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Table of Contents
Introduction
5
Results
7
Analysis and Solutions
15
Acknowledgments
19
References
21
Appendix A
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Introduction Just as in any business, machinery needs to be kept up to date, running smoothly, and not overworked or overstressed. Such is the same with human machinery - the employees. In call centers, people are the machinery that keep the systems operating, receive calls, dispatch officers, and keep track of everything. It is as important to maintain the integrity of the machinery as it is to maintain the health, well-being, and safety of the employees. If this is not done correctly, it can mean a severe financial loss to the company as it is responsible for covering the expenses of employees who suffer from strain injuries, stress injuries, and musculoskeletal injuries stemming from job-related problems. The American Academy of Orthopedic Surgeons estimates that jobrelated repetitive strain injuries cost $27 billion a year in medical treatment and the Occupational Safety and Health Administration (OSHA) estimates close to 50 cents out of every dollar spent in medical costs goes to treating repetitive strain injuries (Allie). With 60% of call center costs going toward labor, ergonomically correct working conditions are everybody’s bottom line (Read 2005). Common ailments stemming from poor work environments include eyestrain, back pain, neck pain, carpal tunnel syndrome, and other serious injuries that could be prevented with the implication of ergonomic principles into the office (Allie). It’s proven; for example Verizon Wireless witnessed a 38% drop in carpal tunnel disorders from 2000 to 2001 after the company began a program designed by the ergonomics consulting firm, HumanTech. The benefits of this program far outweigh the costs, as it cut compensation claims by $183,000 (Hersch). The easiest way for an employee to reduce injury and stress is to be alert to their body position and maintain
neutral posture. Neutral posture is preferred by ergonomists because the joints of the body are aligned naturally, reducing strain on the muscles, joints, and tendons. This posture can be maintained while sitting straight up, standing, sitting declined, or sitting reclined. In the upper body the hands, arms, and wrists should be in a straight line and parallel to the floor. Elbows should be at 90 or 120 degree angles to the upper arms, hanging straight down beside the body. Shoulders should be relaxed and the head should be level or bent slightly forward and facing forward, not twisting. Lower down the body, the back should be properly supported with lumbar support whether sitting vertically or reclining. The entire back should be supported, which means the back of the chair should have the capacity to move forward and backward and the body changes position. At the bottom feet should be supported either flat on the floor or with a footrest (OSHA 2003). The goal of this neutral posture forms the basis and standard for which the Rapid Upper Limb Assessment method measures for. This analysis is available in the Results section.
Neutral posture is the key to reducing injury in the workplace.
As agents are working for many hours at a time in the same position it is important to train them in how to perform their tasks without placing uneccessary stress on their bodies and how to use ergonomic equipment properly, and also ensure that the equipment they are using helps minimize the strain placed on them (Dawson 2001, Call Center Magazine 2006). While standard, uniform furniture may fit the budget, it may not fit all people and can be a risk for injury or strain. For example, electronic adjustable-height workstations (EHAWs) are featured in the current call center layout, but are not utilized to their full potential, as noted Cornell Police Communications Center: Ergonomic Analysis and Evaluation
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Introduction
Adjustability of equipment and workplace furniture is essential as well.
in the formal observations method. On one level, EHAWs make it possible for users of different proportions to adjust their workstation to a comfortable height for them - keeping their body in a neutral position and thereby lessening stress on the body. In a study run by Dr. Alan Hedge of Cornell University where participants were given EHAWs the results found that there were significant decreases in the severity of musculoskeletal disorder symptoms for most areas of the upper body. Not only this but discomfort ratings were lower at the end of the day after participants switched to EHAWs and self rated productivity was higher. Desks aren’t the only pieces of equipment that need to be taken into account (Hedge 2004). Poorly designed chairs are another common source of musculoskeletal strain and injury, especially in jobs where employees are seated for many hours at a time, as they are in the call center. Telephones, keyboards, mice, monitors, and headsets are pieces of equipment that pose threats, and ambient conditions such as lighting, glare, and noise all play a part in body stress leading to strain and injury. This seems like a very bleak look at the situation, but making an office ergonomically correct is far easier than it seems. Through a combination of formal observations, analysis, and interviews we have identified threats to physical and environmental comfort and provided ergonomic solutions, both short term and long term, that will help remedy these. As human capital is the biggest expense in call centers we made sure to use employee input in our analysis. Our solutions include theoretical and applied solutions concerning both equipment and education, and we have separated our results and recommendations into three sections: equipment, communications, and ambient
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conditions.
Results Equipment
the machine is dated.
Interviews
Adjustable desks are used at both main stations and everyone finds them easy to adjust, in theory. In reality the issue that came up was a case in which employees want to do their work standing up for short periods of time to alleviate back pain. In these situations, the computer monitors did not have long enough cables to reach a comfortable standing level. Some people adjust their chairs but there is no consistency as some chairs are not adjustable. Employees also said that each person usually preferred a particular chair, and depending on which shift began the earliest other employees were left with a small selection. The chairs are all different brands and models, some were designed for call center use while others were designed for light office use. Employees also reported that there was a discrepancy in what equipment was available at each station, as one station has the Police Records monitor and the other has the fire panel monitor. If one employee needs to see a piece of equipment that is not at their station they have to either get up and record what they need or ask their co-worker to do it.
Through interviews with all of the employees, it was determined there were several common concerns shared among the employees about the current equipment. Out of the equipment, it was determined that the phone, the radio dispatch system and the computer were most necessary to the job. Accessories and interface devices for these systems see constant use throughout every shift. Each station had a minimum of four sets of keyboards and 3 mice in order to interface with multiple systems. Phones were one piece of equipment that required constant user interaction and received poor reviews. Phone calls can be under a minute but can range up to an hour in some extreme cases, and no matter the length of calls the feelings about the phone system were consistent across almost all employees. The only headsets available for use were wired headsets which were unpopular with most of the employees. Most of the respondents said they did not like the headsets because they were not wireless and the employees felt limited in their range of motion, attached to their work station, uncomfortable, and tangled in the wires. Only one employee reported using the headset because it connects to both the phone and the radio and it was more convenient for him and leaves his hands free. Most reported the equipment became fairly easy to use once trained. One shorter employee said it was difficult to reach and use the equipment as it was too spread apart, and to use it they had to get up. One employee responded they would like the computers to do more and monitor the burglar alarm, fire alarm, cameras, floor plans and maps, using more up-to-date technology. One said accessing the state records is hard and
Methods: - Formal observation - Interviews - RULA analysis
Formal Observations
We decided to make observations to gain a better understanding of how employees interacted with their environment. Attention was paid to observing what types of activities the control center personnel were engaged in, with whom they were communicating, what equipment was being used and how it was used. Physical traces were also noted because by observing physical traces, we could systematically look at physical surroundings to find reflections of previous activity that was not produced in order to be measured by Cornell Police Communications Center: Ergonomic Analysis and Evaluation
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Results researchers (Zeisel, 2006). In an effort to obtain unbiased data, eight students visited the control center on different days and at different times. Two observations were made during the morning shift; four during the afternoon; three during the night. Each observation lasted about 30-60 minutes.
Desks and Chairs: While observing movement within the control room, we noticed that the personnel usually rolled their chairs across the floor to move from one area to another while still sitting in the chair as opposed to walking. General trends of movement are marked in Figure 1. People rolled
D
C
Movement (walk) A
B
Movement (chair slide) Circle of major activity Face direction
Figure 1 | Behavioral Map 8
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Results in chairs to move around between the desks A and B. They made minor movements within the areas immediate to their desks because the various pieces of equipment were spread out. We also found that in many instances the employees’ bodies and heads were facing different objects. For instance, one observer noted that a person’s body was turned to the leftmost computer at Desk B while his head was facing the center monitor. This can be problematic because when the head and the body are not aligned, neutral position cannot be maintained. As a result of this, neck muscles are loaded unevenly and pain and fatigue are increased (OSHA Computer Workstations). We also observed that one person adjusted desk height when she was getting ready to eat. A different employee during a different shift adjusted the height by eyeballing whereas another employee had pre-programmed a preferred height and changed the height by pressing on a button. This suggests that employees have different preferences for desk height and that not all of them utilize the preset height adjustment feature. In addition, the observation also communicated that the desks are used for various activities including office work, eating and reading. Because the employee had her keyboards a bit to the side when eating, we determined that the current desk surface was not large enough to accommodate different activities simultaneously. Phone use: We observed that when people used the telephone (hardware), they sometimes held the receiver between their neck and shoulder. Even though most of the calls observed were brief (under 1 minute), this posture, if maintained for a longer period repeatedly, can put a strain in
the neck-shoulder area. Keeping the phone pinched between the shoulder and the head is a potential hazard according to OSHA (OSHA e-tools, Computer Workstations). The telephones are currently located at the periphery of the desk surfaces while the keyboards are in the middle. As a result, employees who are adjacent to the keyboards have to reach for the phone when they make or answer calls. OSHA also indicates that repeatedly reaching for the telephone can cause strain injuries in the shoulder, arm and neck (OSHA e-tools, Computer Workstations). Use of headsets should be able to mitigate the frequency of reaching. Headset manufacturer Plantronics cites a Santa Clara Valley Medical Center study that shows that headsets reduce neck, upper back, and shoulder tension by as much as 41% (Read 2005). Multiple input devices: Complaints about there being too many mice and keyboards were reported. The observation data testifies to the complaints: during an observation period, one employee was making sticky labels and attaching them on the mice so that employees would be able to tell which one is connected to which desktop. This suggests a strong need for organizing the input devices so that errors can be minimized. Space for messages and personal belongings: There were plastic folder compartments hung up on the wall to the left of the entrance most of which were filled up and did not seem large enough to store items exceeding 8.5x11”. The employees’ personal belongings such as bags and coats were found on the floor or on empty chairs. It was also observed that small scraps of paper were taped onto various pieces of equipment including the monitor. Tacks and magnets were also used to hang notes in various places. The notes usually Cornell Police Communications Center: Ergonomic Analysis and Evaluation
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Results contained reminders or lists of phone numbers. This reflects a need for a place for posting notes that can be accessed easily from where the person is sitting.
RULA Method
We decided to employ the Rapid Upper Limb Assessment (RULA) method as a tool to assess the risk of injury associated with the seated postures of the center’s employees. While the RULA process is quick, it is an excellent tool, providing hard evidence to supplement the findings obtained through other observation instruments. The evaluation focuses primarily on the positioning of the neck, trunk, and upper limbs, thus making RULA an appropriate tool for evaluating seated tasks such as the use of a computer. The assessment also considers the positioning of the legs relative to the chair, and the seated posture of the employee. In observing the call center, the RULA method served as a “snapshot” evaluation, where postures were recorded on digital media and then assessed according to the instrument. RULA operates by assessing the parts of the body incrementally one at a time, assigning a score to each of those areas and essentially adding them together to obtain the final posture score (Appendix A). The final score of a posture can range between one and seven, one being “acceptable” and seven being “investigate and change immediately.” While there are only eight employees at the emergency call center, we felt that ten of the recorded postures required this more detailed assessment. We found that the final RULA scores fell equally into 10
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Figure 2 | Frequency of Final RULA Scores
two intervals: half of the recorded postures were found to be at a mid-range risk factor of three or four, and half were found to be at a high risk factor of six or seven (figure 2). In examining the incremental scores corresponding to individual parts of the body, we determined the areas that most frequently contributed to higher overall scores. Incremental scores were considered high if they ranked above the midpoint of possible points alloted for that particular body feature. Using this system, it was determined that overall the most frequent at-risk features of the body were the forearm position and the degree of support and balance of the legs. Figure 3 illustrates the frequency of these high-ranking features; features not included on this graph were consistently found to be at non-elevated levels (figure 3). Arms: The lower arms were often observed working
Results
Figure 3 | Frequency of RULA High Scores per Body Feature
across the midline of the body, and out to the side of the body (figure 4). This is largely due to the fact that there are multiple monitors and multiple corresponding keyboard and mouse controls spanning a relatively large surface area. The user must often reach out of a neutral posture in order to operate many of those controls. This type of reach issue concerns something we call the functional arm reach, the maximum area that a person can reach from a given posture and still successfully perform a manual task - in this case controlling the various equipment on the employee’s desk unit (McCormick & Sanders, 1993). Barnes (1963) also makes a distinction between Normal Reach Area and Maximum Reach Area (figure 5). Normal Reach Area is the area that can conveniently be reached simply by extending the forearms while the upper arms and shoulder remain in a neutral posture at the side of the body, while Maximum Reach Area
Figure 4 | Picture of Arm Position of Worker
Figure 5 | Barnes Graph Cornell Police Communications Center: Ergonomic Analysis and Evaluation
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h: 2’ 41/2”
4’0”
h: 3’9”
6’0”
2’6” 7.5”
2’0”
1’ 2 1/2”
h: 2’ 41/2”
h: adjust. h: adjust.
The other frequent issue observed with the positioning of the arms was that the elbow was often at a height either lower or higher than the hand, bringing the forearm and wrist out of alignment through creating an angled versus neutral arm. This angle occurs because many of the employees are seated at a less than optimal height. The optimal and most neutral posture would allow elbows to remain roughly at 90 degrees, allowing the forearm and wrist to maintain straight alignment (McCormick & Sanders, 1993). The current chair-to-desk relationship causes a discrepency in elbow and wrist height, thus putting the lower arms at an angle. While the work-surface is height adjustable, this trend was seen in several of the recorded postures, and thus requires attention.
8’0”
is the area that can be reached when the arm is extended from the shoulder (McCormick & Sanders, 1993). As illustrated in figure 5, Barnes proposes the normal reach area to span a lateral distance of 47 inches and a depth of 15.5 inches. He proposes the maximum reach area to span a lateral distance of about 59 inches and a depth of 20 inches. While the work surface immediately in front of the employee currently fits the normal reach area at a span of 39 inches and 15” deep, the other areas of the work unit which hold very frequently-used equipment span well beyond even the maximum reach area standards. The units expanding to the side of the desk, which hold additional equipment that the user must control as frequently as the equipment directly in front of them, ranges from an additional 24 to 48 inch lateral span, depending on the unit (figure 6). This reaching action was also observed to increase torso-twisting, which also contributed to elevated scores due to the fact that the torso is twisted out of a neutral alignment (figure 7).
2’6”
Results
Figure 6 | Workstation Dimensions
Legs: In many cases the legs were not adequately supported, either curling under the seat to rest upon the chair’s base, or sprawling out to the side (figures 8 & 9). Interestingly, postures with poorly supported legs were most often observed paired with neutrally-postured arms. This
Results phenomenon may occur due to the fact that employees try to compensate for a non-optimal desk height by raising or lowering their seat height. While the employee may attain a neutral arm posture with the work surface roughly at elbow height, this adjusted seat height may either leave the legs dangling if it is too high, or compressed and curled out to the side if the chair is too low.
Communications Interviews Figure 7 | Reaching Action
Figures 8 & 9 | Leg Placements
Employees spend a lot of shift time talking to their co-workers and reported that communication makes the down time less boring. The majority of the issues with communication relate to the need to communicate while one employee is on the phone and needs the other employee to help them. Interviews found they use hand movements when on the phone to alert the co-worker they need something, and also snap their fingers to alert the other person. Employees said they watch their co-workers’ body language when they are on the phone to know if they need something. They indicated that the arms, hands, and the face of their coworker need to be visible from their station. Not only do they need to be able to see them, but also to hear them, from a quiet finger snap to grab attention, to hearing a co-workers’ phone call, to reading off a monitor to the other person. A couple of people responded that it is occasionally difficult to get someone’s attention as the desks are not facing one another.
Observation
Lack of visual access: We observed that employees
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Results collaborate with each other on both task-oriented and social activities. The responses from the interviews also indicate that the employees talk to co-workers and that body language such as snapping fingers is used regularly as an alternative way to communicate when one is on the phone. This is in line with what Heath and Luff observed in London Underground line control rooms where employees achieved perfect coordination by being able to monitor each other’s activity while also engaged in one’s own (Heath & Luff, 1992). The current arrangement of the desks may not be optimal for channeling visual access since the persons sitting at the two desks (Desk A and B in Figure 1) away from the entrance face opposite corners of the room and away from the person at Desk C (Figure 1) closer to the entrance. In addition, all three persons sit turned away from the entrance and thus cannot naturally see people at the entrance right away. Even though the surveillance cameras and door lock system allow employees to see who is approaching the room and control access accordingly, providing natural visual access to the door area would be helpful since many individuals, other than the employees who are working the current shift, enter the room.
Ambient Conditions Interviews
Interview respondents consistently reported the inadequacies with the lighting in the room. Many people said they frequently suffered from strained and watery eyes and that it was often difficult to read the screen because of the glare from the overhead lights. To counter this, one employee reported setting the background of their screen to a very dark color to make the glare less intense. Other responses to the 14
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lighting included an employee who turns off the lights and works in the dark during the night shift. One employee said they would like to be able to adjust the light level in the room and have a seperate light to adjust at their desk. Another expressed a desire to change the lighting from the ceiling to the floor. Aside from the lighting, another issue with the environment and conditions of the room is that the room feels dry and multiple employees had been given static shocks from the equipment as a result of this.
Observations
Lighting: When one of the students from the observation group visited the control center during a night shift, she noticed that the employee was sitting in the dark. The employee turned on the lights for the observer. As this incident and the interview data show, the general consensus is that the quality of lighting is not optimal. The lighting is harsh on the eyes of employees that have to monitor multiple screens. Lack of task lighting makes it difficult for employees to read documents with small fonts as well.
Analysis and Solutions After analyzing the equipment, communication patterns, and environmental conditions such as lighting and acoustics with a variety of instruments, we have established some design recommendations that would answer many of the found issues. For the sake of feasibility, as we understand that monetary constraints must be taken into account, we have divided our solutions into short-term solutions and longterm solutions. Short-term solutions, in this case, are cheaper and easier to implement as soon as possible whereas longterm solutions are more expensive and entail more difficult installations.
Short-term Solutions: - magnetic or bulletin board
Short-term One of the issues that we had noted during data collection was an abundance of notes around workstation desks. Since these notes seem to be so widely used but are currently not organized, we suggest providing an area close to the center monitor of each workstation for posting notes. One possibility could be a magnetic or bulletin board, or alternatively clip note holders that may be attached and detached to monitors. A clip note holder of this nature would allow employees to clip documents next to the monitor if he or she needs to type from them, as well as providing a place for important notes to stay in sight. We were told that a new computer phone system had been implemented. Employees currently use wired headsets to make and answer calls, however, the interview data shows that some employees experience discomfort with the headsets. A headset with an ergonomic design is recommended (depending on price: short-term or long-term) Bone-conduction headsets are more expensive but offer higher voice quality in noisy
- clip note holders Figure 10 | Plantronics Wireless Headset
environments. They are more sanitary and potentially safer because they do not touch the ear canal. That avoids spreading infection and prevents hearing loss by not irritating ear follicles. The Vonia sets also have flip-up pads that cover the ears and deflect 30% of outside noise (Read, 2005). Plantronics offers a line of wireless headsets which can be integrated into the current phone and radio system (figure 10). Another equipment issue was that employees had an overwhelming number of input devices to interface with multiple computer systems. Some employees reported that sometimes they had trouble remembering which mouse went with which computer. A short-term solution to the problem of confusing which mouse and keyboard go with which computer and monitor is to color code the hardware. For example, put a green marker on the mouse, keyboard, Cornell Police Communications Center: Ergonomic Analysis and Evaluation
- wireless headsets - color coding of hardware - individual compartments - longer cords for equipment - foot-rests
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Analysis and Solutions and monitor that go together. It would be ideal to condense the number of pieces of equipment and minimize functional reach distance. It was also noted that many of the products in the control room are shared. The employees have limited opportunities to personalize their workspace. It was also observed that the plastic folder compartments currently placed on the wall near the entrance for the employees were not being used fully. To resolve these two issues, we suggest installing individual, private/semi-private compartments (e.g. cabinets and lockers) to provide both more storage room and opportunities for personalization. It is still important for natural visual access to occur between employees which may be achieved by altering the layout or seating configuration. Several simple solutions can be implemented to increase the comfort level of the work environment. The results from the RULA analysis indicated that small alterations could be made to the workspace and seating in order to minimize the chance of injury. First, the current desks have a function where users may adjust the desks to their proper height and program that height in for later use. Making use of this function would allow multiple people to sit at the same desks over different shifts but have the desk fit to their body correctly, but as discovered through interviews, the short lengths of the cords connecting the equipment to the power source prevent the employees from using the height-adjustability functions. Simply investing in longer cords for these pieces of equipment so as to allow the desk height to rise would let employees to use the desks for standing and sitting heights, whichever they prefer. Along 16
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with this, educating users on the benefits of and correct ways of adjusting these work stations would be a cost-efficient means of providing employees with comfortable work environments. The work stations currently employed in the call center are not terrible from an ergonomic standpoint in the fact that they are adjustable. The feature of adjustability, however, must be properly put to use in order for it to be effectively helpful. Secondly, it would help to manage the wires around the desk so that this type of movement is not a problem. Proper desk height will allow relaxed arms and 90 degree elbows. As Sanders suggests, “The work surface should be at least elbow height,” and this can be achieved through the desk height programming function (p 435). While programming desks to be the proper height is important, it is equally important that employees sit with their legs supported and feet flat on the ground. This can be achieved by buying foot rests to work for specific employees and by adjusting chair heights. Also important is the action of taking breaks from repetition and static positions, even if those breaks are just taking a walk around the room every so often.
Long-term One interviewee referenced the term “musical chairs” in describing the way the employees go about finding the most comfortable seating position at the beginning of a shift. While the chairs are all different from one another, it was observed that some employees prefer particular chairs over others. Exhibited in this game of swapping chairs, it can be seen that the chairs are not universally designed or adjustable
Analysis and Solutions - and thus are very uncomfortable for many employees. Investing in adjustable chairs and educating people in the correct way of adjusting them to their own body will allow standardization in purchasing and aesthetic, and will cut the amount of time getting comfortable and increase the amount of time dedicated to work. Many adjustable chairs can be overly confusing, offering the user so many bells and whistles that they end up becoming overwhelmed and do not use them at all. Enter, dynamic seat design, which offers users fewer manual adjustments and more automatic adjustments which are built into the chair’s design (McCormick & Sanders, 1993). When the user moves in her or his chair, for instance, the back automatically adjusts with their posture. Automatic adjustment like this can also be created with the use of more flexible materials, such as mesh. A wonderful example of this dynamic technology is Humanscale’s Freedom Task Chair which features a self-adjusting recline, synchronized armrests, and a dynamic headrest (figures 11 & 12). Features like this create adequate support in all postures, following the user’s every move (figure 1). Other possible options for chairs include products by Herman Miller and Steelcase. We observed that many employees rolled their chairs while still sitting in the chairs to move about in the control room. Based on this learning, we recommend that carpet on the floor be replaced with a sustainable hard surface floor covering more suitable for chair-sliding. Some of the materials used for hard surface flooring include bamboo, cork, reclaimed wood, terrazzo, linoleum, wood fiberboard and particleboard, brick and stone, recycled glass and ceramic tile. These are also known for strength and durability and low-
Long-term Solutions: - new adjustable chairs Figures 11 & 12 | Humanscale Freedom Task Chair
maintenance (Gilmore, DEA 303 Lecture on Sept 19, 2007). Because much of the software running on the call center computers, such as the dispatch and new phone system, require separate standalone machines, integrating computer systems is not currently an option. To reduce the number of mice and keyboards at each workstation we recommend a KVM (keyboard, video, mouse) switch that allows the use of one mouse and one keyboard to multiple computers. A product such as the IOGear 8 port DVI USB switch allows up to eight computers be connected to the same keyboard and mouse (figure 13). Reducing the number of input devices would serve a dual purpose. Employees’ efficiency would increase as they would no longer need to spend time thinking about which mouse and keyboard go with which screen. Secondly, there would be significantly more desk space for employees to use and clutter would be greatly reduced. Cornell Police Communications Center: Ergonomic Analysis and Evaluation
- hard surface flooring - KVM switches - lensed indirect uplighting system - reduced flicker lighting - task lighting - raised flooring - new configuration of layout
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Analysis and Solutions With regards to the lighting condition, we suggest a two-component system that consists of indirect and task lighting. Even though direct lighting has the advantage of low cost, it creates harsh shadows and reflected glare whereas
indirect lighting is associated with less direct glare and reflected glare. A study done by researchers at Cornell to determine whether the selection of a parabolic downlighting system or a lensed indirect uplighting system would make a difference in the visual comfort, satisfaction, health or productivity of computer workers showed that the lensed indirect uplighting system was favorable to work productivity and satisfaction (Hedge, Sims and Becker, 1995). Reduced flicker light is also recommended as shown in a study comparing fluorescent lighting, headaches, and eyestrain. One group of participants was exposed to conventional fluorescent light in their office and another group was exposed to light that had reduced flicker because of high-frequency electronic ballasts. After the conditions for the groups were switched, the group that switched from conventional light to low-flicker light reported that the incidence of headaches and eyestrain were reduced by one half of what they were before the switch (Wilkins 1989, Allie). Other long term improvements would include expanding the current workspace and implementing an open work area surrounded by four corner desks in the corners of the room and additional desks along the walls. There is a lot of unused space in the office such as the third large desk in the back office. The current office space can be better utilized by eliminating the wall which divides the front of the office from the back of the office. The manager’s office can also be integrated into the single room which would allow for better communication. Raised flooring with access tiling is another component that would reduce clutter and allow for better cable management.
Figure 13 | IOGear 8 Port DVI USB Switch 18
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Acknowledgments Alexandra, Eunice, Austin, Brooke, and Samantha would like to thank Tom van Haaren and all the employees of the Cornell Police Communications Center for your cooperation and assistance with this project. We hope that this document has oered some useful suggestions and that your workspace will beneďŹ t as a result. We would also like to thank the other students in DEA 470 for assistance in data collection and analysis. And of course, Alan Hedge and Alisha Belk for their help and guidance throughout this process.
Thank You!
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References Allie, Paul. “Establishing an Ergonomically Correct Call Center.” Steelcase. Barnes, R.M. Motion and time study. (5th ed.). New York: Wiley, 1963. “One Size Does Not Fit All.” Call Center Magazine, 19.8 (2006): 33. Dawson, Keith. “Facilities and Design.” The Call Center Handbook, 4th ed. New York: CMP Books, 2001. “E-tools: Computer Workstations: Monitors.” OSHA. <http://www.osha.gov/SLTC/etools/computerworkstations/components_ monitors.html>. Gilmore, R. Lecture presented in DEA 303. Cornell University, Ithaca, NY. 17 September 2007. Heath, C. and Luff, P. “Collaboration and control: Crisis management and multimedia technology in London Underground line control rooms.” Computer Supported Cooperative Work 1.1 (1992): 24-48. Hedge A, WR Sims, and FD Becker. “Effects of lensed-indirect and parabolic lighting on satisfaction, visual health, and productivity of office workers.” Ergonomics 38.2 (1995): 260-280. Hedge, Alan. “Effects of an electric height-adjustable worksurface on self-assessed musculoskeletal discomfort and productivity in computer workers.” Proceedings of the Human Factors and Ergonomics Society 48th Annual Meeting. Santa Monica, CA. 2004. HFES. Hersch, Warren S. “Designs for Better Living (and working).” Call Center Magazine 16.3 (2003): 6. McCormick, E.J. and Sanders, M.S. Human factors in engineering and design. 7th ed. McGraw-Hill, 1993 Read, Brendan. “Ergonomics: Rx for Call Centers.” Call Center Magazine 14.5 (2001): 54-62. Read, Brendan. “Home Sweet Call Center.” Call Center Magazine 18.8 (2005): 34-39. Wilkins, A.J. “Fluorescent Lighting, headaches and eyestrain.” Lighting Research and Technology 21 (1989): 11-18. Cornell Police Communications Center: Ergonomic Analysis and Evaluation
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References Zeisel, J. Inquiry by Design: Environment/Behavior/Neuroscience in Architecture, Interiors, Landscape and Planning. New York: Norton, 2006.
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Appendix A RULA Employee Assessment Worksheet
Complete this worksheet following the step-by-step procedure below.
Keep a copy in the employee's personnel folder for future reference.
A. Arm & Wrist Analysis Step 1: Locate Upper Arm Position +1
-20o
+2
to +20o
> -20
o
Table A
+21o to 45o
+4
+3
+2
Upper
Lower
Arm
Arm
90 o +
+46o to 90o
Step 1a: Adjust…
1
If shoulder is raised: +1; If upper arm is abducted: +1; If arm is supported or person is leaning: -1
Final Upper Arm Score =
Step 2: Locate LowerArm Position +2
+1
-60o
to 100o
+1
+1
+1
0-60
3
Step 2a: Adjust…
Final Lower Arm Score =
4
Step 3: Locate Wrist Position 16o+ +3
0o
+2
+1
0o to 15o +2
0o to 15o
+1
+3 16o+
5
Step 3a: Adjust…
If wrist is bent from the midline: +1
Final Wrist Score =
Step 4: Wrist Twist
If wrist is twisted mainly in mid-range =1; If twist at or near end of twisting range = 2 Use values from steps 1,2,3 & 4 to locate Posture Score in table A
Posture Score A =
Step 6: Add Muscle Use Score
If posture mainly static (i.e. held for longer than 1 minute) or; Muscle Use If action repeatedly occurs 4 times per minute or more: +1
Score =
Step 7: Add Force/load Score
load less than 2 kg (intermittent): +0; 2 kg to 10 kg (intermittent): +1; 2 kg to 10 kg (static or repeated): +2; more than 10 kg load or repeated or shocks: +3
Step 8: Find Row in Table C
The completed score from the Arm/wrist analysis is used to find the row on Table C
6
11o to 20o
+1
1
2
3
4
Wrist twist
Wrist twist
Wrist twist
1
2
1
2
1
2
1
2
1
2
2
2
2
3
3
3
2
2
2
2
2
3
3
3
3
3
2
3
3
3
3
3
4
4
1
2
3
3
3
3
4
4
4
2
3
3
3
3
3
4
4
4
3
3
4
4
4
4
4
5
5
1
3
3
4
4
4
4
5
5
2
3
4
4
4
4
4
5
5
3
4
4
4
4
4
5
5
5
1
4
4
4
4
4
5
5
5
2
4
4
4
4
4
5
5
5
3
4
4
4
5
5
5
6
6
1
5
5
5
6
6
6
6
7
2
5
6
6
6
6
7
7
7
3
6
6
6
7
7
7
7
8
1
7
7
7
7
7
8
8
9
2
8
8
8
8
8
9
9
9
3
9
9
9
9
9
9
9
9
Force/load
Score =
Final Wrist & Arm Score =
+ + =
2
1
1
2
2
3
3
4 5 6
Table C 3
4
5
6
7+
2
3
3
4
5
5
2
3
4
4
5
5
3
3
4
4
5
6
3
3
3
4
5
6
6
4
4
4
5
6
7
7
in extension +4
4
4
5
6
6
7
7
7
5
5
6
6
7
7
7
8+
5
5
6
7
7
7
7
Step 9a: Adjust…
=Final Neck Score
1 also if trunk is well supported while seated; 2 if not
If neck is twisted: +1; If neck is side-bending: +1
0o to 20o
0o to 10o
Step 10: Locate Trunk Position 20o to 60o
+1 standing erect
+3
+2
60 o +
seated - 20o
+4
Step 10a: Adjust…
If trunk is twisted: +1; If trunk is side-bending: +1
= Final Trunk Score
Step 11: Legs
If legs & feet supported and balanced: +1; If not: +2
= Final LegScore
Trunk Posture Score
Table B
+ + =
Final Score= Subject: Company:
Step 9: Locate Neck Position
+3
Wrist
Wrist twist
1
20 o +
+2
Wrist Twist Score =
Step 5: Look-up Posture Score in Table A
If If If If
2
1 0 0 o+
If arm is working across midline of the body: +1; If arm out to side of body: +1
+1
+1
1
+2 o
B. Neck, Trunk & Leg Analysis
0o to 10o
SCORES
1
2
3
4
5
6
L e gs
L eg s
L e gs
L eg s
L e gs
Le g s
Ne c k
1
2
1
2
1
2
1
2
1
2
1
1
1
3
2
3
3
4
5
5
6
6
7
2 7
2
2
3
2
3
4
5
5
5
6
7
7
7
3
3
3
3
4
4
5
5
6
6
7
7
7
4
5
5
5
6
6
7
7
7
7
7
8
8
5
7
7
7
7
7
8
8
8
8
8
8
8
6
8
8
8
8
8
8
8
9
9
9
9
9
Step 12: Look-up Posture Score in Table B = Posture B Score
Use values from steps 8,9,& 10 to locate Posture Score in Table B
Step 13: Add Muscle Use Score If posture mainly static or; If action 4/minute or more: +1
= Muscle Use Score
= Force/load
Score
If If If If
Step 14: Add Force/load Score
load less than 2 kg (intermittent): +0; 2 kg to 10 kg (intermittent): +1; 2 kg to 10 kg (static or repeated): +2; more than 10 kg load or repeated or shocks: +3
Step 15: Find Column in Table C
The completed score from the Neck/Trunk & Leg = Final Neck, Trunk & Leg Score analysis is used to find the column on Chart C
Date: / / Department:
Scorer:
FINAL SCORE: 1 or 2 = Acceptable; 3 or 4 investigate further; 5 or 6 investigate further and change soon; 7 investigate and change immediately © Professor Alan Hedge, Cornell University. Feb. 2001
Cornell Police Communications Center: Ergonomic Analysis and Evaluation
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