BS-EN-60695-6-1-2001 IEC-60695-6-1-2001.pdf

BRITISH STANDARD BS EN 60695-6-1:2001 IEC 60695-6-1:2001 Fire hazard testing Part 6-1: Smoke opacity General guidance The European Standard EN 60695-6-1:2001 has the status of a British Standard ICS 13.220.99; 29.020 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI BS EN 60695-6-1:2001 This British Standard, having been prepared under the direction of the Electrotechnical Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 22 November 2001 © BSI 22 November 2001 ISBN 0 580 38706 2 National foreword This British Standard is the official English language version of EN 60695-6-1:2001. It is identical with IEC 60695-6-1:2001. The UK participation in its preparation was entrusted to Technical Committee GEL/89, Fire hazard testing, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old number. For instance, IEC 27-1 has been renumbered as IEC 60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 30, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI EUROPEAN STANDARDEN 60695-6-1 NORME EUROPÉENNE EUROPÄISCHE NORMOctober 2001 CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels © 2001 CENELEC -All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60695-6-1:2001 E ICS 13.220.99; 29.020 English version Fire hazard testing Part 6-1: Smoke opacity - General guidance (IEC 60695-6-1:2001) Essais relatifs aux risques du feu Partie 6-1: Opacité des fumées - Guide général (CEI 60695-6-1:2001) Prüfungen zur Beurteilung der Brandgefahr Teil 6-1: Verdunkelung durch Rauch - Allgemeiner Leitfaden (IEC 60695-6-1:2001) This European Standard was approved by CENELEC on 2001-10-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Foreword The text of document 89/447/FDIS, future edition 1 of IEC 60695-6-1, prepared by IEC TC 89, Fire hazard testing, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60695-6-1 on 2001-10-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement(dop)2002-07-01 latest date by which the national standards conflicting with the EN have to be withdrawn(dow)2004-10-01 Annexes designated “normative“ are part of the body of the standard. Annexes designated “informative“ are given for information only. In this standard, annex ZA is normative and annexes A, B and C are informative. Annex ZA has been added by CENELEC. _ Endorsement notice The text of the International Standard IEC 60695-6-1:2001 was approved by CENELEC as a European Standard without any modification. _ Page 2 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI CONTENTS Page INTRODUCTION 5 Clause 1Scope 6 2Normative references. 6 3Definitions and nomenclature . 7 4General aspects of smoke test methods. 9 4.1Fire scenarios and fire models 9 4.2Factors affecting smoke production11 4.2.1General11 4.2.2Modes of decomposition.11 4.2.3Ventilation and burning environment.11 4.2.4Time and temperature12 4.2.5Removal mechanisms for smoke particles12 5Principles of smoke measurement.12 5.1Bouguers law 12 5.2Extinction area.13 5.3Log10 units.14 5.4Light sources .14 5.5Specific extinction area 14 5.6Mass optical density.15 5.7Visibility.16 6Static and dynamic methods16 6.1Static methods.16 6.2Dynamic methods 16 7Test methods18 7.1Consideration of test methods18 7.2Selection of test specimen .18 8Presentation of data20 9Relevance of data to hazard assessment.20 Annex A (informative) Calculation of visibility22 Annex B (informative) Relationships between Ds and some other smoke parameters as measured in IEC 60695-6-30 and IEC 60695-6-31 .24 Annex C (informative) Relationships between percent transmission, as measured in a “three metre cube“ enclosure, and extinction area27 Annex ZA (normative) Normative references to international publications with their corresponding European Publications30 Bibliography 29 Page 3 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Page Figure 1 Different phases in the development of a fire within a compartment.10 Figure 2 Attenuation of light by smoke 13 Figure 3 Extinction area13 Figure 4 Dynamic smoke measurement 17 Figure 5 Evaluation and consideration of smoke test methods.19 Figure A.1 Visibility () versus extinction coefficient (k).22 Figure B.1 Smoke parameters related to Ds, as measured in IEC 60695-6-30 and IEC 60695-6-31.26 Figure C.1 Extinction area (amount of smoke) related to percent transmission as measured in the “three metre cube“.28 Table 1 General classification of fires (ISO/TR 9122-1).10 Table B.1 Conversion from Ds to some other smoke parameters as measured in IEC 60695-6-30 and IEC 60695-6-31 .25 Table C.1 Conversions from percent transmission, as measured in the “three metre cube“ to amount of smoke (extinction area) .27 Page 4 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI INTRODUCTION The risk of fire needs to be considered in any electrical circuit, and the objective of component, circuit and equipment design, as well as the choice of material, is to reduce the likelihood of fire, even in the event of foreseeable abnormal use, malfunction or failure. Electrotechnical products, primarily victims of a fire, may nevertheless contribute to the fire hazard due to the release of smoke, which may cause loss of vision and/or disorientation which could impede escape from the building or fire fighting. Smoke particles reduce the visibility due to light absorption and scattering. Consequently, people may experience difficulties in finding exit signs, doors and windows. Visibility is often determined as the distance at which an object is no longer visible. It depends on many factors, but close relationships have been established between visibility and the measurements of the extinction coefficient of smoke see annex A. The production of smoke and its optical properties may be measured simultaneously with other fire properties, such as heat release and flame spread. This part of IEC 60695 serves as a guidance document and focuses on obscuration of light by smoke. Page 5 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI FIRE HAZARD TESTING Part 6-1: Smoke obscuration General guidance 1 Scope This part of IEC 60695 gives guidance on: a) optical measurement of smoke obscuration; b) general aspects of optical smoke test methods; c)consideration of test methods; d) expression of smoke test data; e) relevance of optical smoke data to hazard assessment. One of the responsibilities of a technical committee is, wherever applicable, to make use of basic safety publications in the preparation of its publications. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this part of IEC 60695. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this part of IEC 60695 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of IEC and ISO maintain registers of currently valid International Standards. IEC 60695-1-1:1999, Fire hazard testing Part 1-1: Guidance for assessing the fire hazard of electrotechnical products General guidelines IEC 60695-6-2:2001, Fire hazard testing Part 6-2: Smoke obscuration Summary and relevance of test methods IEC 60695-6-30:1996, Fire hazard testing Part 6: Guidance and test methods on the assessment of obscuration hazard of vision caused by smoke opacity from electrotechnical products involved in fires Section 30: Small scale static method Determination of smoke opacity Description of the apparatus IEC 60695-6-31:1999, Fire hazard testing Part 6-31: Smoke obscuration Small scale static test Materials IEC Guide 104:1997, The preparation of safety publications and the use of basic safety publications and group safety publications ISO/TR 9122-1:1989, Toxicity testing of fire effluents Part 1: General ISO 5659-2:1994, Plastics Smoke generation Part 2: Determination of optical density by a single-chamber test ISO/IEC 13943:2000, Fire safety Vocabulary Page 6 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 3 Definitions and nomenclature For the purpose of this part of IEC 60695, the definitions taken from ISO/IEC 13943, together with the following definitions, apply. 3.1 extinction coefficient of smoke natural logarithm of the opacity of smoke divided by the path length of the light used to measure the smoke opacity 3.2 extinction area of smoke product of the extinction coefficient and the volume occupied by the smoke NOTE It is a measure of the amount of smoke. 3.3 specific optical density of smoke optical density multiplied by a geometric factor ISO/IEC 13943, definition 154, modified NOTE The use of the term specific does not, in this case, denote the 'per unit mass but rather denotes a quantity associated with a particular test apparatus and exposed surface area of the test specimen. The geometric factor is V /AL, where V is the volume of the test chamber, A is the exposed surface area of the test specimen and L is the light path length. 3.4 specific extinction area of smoke extinction area of smoke divided by the mass loss of the test specimen 3.5 mass optical density of smoke optical density multiplied by a factor, V/m L, where V is the volume of the test chamber, m is the mass loss of the test specimen and L is the light path length 3.6 fire model procedure or process intended to represent, predict or reproduce one or more phases of a fire, or the transition between phases ISO/IEC 13943, definition 51 3.7 flash-over transition to a state of total surface involvement in a fire of combustible materials within an enclosure ISO/IEC 13943, definition 77 Page 7 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI Nomenclature SymbolQuantityTypical units A exposed area of test specimenm2 D linear decadic absorption coefficient (commonly called optical density per metre) m1 D optical densitydimensionless mass Dmass optical densitym2 kg1 s Dspecific optical densitydimensionless ) ( m also max DD maximum specific optical densitydimensionless I intensity of incident lightW T/I ratio of incident light to transmitted lightdimensionless k linear Napierian absorption coefficient (commonly called extinction coefficient) m1 L light path length through smokem m mass loss of test specimenkg m ?mass loss ratekg s1 Ssmoke extinction area (also total smoke)m2 S ? smoke production rate (rate of change of extinction area)m2 s1 ttimes t sampling time intervals T intensity of transmitted lightW V volume of chamberm3 V ? volume flow rate of smokem3 s1 f specific extinction aream2 kg1 a constant of proportionality between visibility and extinction coefficient dimensionless visibilitym NOTE 1 The quantities based on log10, i.e. D, D, Dmax, Dmass and Ds, have similar symbols but they are different quantities and have different units. NOTE 2 The use of the term “specific“ in the case of specific optical density, Ds, does not denote “per unit mass“. Page 8 EN 6069561:2001 © BSI 22 November 2001 Licensed Copy: sheffieldun sheffieldun, na, Thu Nov 09 01:45:27 GMT+00:00 2006, Uncontrolled Copy, (c) BSI 4 General aspects of smoke test methods 4.1 Fire scenarios and fire models During recent years, major advances have been made in the analysis of fire effluents. It