BS 5588-4:1998
Introduction The pressure differential systems referred to in this standard are primarily intended for life safety and firefighting purposes with the objective of maintaining tenable conditions in protected escape routes, refuges, firefighting shafts, lobbies, etc. The general principles presented in this standard may also be applied in situations where the primary aim is to prevent contamination by smoke, of goods or equipment in rooms adjacent to a fire-affected space. Guidance is given on the design of systems intended either to maintain a positive pressure within protected spaces (pressurization) or to remove hot gases from the fire zone so as to maintain it at a lower pressure than the adjacent protected space (depressurization). Pressure differential systems provide one means of improving the level of fire safety within a building. A decision as to whether such a system is appropriate to a particular project should be taken in context with the overall design strategy for means of escape, firefighting and property protection within the building. This standard presents the general principles to be adopted in the design of various types of pressure differential system. However, circumstances vary from building to building and it is not possible to cover every situation here, although it may be possible to design an effective system for other applications using the principles of this standard.
1 Scope This part of BS 5588 gives guidance on the design, installation, testing and maintenance in new and existing buildings of systems intended to limit the spread of smoke by means of pressure differentials. However, this standard does not cover smoke ventilation systems used in theatres and other places of assembly which protect the auditorium from a fire in the stage area by creating a pressure differential between the stage and the auditorium.
2 References 2.1 Normative references This part of BS 5588 incorporates, by dated or undated reference, provisions from other publications. These normative references are made at the appropriate places in the text and the cited publications are listed on page 72. For dated references, only the edition cited applies; any subsequent amendments to, or revisions of the cited publication apply to this part of BS 5588 only when incorporated in the reference by amendment or revision. For undated references, the latest edition of the cited publication applies, together with any amendments. 2.2 Informative references This part of BS 5588 refers to other publications that provide information or guidance. Editions of these publications current at the time of issue of this standard are listed on page 73, but reference should be made to the latest editions.
3 Definitions For the purposes of this British Standard the following definitions apply. 3.1 accommodation area area of a building where the main work function of the building is carried out 3.2 air release means by which pressurizing air is able to escape from the accommodation area or other unpressurized space to external air 3.3 atrium space within a building, not necessarily vertically aligned, passing through one or more structural floors NOTE
Enclosed lift wells, escalator wells, building services ducts and stairways are not classified as atria.
Š BSI 8 December 2004
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