ISO INTERNATIONAL STANDARD 13571 Second edition 2012-09-15 Life-threatening components of fire Guidelinesforthe estimationoftimeto compromisedtenabilityinfires Composantsdangereuxdufeu-Lignesdirectricespour I'estimationdutemps disponibleavantque les conditions de tenabilitenesoientcompromises Reference number ISO13571:2012(E) @ISO 2012 ISO13571:2012(E) COPYRIGHTPROTECTEDDOCUMENT ISO 2012 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO's member body in the country of the requester. ISO copyright office Case postale 56 · CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail [email protected] Web www.iso.org Published in Switzerland ii @ ISO 2012 - All rights reserved ISO13571:2012(E) Contents Page Foreword iv Introduction 1 Scope 2 Normative references 3 Terms and definitions 4 General principles. 4.1 Timetocompromisedtenability 4.2 Toxic-gas model.... 4.3 Mass-loss model.. 4.4 Heat and radiant energy model 4.5 Smoke-obscurationmodel. 4.6 Assumptionsandexclusions 5 Significance and use 6 Toxic-gas models 6.1 Asphyxiant-gas model 6.2 Irritant-gas model 7 Mass-loss model. 8 8 Heat 9 Smoke-obscuration model 10 Report. AnnexA(informative)Contextand mechanismsoftoxicpotency Bibliography 19 @ ISO 2012 -Allrights reserved ili ISO 13571:2012(E) Foreword IsO (the International Organization for Standardization) is a worldwide federation of national standards bodies non-governmental, in liaison with isO, also take part in the work. isO collaborates closely with the International Electrotechnical Commission (IEC) on allmatters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/lEc Directives, Part 2. The main task of technical committees 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. rights. IsO shall not be held responsible for identifying any or all such patent rights. ISO13571waspreparedbyTechnical CommitteeISO/TC92,Firesafety,SubcommitteeSC3,Firethreatto peopleandenvironment. iv @ISO2012-All rights reserved ISO13571:2012(E) Introduction Estimation of occupants'tenability when exposed to afire environment ultimately involves theirabilityto perform continued functioning in place as necessary. The latter situation includes occupants who are not mobile or component of fire safety design. sources, e.g., ISO/TR 13387-8 and ISO/TR 16738 to heat and fire effluent combustion products and their individual susceptibility to such exposures (see A.2.3). The purpose of the methodology described in this International Standard is to provide a framework for use in estimating the time at which compromised tenability may occur. The methodology described cannot be used alone to evaluate the overall fire safety performance of specific quantity and types of combustibles, fuel chemistry) and of the enclosure (e.g.dimensions, ventilation).These determine the toxic-gas concentrations, the gas and wall temperatures and the density of smoke throughout regarding the position of the occupants' heads relative to the hot smoke layer that forms near ceilings and descends as the fire grows. The guidance in this International Standard is based on the best available scientific judgment in using a state- ethical reasons, much of the methodology described has not been and cannot be validated experimentally with cause of fire fatalities, the database is actually quite extensive and well-validated with human experience. As with all predictive methodology, uncertainty exists in the application of this International Standard. An estimation of the uncertainty