PUBLISHED DOCUMENT PD 7974-1:2019 e c Contents Page
Foreword i d Introduction1 0Scope1
2Normative references1 3Terms, definitions and symbols2 4Design approach6 e4.1Uncertainty6 r4.2Competence6
4.3Framework6 4.4Design assessment and basis of design fire selection7 4.5Building characteristics7 4.6Fuel load characteristics7 m4.7Environmental influences8
5 Inputs8 0Figure 1 - Sub-system 1 inputs 8 60utputs8 Figure 2 - Sub-system 1 outputs9 7Classification9 7.1General9 opy:7.2Ignition9
7.3Flame spread10 7.4Fire growth10 0Figure 3 - Conceptual ilustration of continuous fire growth10 a7.5Fully developed10
Figure 4 - Fire growth in an uncontrolled room fire11 r Figure 5 - Illustrotion of a travelling fire and ceiling jet [1]12 e7.6Decay12
7.7End stage12 b8 Design calculations13 E8.1General concepts/principles13 8.213 e8.3Characteristics of flames14
Table 1 - Empirical correlations15 8.4Fire growth17 Table 2 - Standardized alpha t-squared growth rates17 Table 3 - C, constants for different configurations18 e8.5Fully-developed fires (inclusive of decay)19 e Figure 6 Two indicative travelling fire arrangements with fire travel path lengths and path widths23 8.6Post-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 linings25 8.7Nominal timetemperature curves25 8.8Production of species26 8.9Activation of heat detector devices and automatic fire suppression systems29 8.10Effect of automatic fire suppression systems on fire conditions29 0Annex 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] Tabie A2 - Standardized fire growth rates [BS ISO/TR 13387-2]3030 Table A.3 Fire growth rates for some discrete fuel assemblies Tabie A.4 - Heat release rates per unit area for different occupancies [41]3130 Tabie A.5 - Fire load density for different occupancies Tabie A.6 - Effective emission co-efficient, K, for various materials3132 Tabie B.1 - Composition of test materials Annex B (informative) Reference data for smoke and toxic gas yields3232 not reprodu 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 Table B.3 - Smoke mass conversion factor [56] materials from the PD ISO/TS 19700 tube furnace [34]3334 areas and mass optical densities for cellulosics and plastics under well-ventiloted and under- Tabie B.4 Ranges of carbon monoxide yields, smoke particulate yields, smoke specific extinction ventilated faming bustion Tabie B.5 - Corbon monoxide yields, smoke particulate yields, smoke specific extinction areas35 Do and mass optical densities for well-ventilated bustion from Tewarson [57] and Mulholland [35] 36 Annex C(informative)Example configuration factors Bibliography copy: 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 Institution, and came into effect on 31 March 2019. It was prepared by Technical Committee FSH/24, This part of PD 7974 is published by BSI Standards Limited, under licence from The British Standards oro 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 0This Published Document is one of a series of documents published under the Fire Standards Policy Committee, and is a supporting document to BS 7974, Application of fire sofety engineering principles m to the design of buidings - Code of practice. 0Other 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) Part 4: Detection of fire and activation of fire protection systems (Sub-system 4) opy: 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 r Information about this document e This is a full revision of the document, and introduces the following principal changes: b are subsequently called upon as an input for other sub-systems (e.g. 2 and 3); consolidation of all principal design fire development considerations into sub-system 1 which m greater clarity regarding the phases of fire development; e• design correlations that logically follow a conventional fire timeline of events; correlations; where practicab...
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
