1、BS 7273-5:2008Code of practice for the operation of fire protection measures Part 5: Electrical actuation of watermist systems (except pre-action systems)ICS 13.220.20NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDPublishing and copyright informationThe BSI cop
2、yright notice displayed in this document indicates when the document was last issued. BSI 2008ISBN 978 0 580 58176 2The following BSI references relate to the work on this standard:Committee reference FSH/12/4Draft for comment 07/30160345 DCPublication historyFirst published January 2008Amendments i
3、ssued since publicationAmd. no. Date Text affectedBS 7273-5:2008 BSI 2008 iBS 7273-5:2008ContentsForeword iii1 Scope 12 Normative references 13 Terms and definitions 24 System design 35 Fire detection 56 Control and indicating equipment 87 Controls and indications 88 Power supplies, cables and wirin
4、g 119 Commissioning and handover 11AnnexesAnnex A (informative) Typical sequence of actions 13Bibliography 14List of figuresFigure A.1 Diagrammatic representation of a typical sequence of actions leading to the discharge of water from a watermist system 13Summary of pagesThis document comprises a fr
5、ont cover, an inside front cover, pages i to iv, pages 1 to 14, an inside back cover and a back cover.BS 7273-5:2008ii BSI 2008 This page deliberately left blank BSI 2008 iiiBS 7273-5:2008ForewordPublishing informationThis part of BS 7273 is published by BSI and came into effect on 31 January 2008.
6、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 represented on this committee can be obtained on request to its secretary.Relationship with other publication
7、sBS 7273 is published in a series of parts:Part 1: Electrical actuation of gaseous total flooding extinguishing systems;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
8、: Actuation of release mechanisms for doors;Part 5: Electrical actuation of watermist systems.Parts 1 and 2 give recommendations for the electrical and mechanical actuation of gaseous fire extinguishing systems respectively. Part 3 provides recommendations for electrical actuation of pre-action wate
9、rmist and sprinkler systems. Part 4 gives recommendations for the actuation of release mechanisms for doors. This current part of BS 7273 provides recommendations for the electrical actuation of watermist systems (other than pre-action watermist systems).Recommendations for the design, installation,
10、 commissioning and maintenance of fire detection and fire alarm systems are given in BS 5839-1. 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 will be
11、issued to BS 7273-5 when DD 8489-1 is published.Information about this documentThere has been a significant growth in the use of watermist fire protection since the demise of halon gas fire extinguishing agents on environmental grounds. Such systems are now used to protect special hazards such as tu
12、rbines, generators and kitchen ranges. They are also being used for residential applications, such as hotels, for office environments and to protect electrical equipment installations. This part of BS 7273 addresses the interface between the fire detection and fire alarm systems that control watermi
13、st systems, and the mechanical components of such systems.BS 7273-5:2008iv BSI 2008Use of this documentAs a code of practice, this part of BS 7273 takes the form of guidance and recommendations. It should not be quoted as if it were a specification and particular care should be taken to ensure that
14、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 warningsPresentational conventionsThe provisions in this standard are presented in roman (i.e. upright)
15、 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, and does not constitute a normative element.Contractual and legal considerationsThis publication does
16、 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 obligations.CAUTION. Certain electromagnetic fields, such as those generated by radio frequency transmitters, cou
17、ld potentially trigger watermist systems or cause them to malfunction. In such cases it is essential to avoid the risk of accidental discharge due to the electromagnetic field radiated by such apparatus. It might be necessary to seek specialist advice. BSI 2008 1BS 7273-5:20081 ScopeThis part of BS
18、7273 gives recommendations for the design, installation and commissioning of electrical actuation arrangements for watermist systems. It covers the interface between fire detection and fire alarm systems (see BS 5839-1) and watermist systems1).The recommendations are applicable to systems intended e
19、ither for local application or volume protection.Recommendations relating to pre-action watermist systems are contained in BS 7273-3.NOTE Watermist systems can be used for the suppression, control and extinguishing of fires. In this part of BS 7273, the references to watermist systems relate to wate
20、rmist systems of any type.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 latest edition of the referenced document (including any amendments) applies. B
21、S 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 installationsBS EN 54-2, Fire detection and fire alarm systems Part 2: Control an
22、d 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 for electrical automatic control and delay devicesBS EN 12094-3, Fixed firefi
23、ghting systems Components for gas extinguishing systems Part 3: Requirements and test methods for manual triggering and stop devices1)Watermist systems will be covered in DD 8489-1, which is currently in preparation.BS 7273-5:20082 BSI 20083 Terms and definitionsFor the purposes of this part of BS 7
24、273, the terms and definitions given in BS 5839-1, BS EN 12094-1 and the following apply.3.1 automatic/manual and manual only mode switchmeans of converting a system from automatic and manual to manual only actuationNOTE This can be in the form of a manual switch on the e.c.d. or other units, or a p
25、ersonnel door interlock; in all cases, this changes the actuation mode of the system from automatic and manual to manual only or vice versa.3.2 automaticmode of operation in which the system can actuate without manual intervention3.3 coincidencearrangement designed so that an output is obtained only
26、 when at least two independent input triggering signals are present at the same timeNOTE For example, an output suitable for triggering a watermist system is obtained only after a detector has detected a fire, and at least one other independent detector covering the same protected space or hazard ha
27、s confirmed the existence of fire.3.4 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 watermist systemNOTE The e.c.d. can be either a separate device or part of the control and indicating equipmen
28、t (c.i.e.) of an automatic fire detection and fire alarm system.3.5 local application systemwatermist system designed to provide object protection within a larger overall space3.6 manualmode of operation in which the system can actuate only with manual intervention3.7 protected spacespace protected
29、by a watermist systemNOTE Volume protection systems are normally used for such spaces (see 3.12).3.8 protected hazardobject protected by a watermist systemNOTE Local application systems are normally used for such hazards. BSI 2008 3BS 7273-5:20083.9 stakeholderparty with an interest in the systemNOT
30、E 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 parties, e.g. architect, fire engineer, building serv
31、ice engineer; or in a contractual capacity, e.g. a manufacturer, installer or maintainer of equipment.3.10 watermistwater spray for which the Dv0,90measured in a plane 1 m from the nozzle at its minimum operating pressure is less than 1 mmNOTE Dv0,90 is the drop diameter such that the cumulative vol
32、ume, from zero diameter, to the respective diameter, is nine tenths of the corresponding sum of the total distribution.3.11 watermist systemone or more watermist installations connected to a water supplyNOTE Watermist systems can discharge water or a mixture of water and some other agent or agents,
33、i.e. inert gases or additives.3.12 volume protection systemwatermist system designed to protect an enclosed volumetric space4System design4.1 GeneralThe requirements for the protected space or hazard(s) should be ascertained by the designer, by means of consultation with the relevant stakeholders.It
34、 is essential that, in the event of fire, a pre-planned and practised course of action is taken to ensure the effective operation of the watermist system. Such necessary actions should be discussed at the design stage and incorporated within the proposed system.The system design for fire detection a
35、nd fire alarm systems should conform to the appropriate provisions of BS 5839-1.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 det
36、ails of the design. These may include a simple diagrammatic representation of a sequence of actions leading to the discharge of water (see Annex A for an example of diagrammatic representation for a watermist system).BS 7273-5:20084 BSI 20084.2 Operation of the systemOperation of the system should f
37、ollow a sequence leading to the release of water (for example, see Annex A). This sequence may encompass coincidence (see 3.1) in order to avoid unwanted discharges when in the automatic mode of operation.Operation of the first detector should result in at least an indication of fire at the c.i.e. a
38、nd generate an audible fire alarm warning local to the protected space or hazard (see Annex A). As an alternative, or in addition to this, it may also result in the sounding of the buildings fire alarm system.NOTE 1 A further, but different, audible warning (the pre-discharge warning signal) is norm
39、ally required (see 7.1.3). Confirmation of discharge of the watermist system (“released condition”) should be indicated at the e.c.d. by means of a signal representing the flow of water. The method of deriving the signal should be a pressure or flow switch, located so as to indicate that discharge o
40、f water has occurred from any storage container in the system. For example, in the case of a bank of containers, the discharge of water from any container into the central manifold should be indicated.For systems with a shared water supply protecting more than one separate protected space or hazard,
41、 it can be beneficial to indicate separate released conditions for each protected space/hazard. These would be derived from pressure/flow switches located downstream of the control valves. However, a released condition signal should still be derived from upstream of the valves.NOTE 2 This will ensur
42、e that a warning is generated if water is trapped in the system due to a control valve failing to open. Interruption of the connection between the c.i.e. and any part of the e.c.d. should not affect the operation of any fire detector or the generation of the local audible warning (and/or sounding of
43、 the buildings fire alarm system).Conditions that would prevent the correct operation of the system, e.g. low pressure in propellant gas container(s), may be monitored and indicated as an “incorrect status condition” at the e.c.d.The operation of any control for disabling the system during maintenan
44、ce should be monitored and be indicated as a “disabled condition”.Conditions arising from the use of a pumped water supply might need to be monitored. BSI 2008 5BS 7273-5:20084.3 Circuit design4.3.1 Fire detection and fire alarm system The system should be designed so that in the event of a single c
45、able fault the system is still capable of at least manual discharge of water.Where coincidence is used, the system should be designed so that in the event of a single cable fault, at least a degraded form of detecting fire remains. If the system is designed so that the maximum area of coverage per d
46、etector is generally X m2, the degraded level of detection should be such that those detectors that remain operational provide a maximum area of coverage of 2X m2per detector evenly distributed throughout the protected space. The degraded detection should meet at least the spacing and positioning re
47、commendations given in BS 5839-1.The purpose of this degraded detection is to enable warning to be given to persons so that at least manual operation of the extinguishing system is possible.This can be achieved by, for example, using two interleaved circuits or a single circuit provided that it is c
48、onfigured as a loop and has suitable short and open circuit protection.4.3.2 Connection to the watermist systemIf the means for transmission of signals in either direction between the c.i.e. and the e.c.d. is via a non-exclusive circuit, e.g. part of a loop of an addressable system, the connections
49、should be protected against a single cable fault (i.e. both short-circuit and open-circuit) on any part of the circuit, e.g. by the provision of short circuit isolators.4.3.3 Circuits containing detectorsIf detector circuits are common to more than one protected space or hazard, the signal to initiate discharge of water into a protected space (or over the protected hazard) where fire has been detected should not contribute to the discharge of water in another protected space (or over another protected hazard) whose fire de
