e C PD 7974-1:2019 10 BSl StandardsPublication Committee member copy: Do n Application offiresafetyengineering principles to the design of buildings Part 1: Initiation and development of fire within the enclosure of origin (Sub-system 1) bsi.
PD 7974-1:2019 PUBLISHED DOCUMENT Committee member copy: Do not reproduce Publishing and copyright information The BSI copyright notice displayed in this document indicates when the document was last issued. @ The British Standards Institution 2019 Published by BSI Standards Limited 2019 ISBN 978 0 580 97726 8 ICS 13.220.20; 91.040.01 The following BSI references relate to the work on this document: Committee reference FSH/24 Draft for ment 18/30373549 DC Amendments/corrigenda issued since publication Date Text affected @ THE BRITISH STANDARDS INSTITUTION 2019 ALL RIGHTS RESERVED
PUBLISHED DOCUMENT PD 7974-1:2019 e c Contents Page d Foreword i Introduction 1 0 Scope 1 2 Normative references 1 3 Terms definitions and symbols 2 4 Design approach 6 e 4.1 Uncertainty 6 r 4.2 Competence 6 4.3 Framework 6 4.4 Design assessment and basis of design fire selection 7 4.5 Building characteristics 7 m 4.6 Fuel load characteristics 7 4.7 Environmental influences 8 5 Inputs 0 8 Figure 1 - Sub-system 1 inputs 8 60utputs 8 Figure 2 - Sub-system 1 outputs 9 opy: 7 Classification 9 7.1 General 9 7.2 Ignition 9 7.3 Flame spread 10 0 7.4 Fire growth 10 Figure 3 - Conceptual ilustration of continuous fire growth 10 a 7.5 Fully developed 10 Figure 4 - Fire growth in an uncontrolled room fire 11 r Figure 5 - Illustrotion of a travelling fire and ceiling jet [1] 12 e 7.6 Decay 12 b 7.7 End stage 12 8 Design calculations 13 E 8.1 General concepts/principles 13 8.2 13 e 8.3 Characteristics of flames 14 Table 1 - Empirical correlations 15 8.4 Fire growth 17 Table 2 - Standardized alpha t-squared growth rates 17 Table 3 - C constants for different configurations 18 e 8.5 Fully-developed fires (inclusive of decay) 19 e Figure 6 Two indicative travelling fire arrangements with fire travel path lengths and path widths 23 8.6 Post-flashover fires (inclusive of decay) 24 Figure 7 Exomple gas time-temperature curves for post-flashover fires as α function of opening foctor and fire load density with normal enclosure linings 25 8.7 Nominal timetemperature curves 25 8.8 Production of species 26 8.9 Activation of heat detector devices and automatic fire suppression systems 29 0 8.10 Effect of automatic fire suppression systems on fire conditions 29 Annex A (informative) Reference data THE BRITISH STANDARDS INSTITUTION 2019 - ALL RIGHTS RESERVED 1
PD 7974-1:2019 PUBLISHED DOCUMENT e duc Table A.1 - Convective fractions for different fuels [12] 30 Tabie A2 - Standardized fire growth rates [BS ISO/TR 13387-2] 30 not reprodu Table A.3 Fire growth rates for some discrete fuel assemblies 30 Tabie A.4 - Heat release rates per unit area for different occupancies [41] 31 Tabie A.5 - Fire load density for different occupancies 31 Tabie A.6 - Effective emission co-efficient K for various materials 32 Annex B (informative) Reference data for smoke and toxic gas yields 32 Tabie B.1 - Composition of test materials 32 Table B.2 Toxic gas yields effective heats of bustion and oxygen consumption under well-ventilated and under-ventilated bustion conditions for α range of mon polymeric materials from the PD ISO/TS 19700 tube furnace [34] 33 Table B.3 - Smoke mass conversion factor [56] 34 Tabie B.4 Ranges of carbon monoxide yields smoke particulate yields smoke specific extinction areas and mass optical densities for cellulosics and plastics under well-ventiloted and under- Do ventilated faming bustion 35 Tabie B.5 - Corbon monoxide yields smoke particulate yields smoke specific extinction areas and mass optical densities for well-ventilated bustion from Tewarson [57] and Mulholland [35] 36 Annex C(informative)Example configuration factors copy: Bibliography nember e e Summary of pages This document prises a front cover and inside front cover pages i to iv pages 1 to 41 an inside back cover and a back cover. II THE BRITISH STANDARDS INSTITUTION 2019 - ALL RIGHTS RESERVED
PUBLISHED DOCUMENT PD 7974-1:2019 e c Foreword d oro This part of PD 7974 is published by BSI Standards Limited under licence from The British Standards Institution and came into effect on 31 March 2019. It was prepared by Technical Committee FSH/24 Fire safety engineering. A list of organizations represented on this mittee can be obtained on request to its secretary. e Supersession r This part of PD 7974 supersedes PD 7974-1:2003 which is withdrawn. t Relationship with other publications 0 This Published Document is one of a series of documents published under the Fire Standards Policy m Committee and is a supporting document to BS 7974 Application of fire sofety engineering principles to the design of buidings - Code of practice. 0 Other parts in this series PD 7974 include: D Part 2: Spread of smoke and toxic gases within and beyond the enclosure of origin (Sub-system 2) Part 3: Structural response and fire spreod beyond the enclosure of origin (Sub-system 3) opy: Part 4: Detection of fire and activation of fire protection systems (Sub-system 4) Part 5: Fire and rescue service intervention (Sub-system 5) Part 6: Human foactors: Life sofety strategies Occupant evacuation behaviour and condition 8 (Sub-system 6) c Part 7: Probabilistic risk assessment Information about this document r e This is a full revision of the document and introduces the following principal changes: b consolidation of all principal design fire development considerations into sub-system 1 which are subsequently called upon as an input for other sub-systems (e.g. 2 and 3); m greater clarity regarding the phases of fire development; e • design correlations that logically follow a conventional fire timeline of events; m where practicable explicit acknowledgements of the inherent assumptions underpinning design correlations; •further generalization of design approximations for growing fires; e revised correlations with respect to ignition heat flux from localized fires pre-flashover e partment fire temperatures and sprinkler-controlled fires; •the introduction of a travelling fire framework for fully developed fires that might not develop to flashover E * improved reference data for smoke and toxic gas yields; and removal of some reference data as it is either too generalized or out of date. m Use of this document 0 pnous a suoepuauu pue aouepn8 go uo a saen 6 jo ued s apn e sy not be quoted as ifit were a specification or a code of practice and claims of pliance cannot C be made to it. THE BRITISH STANDARDS INSTITUTION 2019 - ALL RIGHTS RESERVED II1
英文原版 PD 7974-1 2019 消防安全工程原理在建筑设计中的应用 第1部分 火源范围内火灾的起始和发展.pdf
