observations in the analysis of the mall may not be part of the analysis of the office.

In This Chapter, â&#x20AC;˘ Office: Sambhav Infrastructure Pvt. Ltd., Ahemedabad

..... 106

â&#x20AC;˘ Mall: Gulmohar Park Mall, Ahmedabad

..... 116


106

Case Study Methodology Based on the research presented in this thesis, various checklists are prepared (given in Appendix C) that list all the observations for which the codes mention safety-related specifications. Usually, most of the decisions are taken in the design stage, but a lot of them later get concealed during the execution. Hence, only the observations that would be tangible in a built environment are described. Such observations may still provide a basic idea of the safety measures used in the place.

Please Note ... 1. In the checklist, the appropriate choices are ticked, and wherever required, data is provided by making the relevant observations. 2. In some parts of the checklist (‘fire resistance’, and ‘furnishings and finishes’), only a table containing a list of the relevant elements is given. Among these elements, the ones present in the space (or in the building) are ticked in the table itself. Additionally, they are also shown in plans/sections. 3. Although the space considered in this case study (the office) is part of a building, observations are also made for the relevant parts of the building outside the office. This is because such parts (e.g., certain elements of means of egress) affect the safety of the occupants in the office as well. However, some of the data may not be available for such elements. *If an entire building were to be considered, all its parts would need to be observed.

4. Where the specifications do not match the provisions (data required and data given) in the space, safety issues arise, which are highlighted in the checklist. 5. The checklists are accompanied with analyses that explain connections between certain decisions and the safety issues.

Office: Sambhav Infrastructure Pvt. Ltd.

601, Pinnacle, Corporate Road, Prahaladnagar Garden, S.G.Road, Ahmedabad, Gujarat. Owner : Mr. Mihir Shah


Left : Figure 5.2

Shows the site plan in which the location of the office is highlighted. CREDIT: http://www.goyalco.com/ commercial/pinnacle/ NOTE: The site plan shown here (adapted from builder’s website) is not up-to-date and just for the reference; the actual plan with a small modification is given on Page 109.

ADMIN CABIN 11'-2" X 10'-0" 115 SQFT.

ENTRY MARKETING CABIN - 1 8'-3" X 13'-0" 110 SQFT.

ENTRY

Figure 5.1 PLAN OF THE OFFICE - “ SAMBHAV INFRASTRUCTURE PVT. LTD. ” (2013)

Right : Figure 5.3 Shows various observation checklists prepared based on the research presented in this thesis. The checklists continue on later pages, and are accompanied with the corresponding analysis.

107

SCALE 1 : 5


108

Exit Separation Analysis: The distance between the two most distant points in the floor plan is shown in Figure 5.4 as â&#x20AC;&#x2DC;Dâ&#x20AC;&#x2122;. The distance between the two exit staircases is almost 1/3 D. Thus, the floor plan meets the 1/3 diagonal rule instead of the 1/2 diagonal rule. However, this is only allowed when sprinklers are present. As can be seen from Figure 5.4 D, this is not the case here.


Left : Figure 5.4

109

Shows the means of egress. A) From the office interior to the office main door, B) From the office main door to the building main door. C) Existence of dead-end corridor. D) Absence of sprinkler systems. (1) through (7) show various components of the egress path.

ADMIN CABIN 11'-2" X 10'-0" 115 SQFT.

Modified and re-drawn from an existing drawing. Placement of Fire extinguisher cupboard in plan. Details are explained on p. 113.

(3a)

MARKETING CABIN - 1 8'-3" X 13'-0" 110 SQFT.

ExIT

(4)

1/3 D D (86 m approx)

(6)

(3b) (1)

(7)

(5) ATRIUM

ENTRY

A)

(2)

PLAN OF THE OFFICE - “ SAMBHAV INFRASTRUCTURE PVT. LTD. ” (2013)

SCALE 1 : 5

B)

FLOOR PLAN OF THE OFFICE BUILDING - “ PINNACLE ”

SCALE 1 : 20

Means of Egress Components: Components (1) through (7) shown in Figure 5.4 are components of the egress sequence on the opposite page: (1) office corridor, (2) office main door, (3) floor corridor, (4) exit staircase, (5) foyer, (6) building exit door, and (7) exit court. Travel Distance Analysis: Travel distance within the office = length of (1) = 21 m. Travel distance outside the office = length of (3a) + length of (3b) = 34 m. Thus, the maximum travel distance (7b in the checklist) = 21+34 = 55 m. This distance significantly exceeds the maximum travel distance allowed (30 m, 7a in the checklist), which is a safety issue. Also, there exists a dead-end corridor (see Figure 5.4 C), and its length (7d in the checklist, also see Figure 5.5) is 20 m. The length of a dead-end corridor should be at most 6.1 m in the absence of sprinklers, as is the case here. Even in the presence of sprinklers, it should not exceed 15.2 m, but the current length exceeds that as well.

c) Existence of a dead-end corridor

d) Sprinkler is absent even though length of a deadend corridor exceeds the safe length.


110

Furnishings and Finishes Analysis: The materials of most furnishings and finishes are combustible, e.g., vinyl wallcovering (30), textile wallcovering (31), wood paneling (34), wood veneers (35), decorative ceiling (41), hardwood flooring (49), draperies (51), vinyl furnishing (57), plastic laminates (60), etc. are used at various places. Despite the significant fire load within the office, the safety measures are minimal, as explained in the fire protection analysis.


111

30 37

60

34

60 48 LUNCH ROOM

49

5’ WIDE CORRIDOR

STAFF AREA

LOUNGE ROOM

48 31 30

48

4’ WIDE CORRIDOR

LADIES TOILET

DIRECTOR’S CABIN

KEY PLAN

37 31

37

34

34

34

48

CONFERENCE ROOM

ENTRANCE DOOR

RECEPTION AND WAITING AREA

DIRECTOR’S CABIN


112

Signage analysis: The signboard shown on the left is the only sign in the entire office. No exit signs or any other directional signs are present in the office, or in the entire building.

a) Exit staicase has an open duct passing through, b) Server room is located in the center and which can be the prime reason for spread of fire/ not adjecent to exterior wall. It also has no smoke across floors when a fire occurs. ventilation.

c) Peon room has a duct passing through, but no ventilation.


113

b.

a.

Despite being a high-rise building, the foyer (Figure a) has no fire-fighting equipment (e.g., sprinklers or fire hoses). Also, no emergency evacuation plan is present in the entire building.

c.

d.

g.

h.

Exit staircase door (Figure c) is itself made of wood. Instead of being fire resistant up to several hours, the door would burn quickly in case of fire, blocking the only egress path to the exterior of the building.

e.

f.

Despite being an 11-storey highrise building with high occupant load, only one exterior exit door is provided (Figure d) for all the occupants to evacuate, which may not be sufficient. High-rise buildings should also have strong ventilation systems to protect against the stack effect of smoke. However, most windows in the building are fixed (Figure f), and the atrium is also closed from above.

Even on the storeys, only a small opening (just the middle of the three windows in Figure g) is provided for ventilation. The foyer (Figure a) has mirror polished Italian marble, but the floors elsewhere, mainly in the corridors and staircases (Figure g), have matt finished vitrified tiles, which partially serve as anti-skid surfaces. While fire extinguishers and fire hoses are given on the floor (Figure g), the detection and alarm systems are very inadequate. Only four heat detectors (and no smoke detectors) are provided on the entire floor (see Figure h), and no heat/smoke detectors are present in the entire office. Only a manual fire alarm is provided near the lift (Figure b). There is no visual alarm, and despite the absence of egress signage, there is no voice communication system to direct the occupants in case of an emergency.


114

CASE STUDY Summary Certain observations can be made based on the checklists that can be positive factors for a space. For example, in the office considered in this case study, there is low occupant load (20), and the occupants have medium-tohigh alertness, mobility, and familiarity with the space. Further, the office is very spacious. These factors suggest that the occupants may be able to evacuate quickly. However, a minimum level of fire protection should be provided in any space. Especially, in this case, the office is part of a building that has very minimal fire protection capabilities. Although fire protection in the building is not directly relevant for this case study, it should be noted that it still affects the safety of the occupants in the office considered here. Hence, inadequate safety measures in the building should be compensated with more-than-adequate measures within the space, which seems to be missing in this case. The case study provides analysis of observations regarding various systems related to building and life safety; these are summarized below. Fire Protection: While fire extinguishing equipment is provided, detection and alarm systems, which are equally important, seem inadequate. Means of Egress: Only one exterior exit door is provided for an 11-storey building. There is insufficient separation between exits and long dead-end corridors, due to which the travel distance from the space exceeds the maximum safe travel distance. Materials and Finishes: Despite the extensive use of combustible materials in the space, no fire/smoke detectors are present. The door of the exit staircase in the building is also made of wood. Building Services: Open ducts passing through exit staircases, and inadequate ventilation in the entire building, and especially in server room, present danger to life safety. Signage: No exit signage is present in the entire building, including the office considered here. Egress signage is extremely important, as its absence may render the other systems useless if the occupants cannot find evacuation paths quickly.


This page is intentionally left blank. Please turn over.


116

Mall: Gulmohar Park, Ahmedabad

Below : Figure 5.5 Shows various observation checklists prepared based on the research presented in this thesis. The checklists continue on later pages, and are accompanied with the corresponding analysis.

Satellite Road, Opp. Satellite Police Station, Satellite, Ahmedabad, Gujarat. Owner : Navratna Organisers and Developers Pvt. Ltd.


117

Closet For Fire Equipment

Sprinkler

Fire extinguishers, hose reel, and standpipe are present, unexpired, visible, and in a closet that is clearly marked.

Audio-Visual Fire Alarm

Audio/visual alarms are present in open areas at appropriate distances where they can properly be seen/ heard by the occupants.

Water Sprinkler System

Sufficient number of sprinklers are present throughout the building, including the basement, at adequate distance.

Voice Air Supply Sprinkler Communication Diffuser System

Smoke Detector

Security Camera

Fire Lift Sign

Manual Fire Alarm Fire Safety PrecautionBoard

Fire Resistance and Building Services Analysis: While passive protection is difficult to observe in a built environment, the active protection system at Gulmohar Park Mall is an excellent example of a well-designed system. Fire detection, alarm, and extinguishing systems are up-to-date, not expired, in well accessible locations, and spread throughout the building. Further, multiple types of equipment are used within each system to increase efficiency. Mechanical ventilation is also present to control fire and smoke. The ceiling-mounted air supply diffusers ensure circulation of fresh air, and exhaust fans provided on the roof remove smoke in case of a fire.

A number of fire protection mechanisms can be observed through this picture. Smoke detectors as well as manual fire alarms are present to detect fire. Sprinklers are present to control/extinguish fire, and air diffusers are present to maintain adequate ventilation, which may help control smoke. In addition to the audio/visual alarm system (from the previous picture), a voice communication system is also present through which occupants may be guided with the egress process, whenever required. Fire lift sign and fire safety precaution signboard are present as additional aid to the occupants.


118

Means of Egress Analysis: Exit accesses, exits, and exit discharges have sufficient width and height. The number of exits and total exit width are in accordance with (in fact, more than what is required by) NBC. Exits are well-separated using the 1/2 diagonal rule, even though sprinklers are present (in which case, they only need to be separated using the 1/3 diagonal rule). However, the travel distance from Point 1 in Figure 5.6 exceeds the maximum safe distance allowed by NBC. The checklist also shows a sample egress sequence from Point 1 in Figure 5.6.


119

4

2 1/3 D

) rox

D

pp ma 7 4 (

D 3 / 1 >

> 1/2

D

1 3

Figure 5.6 TYPICAL PLAN OF THE GULMOHAR PARK MALL

Site Plan

By, Kapadia Associates (2008)

SCALE NTS (The drawing presented here is just for the reference)

 2 Figure 5.6 shows the egress paths from four different pointsAHMEDABAD in the space. There are 6 exits from the space, which are marked in green circles in the figure. The separation between various exits is also shown in the figure. KSHITIJ MALL (GULMOHAR PARK),

The codes require at least two of the exits to be separated by at least one-third of the longest diagonal in the presence of sprinklers (the requirement increases to one-half in their absence). The longest diagonal is shown in the figure as D, which is the distance between Point 1 and Point 4. The exits close to Point 1 and Point 4 are more than 1/2 D distance apart from each other. Hence, 1/2 diagonal rule is followed.


120


Mall Entry Disclaimer

Temporary Fabric Pannels

32

37a

36

47

Fire Exit wall Sign

37a

Return Air Grills

33

Directional Signboard with Exit Sign in Green Colour

33

35

Electrical Illumination of Exit Signboard

48

60

60

121

60

60

35

61

Interior Materials and Finishes Analysis: The figures presented above show the use of various materials from the checklist. Permission could not be obtained for taking photographs of the materials used in some of the locations due to security reasons. However, it is evident that most of the materials used in the furnishings and finishes are noncombustible. While this reduces the level of fire protection required, high level of protection is still provided due to the high occupant load. Signage Analysis: The space contains many display signboards. Egress signage is adequate in number (both in the building and in the basement). Exit signs are green in colour and electrically illuminated at all times. However, NBC requires such signs to display the word â&#x20AC;&#x153;EXITâ&#x20AC;?, which is missing in this case. Further, the exit signs are very small in size, and not clearly visible from far. There are a number of outdoor display signboards (wall mounted and ground mounted), all of which are properly anchored.


122

CASE STUDY Summary In this case study, the ground floor of the Gulmohar Park Mall, Ahmedabad is studied. All the storeys above the ground floor are typical, and similar to the ground floor in layout. Due to the limited scope of the case study, they are omitted. Overall, Gulmohar Park Mall is an excellent example of a space well-designed for occupant safety. All safety-critical systems in the interior of the space are adequately designed. The case study presented above provides many observations to support this, which are summarized below. Occupancy: The space considered is an Assembly occupancy with the occupant load of approximately 800 (only considering the ground floor) in its peak time. Due to the high number of occupants, relatively less space per occupant, and elderly and children being present among the occupants, the egress process would be slower in case of an emergency. To support this, adequate fire-fighting equipment are provided. Fire Protection: Fire detection, alarm, and extinguishing systems may proove to be effective as multiple types of equipment are used in each system. Means of Egress: Six well-separated exits provide sufficient room for the occupants to evacuate. They meet the width and height criteria, but the travel distance slightly exceeds the maximum safe distance suggested by NBC. The evacuation plan was present earlier, but later it was removed due to “security reasons”. While this may cause inconvenience in locating the exits, egress signage is provided to make up for it. Although, the exit signs are small in size and not properly visible from far away. Materials and Finishes: Most of the materials used are noncombustible materials such as stones, metal sheets, vitrified tiles or paint as a finish. Combustible materials are rarely used, e.g., textile wallcoverings are not used and vinyl wallcoverings are hardly used. Building Services: Mechanical ventilation is present in the space with air supply diffusers and return grills spread throughout the space. Additionally, six large exhaust fans are provided on the roof to remove smoke in case of a fire. The system is monitored from the mechanical room. Signage: Exit signs are well placed (close to the exits), green in colour, and electrically illuminated at all times. However, they are small in size (thus not clearly visible from far), and do not contain the word “EXIT”, which is required by NBC. Outdoor display signboards are anchored properly. In general, studying the design of Gulmohar Park Mall illustrates how adequately chosen interior design decisions regarding various systems can jointly ensure the safety of the occupants. Note: Due to security reasons, the author did not have the permission to take photographs of some of the details in the case study or document other details. However, the author has personally verified all the details given.


6

123

Conclusion


124

Thesis Aim and Summary Interior Design, Building Codes, and Life Safety

Importance of Interior Design Concepts for Safety

Building mishaps resulting in loss of property and human lives are very common these days, and yet building codes are not strictly followed in India. The thesis begins with a brief survey of these mishaps highlighting concerns such as the lack of awareness regarding safety in general, and regarding the impact of design decisions on building and life safety, in particular. The situation may be amended by a deeper conceptual understanding of the consequences of design decisions, which may aid an interior designer to evaluate his/her decisions from the safety viewpoint. Such an understanding may also make it easier to follow the codes that are otherwise tedious long lists of factual specifications which simply describe what choices should or should not be made. To that end, this thesis studies the concepts of interior design related to building and life safety, and uses them to illustrate the interdependence of the design decisions. The thesis describes various interior aspects through which a designer may contribute to building and life safety, some of which are summarized below. Take the case of fire hazard, which is one of the greatest hazards possible in a building. • The choices of interior materials, furniture, and finishes determine the amount of combustible material in a space, and how quickly fire or smoke may spread. The interior designer may be able to create certain compartments in the interior of a building to contain the fire locally. Adequate ventilation system may also help keep the smoke to a minimum. • By carefully designing the electrical systems, an interior designer can eliminate a major cause of fire. • The type and locations of sprinklers, fire extinguishers, and other firefighting equipment can prevent loss of many lives by detecting and extinguishing fire in its early stage. • Well-illuminated egress paths, easily accessible door hardware, and adequate egress signage can facilitate quick and safe occupant evacuation. • Case studies presented at the end demonstrate how safety-critical details can be observed in a built environment, and show the relations between design decisions using such observations.

Limitations of the Study

The contribution of this thesis is bound by certain limitations. While safety should be viewed as a joint outcome of all design decisions, the thesis only helps evaluate the “interior design decisions” from the safety viewpoint. Moreover, other criteria such as comfort and aesthetics should also be kept in mind, which are beyond the scope of this thesis. Finally, the thesis only focuses on commercial spaces in India, but this is not very restrictive as the concepts do not change from place to place, even if the specifications do.

Conclusions from The Study

Despite these limitations, some generic conclusions with significant practical importance can immediately be drawn from this study. To begin with, safety in a space is not the sole result of structural or architectural aspects. Careful choices in numerous interior aspects also play a key role in achieving safety. Hence, the design of a space should be an all-inclusive process where safety considerations are elicited from all design professionals before making critical decisions; although, considering all such parameters simultaneously may prove to be exhausting at times.


125 This is where building codes jump in. They aid an interior designer by highlighting the design choices that may endanger safety. In this regard, building codes should not be viewed as barriers that limit the possibilities.

Building Codes as an Aid

However, in India, there may be one difficulty in codes aiding interior designers. As explained in a brief review presented at the beginning of this thesis, NBC India is written from a more architectural viewpoint. Many interior details are either missing or not given due importance. This suggests that building codes in India should be revised, especially to incorporate more interior details.

Codes and the Need for Their Revision

After revising the codes, it is also important to ensure that they are followed rigorously. One possibility is to establish detailed inspection and permit procedures for interior drawings similarly to the existing procedures for architectural drawings. This also requires developing interior drafting standards that specify how interior details should be represented in the drawings.

Codes, Inspection Procedure and Drafting Standards

But building codes themselves are not sufficient.

Relevance of the Study

• There is a need to spread greater awareness regarding the importance of safety measures among the design practitioners as well as the occupants, for which this thesis makes relevant contributions. The thesis directly contributes by serving as a reference to the current practitioners regarding the relevance of interior design concepts to building and life safety. In fact, awareness for building and life safety should be implanted at a very early stage by introducing the required concepts during the academic journey of design students (the future practitioners). The observational methodology of the case study may prove to be helpful for the occupants to understand the safety measures used in their habitat. One should always remember: It takes both hands to clap.

Awareness for Life Safety

• Building codes only help define the perimeter of safe design choices. Future directions may include an investigation of methods and tools that assist in further narrowing down to the optimal choices; one promising avenue in this regard seems to be systems thinking, a framework that aids the thinking process by outlining the trade-off among various design choices.

Future Direction

The implications of this thesis also touch upon the role and significance of an interior designer in a design team. The complex web of dependencies among design decisions makes it substantially harder to apply “patches” or “fixes” at a later stage than to incorporate additional considerations during the design stage. This suggests involving interior designer from the very beginning of the design process in order to ensure safer habitat for the users.

Implication of The Study

A widespread inception of the idea to make joint effort towards safety may result in safe buildings, less mishaps, and a better world! Ensuring safety is a dream, and teamwork can make the dream work.

Role of an Interior Designer


126

Appendix A: History of Building Codes

Copyright © 2012. Wiley. All rights reserved. May not be reproduced in any form without permission from the publisher, except fair uses permitted under U.S. or applicable copyright law.

HISTORY AND PRECEDENTS

A brief codescityleads to the Variouscontemplation civilizations over theabout centuriesregulatory have The various codes us and directly often conflicting developed building codes. The origins of the codesa were over the years one and began thought-provoking question: Why should lawrefined regulate what can or codesdo wewith use today lie in the great fires that The to answer be broughtlies together by regional nongoverncannot one’s own property? in the fact that our acswept American cities regularly in the 1800s. mental organizations to develop so-called model tionsChicago may have adverse effects well-being and vice-versa. developed a building code in on 1875others’ to codes. The first model codes were writtenIndeed, from this placate is thethe reason laws and standards been developed. Nationalvarious Board of Fire Underwriters, the pointhave of view of insurance companies to

“Ifa builder a builder buildforasome house “If build a house for and some and does not one, does one, not construct it properly, and the houseitwhich he built fall construct properly, andin and the kill its owner, then that house which he builder built shall fallbein put to death. and kill its owner, then that builder shall be put to death.

If it kill the son of the owner, the son of that shallson be put death. If itbuilder kill the oftothe owner,

the son of that builder shall

If it kill a slave of the owner, then he be put to death. shall pay slave for slave to the owner of house. If the it kill a slave of the owner,

then he shall pay slave for

Ifslave it ruin goods, he shall make of the to the owner compensation for all that has been house. ruined, and inasmuch as he did not construct thishe house which he If it ruinproperly goods, shall make built and it fell, he shall thehas compensation forre-erect all that house from his own means.

been ruined, and inasmuch as did not properly Ifhe a builder buildconstruct a house for some one, this house which he built and even though he has not yet completed it iffell, hewalls shall re-erect the it; then the seem toppling, the builder make wallsmeans. solid from housemust from histheown his own means.”

If a builder build a house for

some one, even though he Laws 229–233 Hammurabi’s Laws has not Code yet ofcompleted it; (ca. 1780 BC) if then the walls seem top-

pling, the builder must make

From a stone slab discovered in 1901 the walls solid from his own and preserved in the Louvre, Paris.

means.”

Laws 229–233 Hammurabi’s Code of Laws (ca. 1780 BC) From a stone slab discovered in 1901 and preserved in the Louvre, Paris. 2 / BUILDING CODES ILLUSTRATED

who threatened to cut off insurance for busi- reduce fire risks. Model codes are developed nesses after the fire of 1871. It is essential to by private code groups for subsequent adopThe keep earliest reference to regulatory codes dates as far back as the eighthe fire-based origins of the codes in mind tion by local and state government agencies as teenth century BCE tothe the Codebehind of Hammurabi fromregulations. Babylonia Figure legally enforceable The (see first major when trying to understand reasoning many codethis requirements. model-code group was thefor Building and he A). Under code, the builder was held accountable theOfficials houses (BOCA), in 1915 built under the principle of “an eye forCode an Administrators eye”, where thefounded builder would and located in Country Club Hills, Illinois. Next have to sacrifice an arm or even his life ifwas a person lost his arm oroflife respecthe International Conference Building tively. Later evidence from archeological fragments of Greek Roman Officials (ICBO), formed in 1922, and located in Whittier, California.for Thethe first construction edition of their of laws contains codes that have explicit requirements Uniform Building Code was published in 1927. a building in 341 BC by Socrates: “He shall set the joints against each other, The Southern Building Code Congress, foundfitting, and before inserting the dowelsedhe shallandshow the architect all the in 1940 headquartered in Birmingham, Alabama, published thedowel Southernthem Buildingwith stones to be fitting, and shall set them true andfirst sound and Code in 1946. The first BOCA National Building iron dowels, two dowels to each stone…”. Code was published in 1950.

National Building Code of India In India, the ground work for modern building codes was set in 1965, when a panel of experts was appointed by the Planning Commission to study various aspects of construction in depth. The “Report on Economies in Construction Costs” published in 1968 contained various recommendations from the panel. A prominent recommendation made was the requirement of byelaws and departmental handbooks as it was observed that the construction methods of that time were outdated and some of the designs had serious safety concerns. This led to the establishment of the Bureau of Indian Standards (then called the Indian Standards Institution). A committee of 18 experts (architects, planners, material experts, etc.) prepared various parts of the first version of the National Building Code of India published in 1970.[1] This was followed by an extensive effort to implement the code in all concerned fields. Many conferences were held to bring awareness among the practitioners in the construction industry. Building byelaws for local bodies (cities, towns, villages, etc.) were developed to make them consistent with the National Building Code of India. A large number of comments and suggestions were received during the process, which were incorporated in a revised edition published in 1983.[2] Finally, a third (and the latest) revision was published in 2005[3], which primarily incorporated accumulated wisdom on protection against natural calamities such as earthquakes and tsunamis, aspects of green and sustainable development, and detailed fire prevention, life safety, and fire protection guidelines.

Other Codes

EBSCO Publishing : eBook Collection (EBSCOhost) - printed on 3/1/2014 7:37 AM via CARNEGIE MELLON UNIV AN: 463065 ; Ching, Frank, Winkel, Steven R..; Building Codes Illustrated : A Guide to Understanding the 2012 International Building Code PDFAbove Watermark Remover DEMO : Purchase from www.PDFWatermarkRemover.com to remove the : Figure A Account: s8368349

Adapted from Ching, F. D. K., and Winkel, S. R. “Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code” Wiley Publishing, 2012, p.2.

Many organizations and legislative bodies worldwide have generated variwatermark ous codes and adopted them. Perhaps the most prominent of them is the International Building Code (IBC) developed by the International Code Council (ICC) in 2000.[4] This was a grand effort to unify all the existing standards (also known as model codes) in the United States. The IBC has been


127

adopted throughout most of the United States and it is regularly updated every three years, with the latest edition published in 2012.[5] Other major standards include the codes and standards developed by the National Fire Protection Association (NFPA) and accessibility standards enacted originally by the Americans with Disabilities Act of 1990[6] and revised later by the U.S. Department of Justice in 2010.[7] Among the codes and standards developed by the NFPA, NFPA 101[8] — the Life Safety Code — would be especially important in this thesis.

Difference between Codes and Standards Codes and standards are both written by regulatory bodies consisting of panels of experts. However, standards are not binding, whereas codes are adapted by a legislative body, making them part of the legislation and binding to all individuals and agencies within the jurisdiction of the legislative body. Codes are often a subset of standards and represent the minimum set of requirements; the choice of materials and methods of design and construction is often left to the building professionals.

Life Safety and Property Loss The objectives of modern regulatory codes are twofold. The primary objective is clearly to prevent loss of human lives. But there is also another strong objective of preventing property loss in terms of damage or destruction. Many protective systems, for example, fire extinguishing systems serve both purposes: On the one hand, extinguishing fire helps the occupants to evacuate safely, and on the other hand, it also prevents damange to property and building structure. In summary, these requirements exist for the purpose of ensuring safety of the public with regard to structural sufficiency, fire hazards and health aspects of buildings. Bottom line is: The building codes exist, and we are obligated to follow them.

1. The National Building Code of India. Bureau of Indian Standards, 1970. 2. The National Building Code of India. Bureau of Indian Standards, 1983. 3. The National Building Code of India. Bureau of Indian Standards, 2005. 4. The International Building Code. International Code Council, 2000. 5. The International Building Code. International Code Council, 2012. 6. 1990 Ada Standards for Accessible Design. United States Department of Justice, 1990. 7. 2010 Ada Standards for Accessible Design. United States Department of Justice, 2010. 8. NFPA 101: Life Safety Code. National Fire Protection Association, 2012.

Note: The designer is often expected to meet quality levels higher than the minimums set by the codes. This is legally known as the “standard of care”. The standard of care is not an objective measure like the codes, but rather a subjective measure.


128

Appendix B: Units and Abbreviations Length • • • • •

mm = milimetres cm = centimetres m = metres in. = inches ft. = feet

• •

1 inch = 25.4 mm 1 foot = 304.8 mm

Area • • •

sq. m = m2 = square metres sq. in. = square inches sq. ft. = square feet

• •

1 square inch = 645.2 mm 1 square foot = 0.0929 m2

Volume •

1 gallon = 3.785 litres

Weight • •

kg = kilograms lbs = pounds

1 pound = 0.454 kg

Temperature • •

oC = degree Celsius oF = degree Fahrenheit

oC = (oF - 32)/1.8


Appendix C: Available Code Resources Today, various building codes are available that an interior designer in India can refer to; a number of such codes can be found in the notes at the end of various chapters and sections of this thesis. Here, a more detailed list of available code resources is provided. These codes are primarily developed by three organizations.

The Bureau of Indian Standards (BIS) The National Building Code of India (NBC) developed by BIS is the primary reference for interior designers in India. BIS has also developed various Indian Standards listed at the end of different parts of NBC. A complete list of the standards can be found at https://law.resource.org/pub/in/bis/.

The International Code Council (ICC) The International Building Code (IBC) is the most important among all codes produced by ICC. A complete list can be found at http://www2.iccsafe.org/ cs/codes_list.cfm. Some of the codes relevant for this thesis are listed below. • • • • • • •

IBC: International Building Code® IFC: International Fire Code® IPC: International Plumbing Code® IMC: International Mechanical Code® ICC EC: ICC Electrical Code™ - Administrative Provisions IRC: International Residential Code® IEBC: International Existing Building Code®

The National Fire Protection Association (NFPA) Since this thesis focuses on building and life safety, the Life Safety Code (NFPA 101) is the most important for this thesis among all codes developed by NFPA. A complete list of all such codes can be found at http://www.nfpa. org/codes-and-standards/document-information-pages. Some of the codes relevant for this thesis are listed below. • • • • • • • • • • • • •

NFPA 1: Fire Code NFPA 10: Standard for Portable Fire Extinguisher NFPA 13: Standard for the Installation of Sprinkler Systems NFPA 70: National Electrical Code® NFPA 72: National Fire Alarm and Signaling Code NFPA 80: Standard for Fire Doors and Other Opening Protectives NFPA 92: Standard for Smoke Control Systems NFPA 96: Standard for Ventilation Control and Fire Protection of Commercial Cooking Operations NFPA 101: Life Safety Code® NFPA 170: Standard for Fire Safety and Emergency Symbols NFPA 204: Standard for Smoke and Heat Venting NFPA 220: Standard on Types of Building Construction NFPA 5000: Building Construction and Safety Code®

129


130

Appendix D: Observation Checklists Occupancy Checklist (Chapters 1 and 2) Occupancy Risk Factors/Hazards (Chapter 2): 1. Total No. of Occupants (Occupant Load, Section 2.3):

………………....

2. Occupant Density

High

Medium

3. Age-wise Classification of Occupants (%)

Elderly…...... Middle aged…...... Young…...... Children…......

Low

a. Average Alertness of Occupants

High

Medium

Low

b. Average Mobility of Occupants

High

Medium

Low

4. Occupants’ General Familiarity with Space

High

Medium

Low

5. Are hazardous materials stored or used?

Yes / No

Occupancy Considerations: Occupancies (Section 2.1):

Single

Multiple

In case of multiple occupancies, they are:

Separated

Non-separated

Occupancy Types

Occupancy 1 Occupancy 2 Occupancy 3 Incidental Use* Accessory Use*

Occupant Load

Fixed Seating?

* See Section 2.2.1 for definitions.

Building Construction Considerations (Chapter 1): Construction Types (Section 1.1):

.................................... (If known)

Required Area Per Occupant (Occupant Factor, From Table 2.3 of the thesis): ………………………… Required Minimum Total Area (Occupant Factor * Total Occupant Load) : Given Area:

.................................... m2

Building Height:

.................................... m

………………………… m2

Number of Storeys ............

Remarks: ................................................................................................................................................................................ ……………………………………………………………………………………………………………………………………………………………………………………………

Mechanical Checklist (Section 3.5) Note: This checklist refers only to the mechanical system within the interiors of the space considered. Most details are usually concealed in a built environment (e.g., elements inside plenum), and thus the corresponding observations are omitted.

Is mechanical ventilation present? Yes / No Type of Air Supply System: ........VAV

......CAV

......All Water System

......Air and Water system

Location of Mechanical Room (if present): ………………………………………………………………. Ceiling Height: .................................. Type of Air Circulation:

......Other

Size: …………………………………..

Minimum Clearance (in case of uneven/tapered ceiling) …………………………….. ........Duct

........Plenum

Type and Locations of Exhaust System (If commercial kitchen, Type I or Type II hood): .................................. Type and Locations of Supply Diffusers (Ceiling / Wall / Floor): ………………………………………………………………… Type and Locations of Return Grills (Ceiling / Wall / Floor):

.…………………………………………………………………

Remarks: …………………………………………………………………………………………………………………………………………………………………………..

Electrical Checklist (Section 3.4) Note: Most details of electrical systems such as cabling, conduits etc. are usually concealed in a built environment. Hence, this checklist is omitted.

Fire Resistance Checklist (Sections 3.1.3 and 3.1.4) Passive Protection (Section 3.1.3)

Smoke Barriers and

Through-Penetration


131 Means of Egress Checklist (Section 3.2) Type of Space (describe here and tick one of the choices below): Building ……… Floor ……… Space with multiple rooms ……… Single Room ……… Other ……… Exit Access Requirements (Section 3.2.2): 1. Components:

......Doors ......Stairs ...... Ramps ......Corridors ......Aisles ......Intervening Rooms

2. Width:

Required.............................. m Given.............................. m

3. Height:

Required.............................. m Given.............................. m

(Take the minimum height and width across the common path of travel, see Section 3.2.3.2)

Exit Requirements (Section 3.2.3): 1. Are exits part of the interior? 2.

Required Number of Exits: (Section 3.2.3.1)

3. Given Number of Exits: 4.

Exit Breakdown:

......1

......2

......3

......≥ 4

......1

......2

......3

...... ≥ 4

……. Exterior Exit Doors ……. Horizontal Exits ……. Others (explain)

(Section 3.2.3.4) 5.

Yes / No

Total Exit Width (Section 3.2.3.3) a. Is Occupant Load through the exit known? Yes / No b. Occupants per Unit Width (Table 3.2.3.3 of the thesis):

If yes: ……………………………………. ………………………………………………….

c. Required Total Exit Width (Occupant Load / Value in 5b) : ……………………… m d. Given Total Exit Width: ……………………… m 6.

Exit Separation Followed (Section 3.2.3.2) (Check one and show in plan)

Mechanical Checklist a. ½ Diagonal Rule (Section 3.5)

b. ⅓ Diagonal (If so, system are sprinklers present? / No) Note: This checklist refers onlyRule to the mechanical within the interiors Yes of the space considered. Most details are usually concealed in a built environment (e.g., elements inside plenum), and thus the corresponding observations are omitted.

c. Other (explain) .................................... Is mechanical ventilation present? Yes / No 7. Travel Distance (Section 3.2.3.2) (check and indicate length those that apply and indicate lengths where required) Type of Air Supply System: ........VAV ......CAV ......All Water System ......Air and Water system ......Other a. Maximum travel distance allowed (Table 3.2.3.2 of the thesis): …………………….. m Location of Mechanical Room (if present): ………………………………………………………………. Size: ………………………………….. b. Maximum travel distance in the space: …………………….. m

Ceiling Height: .................................. Minimum Clearance (in case of uneven/tapered ceiling) …………………………….. c. __Common Path of Travel Distance: ………………………. m Type of Air Circulation: ........Duct ........Plenum d. __Dead-End Corridor Length: ……………………… m TypeDischarge and Locations of Exhaust(Section System3.2.4): (If commercial kitchen, Type I or Type II hood): .................................. Exit Requirements Type1.and Locations of Supply Diffusers (Ceiling / Wall / Floor): ………………………………………………………………… Type: ......Main Lobby ......Foyer ......Vestibules ......Discharge Corridors ......Exit Courts Type and Locations of Return Grills (Ceiling / Wall / Floor): Egress Sequence:

.…………………………………………………………………

Remarks: ………………………………………………………………………………………………………………………………………………………………………….. …………………………………..  …………………………………..  …………………………………..  ………………………………….. 

Electrical Checklist (Section 3.4)

…………………………………..  …………………………………..  …………………………………..  ………………………………….. Note: Most details of electrical systems such as cabling, conduits etc. are usually concealed in a built environment. Hence, this

Remarks: checklist is ............................................................................................................................................................................. omitted.

Fire Resistance Checklist (Sections 3.1.3 and 3.1.4) Passive Protection (Section 3.1.3) Fire Barriers and Partitions

1. 2. 3. 4. 5.

Fire Walls Fire Areas Occupancy Separations Incidental Use Rooms Means of Egress Component 6. Floor/Ceiling Assembly

Smoke Barriers and Partitions

7. Smoke Compartments 8. Vestibules

Opening Protectives

9. Rated Door Assembly a. Fire Doors b. Smoke Doors 10. Fire Window Assembly 11. Rated Glazing and Frame

NOTE: Remember that fire and smoke barriers need to be considered both vertically and horizontally.

Active Protection (Section 3.1.4) Detection Systems Alarm Systems 16. Smoke Detectors 19. Visual/Audible Alarms 17. Heat Detectors 20. Audible only

Extinguishing Systems 25. Fire Extinguishers 26. Standpipes

Through-Penetration Protectives

12. Firestops 13. Fireblocks 14. Draftstops 15. Damper Systems a. Fire Dampers b. Smoke Dampers


132

5. Means of Egress Component 6. Floor/Ceiling Assembly

11. Rated Glazing and Frame

a. Fire Dampers b. Smoke Dampers

NOTE: Remember that fire and smoke barriers need to be considered both vertically and horizontally.

Active Protection (Section 3.1.4) Detection Systems Alarm Systems 16. Smoke Detectors 19. Visual/Audible Alarms 17. Heat Detectors 20. Audible only 18. Manual Fire Alarms 21. Visual only 22. Voice Communication 23. Accessible Warning 24. Emergency Alarms

Extinguishing Systems 25. Fire Extinguishers 26. Standpipes 27. Fire Hoses 28. Sprinkler Systems 29. Alternate Systems

Furnishings and Finishes Checklist (Chapter 4) Wall Finishes

Furnishings and Finishes Ceiling Finishes Floor Coverings / Finishes

30. Vinyl Wallcovering

38. Ceiling Tile

31. Textile Wallcovering

39. Textile Ceiling

32. Stone

Window Treatments

Furnishings/Furn iture

44. Carpet

51. Draperies

56. Fabric

(Broadloom)

52. Liners

57. Vinyl/Leather

Finish

45. Carpet Tile

53. Blinds

58. Seating

33. Light-Transmitting Plastics

40. Plastic Light

46. Rugs

54. Wood

59. Mattresses

34. Wood Paneling

Diffusing Panels

47. Doormat

Shutters

60. Plastic

35. Wood Veneers

41. Decorative Ceiling

48. Resilient Flooring

55. Other

Laminates/

36. Glass

42. Decorative

49. Hardwood

Veneers

Molding/Trim

Flooring

61. Other

43. Other

50. Other

37. Other

a. Paint

a. Paint

Remarks: ………………………………………………………………………………………………………………………………………………………………………

Signage Checklist (Sections 3.2.5 and 4.2) Egress Signage (Section 3.2.5.1): Are ‘Exit’ signs present? Yes / No Exists (Yes/ No)

Type of Sign

No.

If yes, then:

Location

Remarks

Ceiling Mounted Exit Sign Ground Mounted Exit Sign Exit Sign with Directional Arrows  On Staircases 1. On latch side? Yes / No 2. Distance from door: Dimensions:

Ground Mounted Near Exit Doors Floor Numbers (Staircase Landings) Other Signs (explain): ........................................................................................ Are exit signs green in colour? Yes / No

If no, what colour is used? ....................................

Is electrical illumination used? Yes / No

If no, what type of illumination is used? ……………………………………………..

Are exit signs lit all the time?

Yes / No

If no, provide details: …………………………………………………………………………..

Is exit marking present?

Yes / No

If yes, provide details: .............................................................................

Is emergency lighting present? Yes / No (Section 3.2.5.2)

If yes, provide locations: ………………………………………………………………………

Outdoor Display Signboards (Section 4.2)

Type of Sign: Placement: Material: Illumination: Remarks:


Bibliography

133

Works Cited CODES & Books 1. The National Building Code of India. Bureau of Indian Standards, 2005. 2. The International Building Code. International Code Council, 2012. 3. The International Plumbing Code. International Code Council, 2012. 4. The International Mechanical Code. International Code Council, 2012. 5. 2010 Ada Standards for Accessible Design. United States Department of Justice, 2010. 6. NFPA 70: National Electrical Code. National Fire Protection Association, 2012. 7. NFPA 101: Life Safety Code. National Fire Protection Association, 2012. 8. NFPA 110: Standard For Emergency and Standby Power Systems. National Fire Protection Association, 2013. 9. NFPA 111: Standard on Stored Electrical Energy Emergency and Standby Power Systems. National Fire Protection Association. 2013. 10. NFPA 5000: Building Construction and Safety Code. National Fire Protection Association, 2012. 11. Harmon, S. K., and Kennon, K. E. The Codes Guidebook for Interiors. John Wiley & Sons, 2011. 12. Ching, F. D. K., and Winkel, S. R. Building Codes Illustrated: A Guide to Understanding the 2012 International Building Code. Wiley Publishing, 2012. 13. L. Godsey, Interior Design: Materials and Specifications, Fairchild Books, 2008. 14. Barnett, C., Sfintesco, D., Scawthorn, C., and Zicherman, J.B. Fire safety in tall buildings. Council on Tall Buildings and Urban Habitat. Committee 8A. McGraw-Hill, 1992. 15. Xing, Rihan. Commercial Space. H.K. Rihan International Culture Spread, Hong Kong, 2009. 16. Walsh, Vincent. Supreme Court on Children. Human Rights Law Network, New Delhi, 2011.

Articles 17. Nair, R. R. Fire and Explosion Hazards. Industrial Safety Review, January 2013. 18. Nair, R. R. Electrical Hazards. Industrial Safety Review, October 2012. 19. Nair, R. R. Equipment for Fire Protection. Industrial Safety Review, November 2013. 20. Eureka Forbes. Now, prevent fire before it spreads! Industrial Safety Review, December 2012.

Web Links 21. Cook, L., Yan, H., and Udas, S. Decorator responsible for building collapse, killing 61. CNN. 30 September 2013. Accessed 1 April 2014. <http://edition.cnn.com/2013/09/29/world/asia/ mumbai-building-collapse/>. 22. Rajagopal, Shyama. Blowing out chance of fire hazards. The Hindu. 30 April 2011. Accessed 1 April 2014. <http://www.hindu.com/pp/2011/04/23/stories/2011042353880400.htm>.


134 23. Horror hospital: Fire dept asked AMRI to clear basement in July. Firstpost. 9 Dec 2011. Accessed 1 April 2014. <http://www.firstpost.com/india/40-patients-trapped-in-fire-at-private-hospital-in-kolkata-151524.html>. 24. Jeweller held for Borivli building crash. Times of India. 24 July 2007. Accessed 1 April 2014. <http://timesofindia.indiatimes.com/city/mumbai/Jeweller-held-for-Borivli-building-crash/articleshow/2228648. cms>. 25. VS: All Gas. Ahmedabad Mirror. 12 April 2010. Accessed 1 April 2014. <http://www.ahmedabadmirror. com/printarticle.aspx?contentid=20100412201004120318147846976eaf8>. 26. Overloading may have caused short-circuit. The Times of India. 24 May 2012. Accessed 1 April 2014. <http://timesofindia.indiatimes.com/city/vadodara/Overloading-may-have-caused-short-circuit/articleshow/13457101.cms>. 27. Safety short-circuited. The Times of India, 11 December 2011. Accessed 1 April 2014. <http://timesofindia.indiatimes.com/city/ahmedabad/Safety-short-circuited/articleshow/11066137.cms> 28. 2013 Thane building collapse. Wikipedia. Accessed 1 April 2014. <http://en.wikipedia.org/ wiki/2013_Thane_building_collapse> 29. Stack effect. Wikipedia. Accessed 1 April 2014. <http://en.wikipedia.org/wiki/Stack_effect>.

References Books 1. Binggeli, C., Greichen, P., and McGowan, M. Interior Graphic Standards. Hoboken: John Wiley & Sons, 2011. 2. Binggeli, C. Building Systems for Interior Designers. New York: J. Wiley & Sons, 2003. 3. Hurt, S. L. Codes, Regulations, and Standards in Interior Design. Upper Saddle River, NJ: Prentice Hall, 2012. 4. Ballast, D. K. Interior Design Reference Manual. Professional Publications, 2007. 5. Marks, K. A. Building Codes for Beginners: A Guide for Interior Designers. Washington, D.C: American Society of Interior Designers, 2005. 6. Piotrowski, C. M., and Rogers, E. A. Designing Commercial Interiors. Hoboken, N.J: Wiley, 2007. 7. McGowan, M. Specifying Interiors: A Guide to Construction and FF & E for Residential and Commercial Interiors Projects. Hoboken, N.J: Wiley, 2006. 8. Kilmer, W. O., and Kilmer, R. Construction Drawings and Details for Interiors: Basic Skills. New York: J. Wiley, 2003. 9. Godsey, L. Interior Design: Materials and Specifications. New York: Fairchild Books, 2008.

Articles 10. Avikal Somvanshi. Unsteady buildings. Down to Earth. 6 August 2013. Accessed 1 April 2014. <http:// www.downtoearth.org.in/content/unsteady-buildings> 11. India Risk Survey 2013. Pinkerton, and Federation of Indian Chambers of Commerce and Industry (FICCI). 2013. <www.ficci.com/Sedocument/20228/India-Risk-Survey-2013.pdf>


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Web Links 12. Harmeet Shah Singh. Death toll in India blaze goes up to 91. CNN. 11 December 2011. Accessed 1 April 2014. <http://edition.cnn.com/2011/12/11/world/asia/india-fire/> 13. Kolkata: 89 killed in AMRI hospital fire. NDTV. 10 December 2011. Accessed 1 April 2014. <http://www. ndtv.com/article/india/kolkata-89-killed-in-amri-hospital-fire-six-board-members-arrested-156619> 14. Search continues for dozens trapped in deadly India building collapse. Al Jazeera. 4 January 2014. Accessed 1 April 2014. <http://america.aljazeera.com/articles/2014/1/4/dozens-still-trappedindeadlyindiabuildingcollapse.html> 15. AMRI fire after â&#x20AC;&#x2DC;short circuitâ&#x20AC;&#x2122;. The Times of India. 15 December 2008. Accessed 1 April 2014. <http:// timesofindia.indiatimes.com/city/kolkata-/AMRI-fire-after-short-circuit-/articleshow/3837773.cms> 16. Up to 70 people trapped after Mumbai building collapse. The Journal. 27 September 2013. Accessed 1 April 2014. <http://www.thejournal.ie/mumbai-building-1102678-Sep2013/> 17. Hyatt Regency walkway collapse. Wikipedia. Accessed 1 April 2014. <http://en.wikipedia.org/wiki/ Hyatt_Regency_walkway_collapse> 18. List of Building Types - Commercial Buildings. Wikipedia. Accessed 1 April 2014. <http://en.wikipedia. org/wiki/List_of_building_types#Commercial_buildings> 19. Commercial property. Commercial_property>

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A

Glossary

Accessory occupancy: An occupancy that is ancillary to the main occupancy of the building or portion thereof. Aforementioned, aforesaid: Denoting a thing or person previously mentioned. Aid: To help or support (someone or something) in the achievement of something. Alcove: A recess in the wall of a room. Alleviate: Make (suffering, deficiency, or a problem) less severe. Amid: Surrounded by, in the middle of. Ancillary: Providing necessary support to the primary activities or operation of an organization, system, etc. Asphyxiation: Suffocation, the condition of being deprived of oxygen. Atrium: An open-roofed entrance hall or central court. Automatic sprinkler system: A system of water pipes fitted with sprinkler heads at suitable intervals and heights and designed to actuate automatically, control and extinguish a fire by the discharge of water.

B Bitumen: A black viscous mixture of hydrocarbons obtained naturally or as a residue from petroleum distillation, used for road surfacing and roofing. Blind: A screen for a window, especially one on a roller or made of slats. Buoyancy: The ability or tendency of something to float in water or other fluid. Burgeoning: Rapid growth.

C Canopy: An ornamental cloth covering hung or held up over something, especially a throne or bed. Carriageway: Each side in a road with a dividing strip between traffic in opposite directions.

Casing: The frame round a door or window. Conduit: A tube or trough for protecting electric wiring. Consolidate: Combine (a number of things) into a single more effective or coherent whole. Construction type: A classification of buildings according to the hazards presented by its structural elements. Contaminate: Make (something) impure by exposure to or addition of a poisonous or polluting substance. Contemplation: The action of looking thoughtfully at something for a long time. Convector: A heating appliance that circulates warm air by convection. Coved: Provided (a room, ceiling, etc.) with a concave arch or arched moulding, especially one formed at the junction of a wall with a ceiling.

D Deluge: A severe flood. Demising wall: The partition wall that separates one tenant’s space from another or from the building’s common area such as a public corridor. Discharge: Allow (a liquid, gas, or other substance) to flow out. Down-comer: A pipe for downward transport of water or gas from the top of a furnace or boiler. Draftstop: A material, device or construction installed to restrict the movement of air or smoke within open spaces of concealed areas. Drapery: Cloth, curtains, or clothing hanging in loose folds.

E Egress: The action of going out of or leaving a place. Egress court: A court or yard providing access to a public way for one or more exits of a building. Encase: Enclose or cover in a case or close-fitting surround.


137

H Endothermic: Accompanied by or requiring the absorption of heat. Endurance: The ability to endure an unpleasant or difficult process / situation without giving way. Enlarge: Make or become larger. Exposition: A comprehensive description and explanation of an idea or theory.

F Fire resistance: The number of hours an element of building construction can resist collapse, resist penetration of flame and hot gases, and resist temperature rise on the unexposed face up to a maximum of 180 °C and/or average temperature of 150 °C. Fire zone: Demarcation of a city or area based on the fire hazard inherent to the buildings in the area. Fireblock: Building materials installed to resist the free passage of flame and gasses to other areas of the building through small concealed spaces. Firestop: A fire protection system made of various components used to seal openings and joints in fire-resistance rated wall and/or floor assemblies. Firewall: A fire-resistance-rated wall having protected openings, which restricts the spread of fire and extends continuously from the foundation to or through the roof, with sufficient structural stability under fire conditions to allow collapse of construction on either side without collapse of the wall.

Habitable room: A room occupied or designed for occupancy by one or more persons for study, living, sleeping, eating, kitchen if it is used as a living room, but not including bathrooms, water-closet, compartments, laundries, serving and store pantries, corridors, cellars, attics, and spaces that are not used frequently or during extended periods. Headroom: The space above a person’s head in a room or staircase. Hoistway: A shaftway for the travel of one or more elevators. Hose reel: A cylindrical spindle used for storing a hose.

I Impairment: The state or fact of being impaired, especially in a specified faculty. Inception: The establishment or starting point of an institution or activity. Incidental use: A certain use within an occupancy type that is usually hazardous. Infancy: An early stage of existence. Inferno: A large, dangerously out of control fire. Intermittent: Occurring at irregular intervals; not continuous or steady. Intumescent: (Of a coating or sealant) swelling up when heated, thus protecting the material underneath or sealing a gap in the event of a fire.

L

Fixture: A piece of equipment or furniture which is fixed in position in a building.

Linoleum: A material consisting of a canvas backing thickly coated with a preparation of linseed oil and powdered cork, used as a floor covering.

Flux: The action or process of flowing out.

Luminaire: A complete electric light unit.

Foyer: An entrance hall or other open area in a building used by the public, especially in a hotel or theatre.

M

Fuel load: The amount of flammable material that surrounds a fire. Furring strip: A strip of tapering wood, used in roofing and other construction work.

Marquee: A rooflike structure, often bearing a signboard, projecting over an entrance. Mezzanine: An intermediate floor level between the floor and the ceiling of a room. Mishap: An unlucky accident.


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N Napped: (Of a textile) having the fabric hair raised in a specific direction, in a specific way. Nosing: The rounded edge of a step.

O Occupant factor: The space required for each individual occupant to safely occupy a space. Occupant load: The number of people that can safely use a space. Onus: Oneâ&#x20AC;&#x2122;s duty or responsibility.

P Parapet: A low protective wall along the edge of a roof, bridge, or balcony. Patio: Paved outdoor area adjoining a house.

Separated occupancies: Occupancies that have a fire-rated partition (e.g., walls, floor, and/or ceiling) between them. Smoldering: Slowly burning with no flame. Soffit: The underside of an architectural structure such as an arch, a balcony, or overhanging eaves. Stack effect: Upward movement of smoke due to buoyancy created by the difference of air pressure between the inside and the outside of a building, chimney, flue gas stack, or other container. Standpipe: A vertical pipe extending from a water supply, especially one connecting a temporary tap to the mains. Stringent: (Of regulations, requirements, or conditions) strict, precise, and exacting.

Plenum: An enclosed portion of the building structure, other than an occupiable space being conditioned, that is designed to allow air movement, and thereby serves as part of an air distribution system.

Stud: A large-headed decorative piece of metal that pierces and projects from a surface.

Plethora: A large or excessive amount.

T

Pneumatic: Containing or operated by air or gas under pressure.

Tack: A small, sharp broad-headed nail.

Projecting: Protruding, extending outwards beyond something else. Protected building: A building whose building elements have been treated to increase their fire resistance beyond the natural characteristics of the materials. Pulsing: Turning on and off rhythmically.

R Receptacle: An electrical socket. Refuge area: A space where people unable to use stairways can safely wait for assistance in case of an emergency. Return grill: The space where air returns to be filtered, heated, cooled, or re-circulated.

Supply diffuser: An air distribution outlet. Switchback: A 180° bend in a path.

Temper: The degree of hardness and elasticity in steel or other metal. Transom: A transverse horizontal structural beam or bar, or a crosspiece separating a door from a window above it. Trim: Additional decoration, typically along the edges of something and in contrasting colour or material. Tufted: (Of a bunch of threads, grass, hair, etc.) held or growing together at the base.

V Vestibule: An antechamber, hall, or lobby next to the outer door of a building.

W

S

Wainscoting: Wooden panelling that lines the lower part of the walls of a room.

Sash: A frame in which the panes of a window or door are set.

Winder: A step that narrows toward one end, typically used in a spiral staircase.



Undergraduate Thesis