1、BSI Standards PublicationBS ISO 29903:2012Guidance for comparisonof toxic gas data betweendifferent physical fire modelsand scalesBS ISO 29903:2012 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 29903:2012.The UK participation in its preparation was entrusted
2、to TechnicalCommittee FSH/16, Hazards to life from fire.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The Briti
3、sh Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 74791 5ICS 13.220.01Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2
4、013.Amendments issued since publicationDate Text affectedBS ISO 29903:2012 ISO 2012Guidance for comparison of toxic gas data between different physical fire models and scalesLignes directrices pour la comparaison de donnes de gaz toxiques entre divers modles et chelles de feu physiquesINTERNATIONAL
5、STANDARDISO29903First edition2012-12-01Reference numberISO 29903:2012(E)BS ISO 29903:2012ISO 29903:2012(E)ii ISO 2012 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2012All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by a
6、ny means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCase postale 56 CH-1211 Geneva 20Tel. + 41 22 749 01 11Fax + 41 22 749 09 47E-mail copy
7、rightiso.orgWeb www.iso.orgPublished in SwitzerlandBS ISO 29903:2012ISO 29903:2012(E) ISO 2012 All rights reserved iiiContents PageForeword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 24 Combustion conditions 34.1 General . 34.2 Thermal environment . 34.3 Ventilation
8、 . 34.4 Characteristics of test specimens 35 Toxic gas data . 45.1 Identification of toxic species . 45.2 Different expressions for toxic gas data 45.3 Significance of analysis data 66 Comparison/prediction of toxic gas data from different physical fire models . 76.1 General . 76.2 Comparison princi
9、ples . 86.3 Comparison methodology . 96.4 Prediction of data from one fire model to another .117 Documentation 12Annex A (informative) Characteristics of physical fire models 13Annex B (informative) Influence of sampling and analysis on toxic gas data .16Annex C (informative) Application examples: C
10、omparison of ISO 19700 bench-scale data with data from large-scale tests 18Bibliography .25BS ISO 29903:2012ISO 29903:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Internationa
11、l Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO,
12、also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committ
13、ees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possi
14、bility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 29903 was prepared by Technical Committee ISO/TC 92, Fire Safety, Subcommittee SC 3, Fire threat to people and the environment.iv
15、 ISO 2012 All rights reservedBS ISO 29903:2012ISO 29903:2012(E)IntroductionThe production of toxic gases in fires can be a significant factor in determining whether people escape from a fire or not. Estimation of the time available for escape and the time required for escape each require values of t
16、he concentrations of toxic gases along possible escape paths. Typically, the yields of the gases from burning finished products are estimated or measured prior to conducting such calculations. In some rare cases toxic species production can be calculated during modelling of the fire development. Typ
17、ically spread of the gases and their dilution with air is then simulated using equations or computational models.The yields of these gases can be measured in a real-scale laboratory test of the entire finished product (e.g. a chair) or in a bench-scale test (using a physical fire model) of a specime
18、n cut from the product or a component of the product. Since there are thousands of different combustibles, routine real-scale testing is both costly and impractical. Thus, there is a need to develop reliable methods to use physical fire models, conducted in less than real-scale, for the estimation o
19、f real-scale emissions.The yields of the gases from the real-scale test are often considered to be the accurate values for the particular test conditions. In tests involving a portion of the finished product in a physical fire model, the specimen characteristics and the combustion conditions differ
20、from those in the real-scale test. In most cases the physical fire model reproduces one part of the entire real-scale scenario, e.g. initial well ventilated conditions or later vitiated conditions. The yields of combustion products in a fire test depend on apparatus conditions such as: the fuel/air
21、equivalence ratio, whether the decomposition is flaming or non-flaming, the persistence of flaming of the sample, the temperature of the specimen and the effluents produced, the stability of the decomposition conditions, and the interaction of the apparatus with the decomposition process, with the e
22、ffluents and with the flames.It is, therefore, important to have a standardised methodology for comparing the toxic gas yields generated in tests of different scales to determine the appropriateness of using the data from individual physical fire models in fire hazard and risk assessment. It is also
23、 valuable to be able to compare the yield data from different physical fire models to determine whether or when they generate comparable results.This International Standard concerns the comparison of toxic gas data between small-scale (physical fire models) and large-scale tests and between differen
24、t small-scale tests, i.e. it coversa) the comparison of toxic gas data from fire tests of different physical scales and characteristics in terms of a methodology to identify whether the data are comparable and (provided it is comparable) how to make relevant comparisons, andb) the prediction of larg
25、e-scale results based on small-scale test data or vice versa. ISO 2012 All rights reserved vBS ISO 29903:2012BS ISO 29903:2012Guidance for comparison of toxic gas data between different physical fire models and scales1 ScopeThis International Standard provides principles for characterizing the measu
26、red production of toxic gases from a laboratory fire test and provides bases for comparing the results between different types and scales of such tests. It also includes consideration of the uncertainties in the gas determinations. The combined uncertainty is a key factor in the ability to establish
27、 similarity or difference of test results.The sufficiency of the agreement between a bench-scale test and a real-scale test depends on the precision needed in the fire hazard or risk assessment, which is not covered by ISO 29903:2012.This International Standard defines the relevance and significance
28、 of toxic gas data from measurements in different fire tests. With such a definition it is possible to provide generic guidance on how such data can be compared between different sizes and types of fire tests.The combustion conditions represented by the fire test, other specific characteristics of t
29、he test and the test specimen, the sampling strategy of the fire effluents, and the analysis technique for the toxic gas species are the most important factors when defining the significance of the toxic gas data.This International Standard is intended to serve as a tool for thea) definition of the
30、relevance and significance of toxic gas data from fire tests,b) comparison of toxic gas data from fire tests of different scales and characteristics, andc) prediction of toxic gas data from a large-scale test based on small-scale data or vice versa.This International Standard gives general guidance
31、regarding comparison of toxic gas data between physical fire models of different scales, but is principally developed for the gases listed in ISO 13571, i.e. carbon dioxide (CO2), carbon monoxide (CO), hydrogen halides (HCl, HBr, HF), sulfur dioxide (SO2), hydrogen cyanide (HCN), nitrogen oxides (NO
32、, NO2), formaldehyde (CH2O) and acrolein (C3H4O).This International Standard does not cover characterization and comparisons of the toxicity of the effluents from fire tests.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indisp
33、ensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 5725-1, Accuracy (trueness and precision) of measurement methods and results Part 1: General principles and
34、definitionsISO 13571, Life-threatening components of fire Guidelines for the estimation of time available for escape using fire dataISO 13943, Fire safety VocabularyISO 16730, Fire safety engineering Assessment, verification and validation of calculation methodsISO 19706, Guidelines for assessing th
35、e fire threat to peopleINTERNATIONAL STANDARD ISO 29903:2012(E) ISO 2012 All rights reserved 1BS ISO 29903:2012ISO 29903:2012(E)3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 13943, ISO 5725-1 and the following apply.3.1small-scale fire testfire test
36、 performed on a test specimen of small dimensionsNOTE 1 The definition above is taken from ISO 13943 and is given here for clarity and the convenience of the reader.NOTE 2 Such a test is synonymously referred to as a “bench-scale test.”NOTE 3 In these tests, the typical maximum length of a linear te
37、st specimen is less than 1 m. The typical maximum dimensions of a rectangular specimen are approximately 0.1 m.3.2medium-scale fire testfire test performed on a test specimen of small-medium size dimensionsNOTE A fire test performed on a test specimen of which the maximum dimension is between 0.5 m
38、and 1.0 m is here called a medium-scale fire test.3.3intermediate-scale fire testfire test performed on a test specimen of medium dimensionsNOTE 1 The definition above is taken from ISO 13943 and is given here for clarity and the convenience of the reader.NOTE 2 A fire test performed on a test speci
39、men for which the maximum dimension is between 1 m and 3 m is usually called an intermediate-scale fire test.3.4large-scale fire testfire test, that cannot be carried out in a typical laboratory chamber, performed on a test specimen of large dimensionsNOTE 1 The definition above is taken from ISO 13
40、943 and is given here for clarity and the convenience of the reader.NOTE 2 A fire test performed on a test specimen of which the maximum dimension is greater than 3 m is usually called a large-scale fire test.3.5real-scale fire testfire test that simulates a given application, taking into account th
41、e real scale, the real way the item is installed and used, and the environmentNOTE 1 The definition above is taken from ISO 13943 and is given here for clarity and the convenience of the reader.NOTE 2 Such a fire test normally assumes that the products are used in accordance with the conditions laid
42、 down by the specifier and/or in accordance with normal practice.3.6matrix effectcombined effect of all components of the sample other than the analyte on the measurement of the quantityNOTE 1 Matrix effect (in analytical chemistry) as defined in IUPAC Compendium of Chemical Terminology 1.NOTE 2 The
43、 matrix effect in analysis of toxic gases in a fire effluent will be the combined effect from the components of the effluent on the analyte.NOTE 3 If a specific component can be identified as causing an effect then this is referred to as interference.2 ISO 2012 All rights reservedBS ISO 29903:2012IS
44、O 29903:2012(E)4 Combustion conditions4.1 GeneralThe yields and nature of the fire effluent component from a fire test of any scale are determined by the involved fuels and the prevalent thermal and oxidative conditions in the current stage of the fire. These conditions also determine the burning ra
45、te of the products/materials and thus the rate of effluent generation. See ISO 16312-1.During a fire test of a finished product, the combustion conditions are likely to change. These changes include the chemistry of the combustible item and the sufficiency of the ventilation.Whether decomposition is
46、 flaming or non-flaming is a dominant factor in the production of toxic gases.The combustion conditions under which toxic gas data are developed shall be as close to equivalent as possible between the physical fire models or test scales compared (see Clause 6).NOTE 1 A large change in the rate of co
47、mbustion may affect the degree of oxidation of the emitted effluent. Smaller changes in combustion rate may have no significant effect.NOTE 2 Fire stages and the corresponding combustion conditions are described in ISO 19706.4.2 Thermal environmentThe thermal boundary conditions in a test include th
48、e external applied heat flux and the heat flux from any flaming combustion. Also of importance is the heat flux distribution among radiation, convection, and conduction.The thermal environment sensed by the test specimen during combustion includes both gas temperature and the temperature of the samp
49、le material, as defined by the thermal boundary conditions.4.3 VentilationThe oxygen availability (ventilation) in the physical fire models compared determines the combustion conditions. Comparison among different methods requires characterization of the ventilation conditions in order to assess the degree of similarity.For a given experiment, it is necessary to identify how the ventilation is characterized and whether the characterization is local or global.For a physical fire model in which the fuel gasification rate and the entering oxygen flow and c
copyright@ 2008-2019 麦多课文库（www.mydoc123.com）网站版权所有
备案/许可证编号：苏ICP备17064731号-1