1、BRITISH STANDARDBS 476-12:1991Fire tests on building materials and structures Part 12: Method of test for ignitability of products by direct flame impingement1991Incorporating Corrigendum No. 1ICS 13.220.50BS 476-12:1991This British Standard, having been prepared under the direction of the Fire Stan
2、dards Policy Committee, was published under the authority of the Standards Board and comes into effect on 30 August 1991 BSI 01-1999The following BSI references relate to the work on this standard: Committee reference FSM/1 Draft for comment 90/36346 DCISBN 0 580 19833 2Committees responsible for th
3、is British StandardThe preparation of this British Standard was entrusted by the Fire Standards Policy Committee (FSM/-) to Technical Committee FSM/1, upon which the following bodies were represented:Association of British Roofing Felt Department of Transport (Marine Directorate)Manufacturers Engine
4、ering Equipment and Materials UsersAssociation of Building Component AssociationManufacturers Eurisol (UK) Mineral Wool AssociationAssociation of Structural Fire Protection Fibre Building Board Organisation (FIDOR)Contractors and Manufacturers Fibre Cement Manufacturers AssociationBritish Cement Ass
5、ociation LimitedBritish Fire Services Association Flat Glass Manufacturers AssociationBritish Floor Covering Manufacturers Flat Roofing Contractors Advisory BoardAssociation Gypsum Products Development AssociationBritish Plastics Federation Home OfficeBritish Railways Board Institution of Fire Engin
6、eersBritish Rigid Urethane Foam Manufacturers London Fire and Civil Defence AuthorityAssociation Loss Prevention CouncilBritish Wood Preserving and Damp-proofing Mastic Asphalt Council and EmployersAssociation FederationChemical Industries Association National Council of Building MaterialChief and A
7、ssistant Chief Fire Officers ProducersAssociation National GRP Construction FederationConcrete Society National House-building CouncilDepartment of Education and Science RAPRA Technology Ltd.Department of the Environment (Building Royal Institute of British ArchitectsResearch Establishment) Steel Co
8、nstruction InstituteDepartment of the Environment (Construction Timber Research and DevelopmentDirectorate) AssociationDepartment of the Environment (Property United Kingdom Atomic Energy AuthorityServices Agency) Warrrington Fire Research CentreDepartment of the Environment for Northern Wood Wool S
9、lab Manufacturers AssociationIrelandThe following bodies were also represented in the drafting of the standard, through subcommittees and panels:Autoclaved Aerated Concrete Products Polyethylene Foam Insulation AssociationAssociation Queen Mary CollegeBritish Carpet Manufacturers Association Suspend
10、ed Ceilings AssociationLtd. Thermal Insulation Manufacturers andBritish Steel Industry Suppliers Association (TIMSA)GAMBICA (BEAMA Ltd.) Yarsley Technical Centre Ltd.Phenolic Foam Manufacturers AssociationAmendments issued since publicationAmd. No. Date CommentsBS 476-12:1991ISBN 978 0 580 85686 0Am
11、endments/corrigenda issued since publicationAmd. No. Date CommentsC1 March 2014 Information added to ForewordThis British Standard, having been prepared under the direction of the Fire Standards Committee, was published under the authority of the Standards Board and comes into effect on 30 August 19
12、91 The British Standards Institution 2014 Published by BSI Standards Limited 2014The following BSI references relate to the work on this standard: Committee reference FSM/1 Draft for comment 90/36346 DCBS 476-12:1991 BSI 01-1999 iContentsPageCommittees responsible Inside front coverForeword ii1 Scop
13、e 12 Definitions 13 Principle 14 Safety considerations 15 Apparatus 16 Conditioning and testing atmospheres 77 Ignition source application times 78 Specimens 79 Room ventilation 810 Procedure 811 Report 9Appendix A Result sheet 12Appendix B Use by specifiers 14Figure 1 Burner carriage 3Figure 2 Burn
14、er for ignition sources D and E 4Figure 3 Test frame with draught shields 5Figure 4 Restraining combs for thermoplastic and flexible materials 6Figure 5 Surface ignition 10Figure 6 Bottom edge ignition 11Table 1 Specimen size and flame application times 7Publication(s) referred to Inside back coveri
15、 The British Standards Institution 2014BS 476-12:1991ii BSI 01-1999ForewordThis Part of BS 476 has been prepared under the direction of the Fire Standards Policy Committee.Whilst this test has been designed to give information on the performance of a product in the early stages of a fire, it should
16、not be considered or used by itself for describing or appraising the fire hazard of a material, composite or assembly under actual fire conditions. Neither should it be used as the sole source on which a valid assessment of hazard pertaining to ignitability can be based. A series of second generatio
17、n “reaction to fire” tests are under preparation in ISO/TC 92, Fire tests on building materials, components and structures. The United Kingdom is participating in this work, and it is intended to offer this test for consideration.This Part of BS 476 has been produced in response to the perceived nee
18、d for tests which will assess the response of building materials and products to any of a range of primary sources. The test regime does not involve the imposition on the test specimen of any irradiation other than that from the ignition source. Although the sources specified in the test have been c
19、hosen to represent the heating characteristics of a number of statistically important real-life ignition sources, such as a match flame or electrical sources, they are all flame sources, some diffusion, some pre-mixed. These flame sources are matched, as far as practicable, in terms of intensity and
20、 area of heating and together represent a range of both characteristics. In the long term, specifiers may lay down requirements related to particular levels rather than requiring all tests to be carried out. This may require the provision of rules for re-testing if the results of testing differ for
21、each specimen. An example of such rules is given in appendix B.The method has been subjected to a wide ranging interlaboratory trial involving six laboratories and 26 different materials.Attention is drawn to the Health and Safety at Work etc. Act 1974, and the need to ensure that the method of test
22、 specified in this standard is carried out under suitable environmental conditions to provide adequate protection to personnel against the risk of fire and inhalation of smoke and/or toxic products of combustion.Appendix A gives a recommended form of result sheet.A British Standard does not purport
23、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.Summary of pagesThis document comprises a front cover, an inside front cover, p
24、ages i and ii, pages1to 14, an inside back cover and a back cover.This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS 476-12:1991ii BSI 01-1999ForewordThis Part of BS 476 has been pre
25、pared under the direction of the Fire Standards Policy Committee.Whilst this test has been designed to give information on the performance of a product in the early stages of a fire, it should not be considered or used by itself for describing or appraising the fire hazard of a material, composite o
26、r assembly under actual fire conditions. Neither should it be used as the sole source on which a valid assessment of hazard pertaining to ignitability can be based. A series of second generation “reaction to fire” tests are under preparation in ISO/TC 92, Fire tests on building materials, components
27、 and structures. The United Kingdom is participating in this work, and it is intended to offer this test for consideration.This Part of BS 476 has been produced in response to the perceived need for tests which will assess the response of building materials and products to any of a range of primary
28、sources. The test regime does not involve the imposition on the test specimen of any irradiation other than that from the ignition source. Although the sources specified in the test have been chosen to represent the heating characteristics of a number of statistically important real-life ignition so
29、urces, such as a match flame or electrical sources, they are all flame sources, some diffusion, some pre-mixed. These flame sources are matched, as far as practicable, in terms of intensity and area of heating and together represent a range of both characteristics. In the long term, specifiers may l
30、ay down requirements related to particular levels rather than requiring all tests to be carried out. This may require the provision of rules for re-testing if the results of testing differ for each specimen. An example of such rules is given in appendix B.The method has been subjected to a wide rang
31、ing interlaboratory trial involving six laboratories and 26 different materials.Attention is drawn to the Health and Safety at Work etc. Act 1974, and the need to ensure that the method of test specified in this standard is carried out under suitable environmental conditions to provide adequate prot
32、ection to personnel against the risk of fire and inhalation of smoke and/or toxic products of combustion.Appendix A gives a recommended form of result sheet.A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their
33、 correct application.Compliance with a British Standard does not of itself confer immunity from legal obligations.Summary of pagesThis document comprises a front cover, an inside front cover, pages i and ii, pages1to 14, an inside back cover and a back cover.This standard has been updated (see copyr
34、ight date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS 476-12:1991 The British Standards Institution 2014This part of BS 476 is published by BSI Standards Limited, under licence from The British Standards Institution.This stand
35、ard has been superseded by the current BS EN ISO 11925-2, but it has been retained based on legitimate need for the standards within non-EU markets.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance wi
36、th a British Standard cannot confer immunity from legal obligations.BS 476-12:1991 BSI 01-1999 11 ScopeThis Part of BS 476 describes a method of test for the determination of the ignitability of materials, composites and assemblies subjected to direct impingement of flames of different size and inte
37、nsity but without impressed irradiance.NOTE The titles of the publications referred to in this standard are listed on the inside back cover.2 DefinitionsFor the purposes of this Part of BS 476, the following definitions apply.2.1 sustained ignitionafter withdrawal of the ignition source, the presenc
38、e of a flame on the surface of the specimen that persists for at least 10 s2.2 transient ignitionafter withdrawal of the ignition source, the appearance of flashes, or flames, which are not sustained for a continuous 10 s2.3 progressive smoulderingan exothermic oxidation not accompanied by flaming w
39、hich is self-propagating, i.e. independent of the ignition source, and may be accompanied by incandescence2.4 flaming debrismatter flowing or separating from the specimen during the test procedure and falling below the initial lower edge of the specimen and continuing to flame as it falls2.5 afterfl
40、amepersistence of flaming of a specimen, under specified test conditions, after the ignition source has been removed2.6 afterglowpersistence of glowing of a specimen, under specified test conditions, after cessation of flaming or, if no flaming occurs, after removal of the ignition source2.7 flame a
41、pplication timethe time (in seconds) for which the burner is in its final testing position2.8 constant massthe state of a test specimen when two successive weighing operations, carried out at an interval of 24 h, do not differ by more than 0.1 % of the mass of the specimen or 0.1 g, whichever is the
42、 greater3 PrincipleVertically held specimens are exposed to specified flames of different sizes and intensities and their ignition behaviour is observed. The flame is applied to the surface and/or a bottom edge on different specimens.4 Safety considerationsThere are hazards with these tests and it i
43、s essential that adequate precautions are taken. Particular attention should be paid to: the handling of flammable gases; the evolution of potentially toxic gases; and the fact that extensive flaming of specimens may occur.Between tests, the atmosphere of the testing room (see 5.1) should be cleared
44、 of smoke and toxic gases by an extractor fan or other means of ventilation. The required atmosphere for testing should be restored.Adequate means of extinguishing the specimen should be provided, bearing in mind that some specimens may produce severe flaming during the test. A hand and/or fixed wat
45、er spray which can be directed over the burning area should be available with other means, such as fire extinguishers (see BS 5423) and fire blankets (see BS 6575).NOTE In some cases, smouldering may be difficult to extinguish completely and immersion in water may be necessary.5 Apparatus5.1 Testing
46、 room. A room equipped with an extractor fan or other means of ventilation and capable of providing a substantially drought-free environment at between 10 C and 30 C and a relative humidity of 50 20 %.NOTE 1 It is recommended that the testing room be divided into two parts, the inner part for carryi
47、ng out the tests and easily viewed from the outer part in which control equipment would be situated.NOTE 2 It has been found that a partially darkened room assists with the perception of small surface flames.For ignition sources D, E, F and G, either a testing room with a minimum volume of 20 m3is r
48、equired, or alternatively, a smaller enclosure with a through flow of air. If the latter is used it shall be equipped with inlet and extraction systems with air flow rates between 0.02 m/s and 0.2 m/s in the locality of the test specimen.BS 476-12:19911 The British Standards Institution 2014BS 476-1
49、2:19912 BSI 01-1999These limits provide adequate oxygen without disturbing the burning behaviour.NOTE 3 Testing with ignition sources A, B and C may be carried out in either of these environments, or in a suitably ventilated fume cupboard.5.2 Propane supply and regulation. A supply of commercial propane complying with BS 4250-1 connected to the ignition sources by the following.a) A cylinder regulator complying with BS 3016 with an outlet pressure of 1 bar1)absolute.b) An appropriate length of 5 mm internal diameter high pressure hose to BS 3212.c)
