1、BS 7273-3:2008Code of practice for the operation of fire protection measures Part 3: Electrical actuation of pre-action watermist and sprinkler systemsICS 13.220.20NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDPublishing and copyright informationThe BSI copyri
2、ght notice displayed in this document indicates when the document was last issued. BSI 2008ISBN 978 0 580 58175 5The following BSI references relate to the work on this standard:Committee reference FSH/12/4Draft for comment 07/30160342 DCPublication historyFirst published October 2000Second edition,
3、 January 2008Amendments issued since publicationAmd. no. Date Text affectedBS 7273-3:2008 BSI 2008 iBS 7273-3:2008ContentsForeword iiiIntroduction 11 Scope 32 Normative references 33 Terms and definitions 44 System design 55 System interface 96 Power supplies, cables and wiring 127 Commissioning and
4、 handover 13AnnexesAnnex A (informative) Example of an arrangement for c.i.e. with separate e.c.d. 14Annex B (informative) Example of an arrangement for c.i.e. with combined e.c.d. 15Annex C (informative) Example of an arrangement for any coincidence logic provided within the c.i.e. 16Annex D (infor
5、mative) Example of an arrangement for any coincidence logic provided within the e.c.d. 17Bibliography 18List of figuresFigure 1 Typical logic gate depiction of pre-action systems 2Figure A.1 Example of an arrangement for c.i.e. with separate e.c.d. 14Figure B.1 Example of an arrangement for c.i.e. w
6、ith combined e.c.d. 15Figure C.1 Example of an arrangement for any coincidence logic provided within the c.i.e. 16Figure D.1 Example of an arrangement for any coincidence logic provided within the e.c.d. 17List of tablesTable 1 Maximum areas of coverage per point-type smoke detector to operate pre-a
7、ction watermist and sprinkler systems in still air conditions 7Summary of pagesThis document comprises a front cover, an inside front cover, pages i to iv, pages 1 to 18, an inside back cover and a back cover.BS 7273-3:2008ii BSI 2008 This page deliberately left blank BSI 2008 iiiBS 7273-3:2008Forew
8、ordPublishing informationThis part of BS 7273 is published by BSI and came into effect on 31 January 2008. It was prepared by Subcommittee FSH/12/4, Automatic operation of fire protection, under the authority of Technical Committee FSH/12, Fire detection and alarm systems. A list of organizations re
9、presented on this committee can be obtained on request to its secretary.SupersessionThis part of BS 7273 supersedes BS 7273-3:2000, which is withdrawn.Relationship with other publicationsBS 7273 is published in a series of parts:Part 1: Electrical actuation of gaseous total flooding extinguishing sy
10、stems;Part 2: Mechanical actuation of gaseous total flooding and local application extinguishing systems;Part 3: Electrical actuation of pre-action watermist and sprinkler systems;Part 4: Actuation of release mechanisms for doors;Part 5: Electrical actuation of watermist systems.Parts 1 and 2 give r
11、ecommendations for the electrical and mechanical actuation of gaseous fire extinguishing systems respectively. Part 4 gives recommendations for the actuation of release mechanisms for doors. Part 5 provides recommendations for electrical actuation of watermist systems (other than pre-action watermis
12、t systems). This current part of BS 7273 provides recommendations for the electrical actuation of pre-action watermist and sprinkler systems.Recommendations for the design, installation, commissioning and maintenance of fire detection and fire alarm systems are given in BS 5839-1. Recommendations fo
13、r the design, installation, commissioning and maintenance of sprinkler systems are given in BS EN 12845. Recommendations for the design, installation, commissioning and maintenance of watermist systems will be given in DD 8489-1, which is currently in preparation. It is anticipated that an amendment
14、 will be issued to BS 7273-3 when DD 8489-1 is published.Information about this documentThis is a full revision of BS 7273-3. The principal changes from the previous edition are as follows. The scope of the standard now includes pre-action watermist systems. References have been updated. Terminology
15、 has been brought into line with related standards, particularly in relation to control and indicating equipment. Reference is made to DD 8489-1 and BS EN 12845.BS 7273-3:2008iv BSI 2008Use of this documentAs a code of practice, this part of BS 7273 takes the form of guidance and recommendations. It
16、 should not be quoted as if it were a specification and particular care should be taken to ensure that claims of compliance are not misleading.Any user claiming compliance with this British Standard is expected to be able to justify any course of action that deviates from its recommendations.Hazard
17、warningsPresentational conventionsThe provisions in this standard are presented in roman (i.e. upright) type. Its recommendations are expressed in sentences in which the principal auxiliary verb is “should”.Commentary, explanation and general informative material is presented in smaller, italic type
18、, and does not constitute a normative element.Contractual and legal considerationsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligation
19、s.CAUTION. Certain electromagnetic fields, such as those generated by radio frequency transmitters, could potentially trigger the charging of pre-action watermist and sprinkler systems or cause them to malfunction. In such cases it is appropriate to take action to minimize the risk of unintentional
20、charging of the pipework due to the electromagnetic field radiated by such apparatus. It might be necessary to seek specialist advice. BSI 2008 1BS 7273-3:2008IntroductionA pre-action sprinkler system is a fire extinguishing system which consists of a sprinkler system and an electrical detection sys
21、tem with water held back by the pre-action valve and pressurized air in the sprinkler pipework. In the event of the operation of the electrical detection system, the pre-action alarm valve operates and allows water into the sprinkler pipework. Pre-action watermist systems work on the same principle.
22、Two generic forms of operation exist: type A and type B.In the case of a type A pre-action system, water will only enter the pipework following the operation of the detection system. Accordingly, type A pre-action systems will only discharge water onto the seat of the fire when both the electrical d
23、etection system and any automatic sprinkler head or watermist nozzle has operated. Any accidental damage to the sprinklers/watermist nozzles, or pipework, will not cause water to be discharged.Type A systems are, therefore, suitable for use in situations in which: there is high potential for mechani
24、cal damage to the system; or the probability of mechanical damage might not be high, but the consequences of inadvertent water damage would include serious damage to sensitive contents and/or major interruption to business.Type B pre-action systems will discharge water onto the seat of a fire when a
25、ny sprinkler or watermist nozzle operates, whether or not the electrical detection system has operated. However, normally the fire detection system will operate before a sprinkler head or watermist nozzle so that, in effect, the system is “wet” at the time of watermist/sprinkler operation. Type B sy
26、stems are normally used in circumstances in which there is a need to speed up the operation of a dry system.The functions of the two systems can be depicted by the binary logic sequence using “and” and “or” gates as given in Figure 1.It is of importance that fire detection systems and any interfaces
27、 associated with pre-action watermist and sprinkler systems have high integrity and do not cause the pre-action alarm valve to remain closed under fire conditions.It is also important to avoid inadvertent operation of the pre-action alarm valve, as draining down of the system can be time consuming a
28、nd inconvenient.The recommendations in this part of BS 7273 take these factors into account, as well as the recommendations of the relevant British and European Standards covering fire detection and fire alarm systems (BS 5839 and BS EN 54) and sprinklers (BS EN 12845). The standard for watermist sy
29、stems has not yet been published, and is expected to be issued as a Draft for Development (DD 8489) in due course. The recommendations relating to watermist in this part of BS 7273 have been developed in liaison with FSH/18, the committee working on DD 8489.BS 7273-3:20082 BSI 2008In some applicatio
30、ns (e.g. cold stores), the consequences of inadvertent discharge are so severe that “double interlocked” pre-action systems are sometimes used. In these systems, water is only allowed to enter the pipework if both the electrical detection system and an automatic sprinkler head/watermist nozzle have
31、operated. This differs from a type A system in that the system remains dry if only the electrical detection system has operated.These and certain other types of pre-action system such as recycling systems are not covered in BS EN 12845 or DD 8489 and are not addressed in this British Standard.Figure
32、 1 Typical logic gate depiction of pre-action systemsDETECTIONACTIVATESPIPEWORK CHARGESANDTYPE BWATERDISCHARGEANDTYPE AWATERDISCHARGEORPIPEWORK CHARGESSPRINKLERHEAD/WATERMISTNOZZLEOPENS BSI 2008 3BS 7273-3:20081 ScopeThis part of BS 7273 gives recommendations for the design, installation and commiss
33、ioning of electrical actuation arrangements for pre-action watermist and sprinkler systems. It covers the interface between fire detection and fire alarm systems (see BS 5839-1), sprinkler systems (see BS EN 12845) and watermist systems1). This part of BS 7273 does not apply to the interface with sp
34、rinkler systems designed in accordance with BS 9251.Recommendations relating to watermist systems which do not operate in the pre-action mode are contained in BS 7273-5.NOTE Watermist systems can be used for the suppression, control and extinguishing of fires. In this part of BS 7273, the references
35、 to fire extinguishing systems relate to watermist systems of any type, as well as to sprinkler systems.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the l
36、atest edition of the referenced document (including any amendments) applies.BS 5839-1:2002, Fire detection and fire alarm systems for buildings Part 1: Code of practice for design, installation, commissioning, and maintenanceBS 6266, Code of practice for fire protection for electronic equipment inst
37、allationsBS EN 54-2, Fire detection and fire alarm systems Part 2: Control and indicating equipmentBS EN 54-4, Fire detection and fire alarm systems Part 4: Power supply equipmentBS EN 12094-1, Fixed firefighting systems Components for gas extinguishing systems Part 1: Requirements and test methods
38、for electrical automatic control and delay devicesBS EN 12094-3, Fixed firefighting systems Components for gas extinguishing systems Part 3: Requirements and test methods for manual triggering and stop devicesBS EN 12845, Fixed firefighting systems Automatic sprinkler systems Design, installation an
39、d maintenanceBS EN 60651, Specification for sound level meters1)Watermist systems will be covered in DD 8489-1, which is currently in preparation.BS 7273-3:20084 BSI 20083 Terms and definitionsFor the purposes of this part of BS 7273, the terms and definitions given in BS 5839-1, BS EN 12845, BS EN
40、12094-1 and the following apply.3.1 coincidencearrangement designed so that an output is obtained only when at least two independent input triggering signals are present at the same timeNOTE For example, an output suitable for triggering a fire extinguishing system is obtained only after a detector
41、has detected a fire, and at least one other independent detector covering the same protected space or hazard has confirmed the existence of fire.3.2 electrical automatic control and delay device (e.c.d.)device that carries out all processing of the functions necessary for the electrical control of a
42、 fire extinguishing systemNOTE The e.c.d. can be either a separate device or part of the control and indicating equipment (c.i.e.) of an automatic fire detection and fire alarm system.3.3 protected spacespace protected by a fire extinguishing systemNOTE Watermist systems used for protection of an ar
43、ea, as opposed to a specific item of equipment or plant, are described as volume protection watermist systems.3.4 pre-actiondry, alternate in dry mode, watermist or sprinkler system in which the alarm valve can be opened by an independent fire detection and fire alarm system in the protected space3.
44、5 stakeholderparty with an interest in the systemNOTE The interest might be: financial, e.g. owner or insurance company; as a customer (internal or external); as an enforcing authority, e.g. building control officer, fire and rescue authority; in a professional capacity as an adviser to one of the p
45、arties, e.g. architect, fire engineer, building service engineer; or in a contractual capacity, e.g. a manufacturer, installer or maintainer of equipment. BSI 2008 5BS 7273-3:20084System design4.1 GeneralThe pre-action mode of operation introduces additional complexity over and above the relatively
46、simple mechanical engineering associated with standard, closed nozzle/head watermist/sprinkler systems. Therefore, it is essential that reliability is maximized. This requires that additional attention is paid to the design of the system.The requirements of the system should be ascertained by the de
47、signer, by means of consultation with the relevant stakeholders. It is particularly important that the agreement of the stakeholders is obtained before the use of a type A pre-action system is considered.It is essential that, in the event of fire, a pre-planned sequence of actions is taken to ensure
48、 the effective operation of the watermist/sprinkler system (see 4.4). Such necessary actions should be discussed at the design stage and incorporated within the proposed system.The system design should conform to the appropriate provisions of: BS 5839-1, for fire detection and fire alarm systems; BS
49、 EN 12845, for sprinkler systems.NOTE Recommendations for the design and installation of watermist systems will be given in DD 8489-1, which is currently in preparation.On the basis of this consultation, the designer should prepare documents showing details of the design. This may include a simple diagrammatic representation of a sequence of actions leading to the discharge of water.4.2 Zoning of the pre-action systemZoning of pre-action sprinkler systems should be in accordance with the require
