BRITISH STANDARD SPECIFICATIONFIRETESTS O N BUILDING MATERIALS AND STRUCTURES.. B.S. 476 :Part 1 :1953 . BRITISH STANDARDS INSTXTUTION IN CORPORATBD BY ROYAL CHARTER BRITISH STANDARDS HOUSE, 2 PARK S . LONDON, W.1 T, COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services B S I BS*47b: PART*L 53 m 1624669 t 02933bb 9 m1 B.S. 476 : Part 1 : 1953 THIS BUTEH STANDARD, having been approved by the Building Divisional Council, was published under the authority of the General Council on 20th July, 1953. First published December, 1932. First revision July, 1953. The Institution desires to call attention to the fact. that this . British Standard does not purport to include all the necessary provisions of a contract. In order to keep abreast of progress in the industries concerned, British Standardsaresubject to periodicalreview. Suggestions for improvementswill be recorded and in due course brought to the notice of the committees charged with the revision of the standards to which they refer. A complete list of British Standards, numbering over 4000, indexed andcross-indexed for reference,togetherwithan abstract of each standard, will be found in the Institution's. Yearbook. British Srartdards are revised, when necessary, by the issue either o anlcndment slips or o revised editions. It is imporf f tarrt that users o British Stattdar& should ascertain thnt f /ht.y ore it1 possession of the lot¿st amendtttents or editions. -_ 4 / I , 2 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services R.R. London County Council London Fire Brigade Ministry of Works National Federation of Budding Trades Employers .S.-Building Research Station D. Reinforccd Concrete Association Royal Tnstitute of British Architects Q ' \ c.-Forest Products Research Laboratory Federation of British Industries Fire 01Sices Committee Fire Offices Committee. Fire Protection Association Tnstitution of Fire Engineers Institution of Municipal Engineers Joint Fire Research Organization of the Department ofScientific and Industrial Research and Fire Offices Committee .S.The Committee responsible for the preparation of +i this ßritish Standard consists of representatives from.I.1. COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . the following Government departments and scientific and industrial organizations : British Constructional Steelwork Association British Electricai and Allied Industries Research Association British Fire Services' Association Building Industries National Council I3. " " " i " . 7 : . " . " ing th&urface sfiad of f l a m h r 1íningMeriaIs/ . . .. the use of the term in this standard is restricted to theperformance of complete elements of building structure . Fire-resistance o f structures. " . without individual regard to the performance of the materials of which they are composed. . " 1 . . '== . Materials which perform weil in the cornbustibilit).. i . 4 ~ COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services ."_ . . e .". 7 F ~ " " ..e .* or surface spread of flame tests may not necessarily do so when I built into an element of structure and subjected to the fire-resistance test. -.. . Cornbustìbilìt y. . " " . .-<. Although the term ' fire-resistance ' has often been ~scd indiscrirninately in the past to denote the resistance of materiais to ignition or spread of flame. Where a firebccurs in a compartment of a building. . 476 : Part 1 :1953 1 BRITISH STANDARD SPECIFICATION FOR FIRE TESTS ON BUILDING MATERIALS AND STRUCTURES . FOREWORD The purpose of this British Standard is to spe6iy a series of testsfor determinKing those properties of building materials and structures which are relevant when considering the fìre protection o buildings in which they f be may are to used. and by which such materials and structures be accepted or rejected..S. *-- i . .B. The fireresistance test of Section Three grades elements of building structures in accordance with the time for which they are capable of fulfilling these fuxtions while subjected to heating conditions representative of an actual fue in a compartment. the structure of the compartment should be required to contain the fire by continuing to perform those of its normal functions which contribute to the integrity and insulation of the compartment.__ __ "= --. " : .. la). has been deleted as.__" . The water test . 1547. ". ' Flameproofindustrialclothing * would be more satisfactory. as it is felt in some quarters that the former term more appropriate. this proportion being chosen as acceptablysmallfor safety reasons. The calculation of the performanceof the material is s u d that credit is given to materials of uniform standard.B. for which purpose it was considered that a test similar to that given in B.. while the 10-minute limit of Class 3 is more rigorous. the classification of . This test was sometimes found 'to give anomalous results. :'r "~ -- COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .for is the purposes of the tests. For load-bcaring structures. The values of the limits are derived from all available testing experience to date.S.*r** c - ' "- . 476. balance between J $4-minute and final or 10-minute values. " " -- 3fifih +. as it has long been felt that the reasons advanced for imposing one and a half times the design load were not necessarily valid in every instance. andshow an improved. The kethodof classifìcatlon of materials in the surface spreadflame of test has been amended. loading has beea reduced to the design the load. since variabilityis peiîalized by requiring r? correspondingly higher standard of general performance if m y particular classificationis to bc attained.. 1. While mean spread gives a measureof the generalstandard of performance 1 of a material. " s i - * Lb- - \ .. Alterations to the standard. it does not take account the variability which is known to of occur in the performance of different samples of most materials.S. the former having been made considerably more rigorous. In the last edition of B. It is also in keeping with American test practice. . It was mostly applied to fabrics and decorative materials.it could not be applied to all types of structura nor S . The present methôd is intended to do this by classifying matefiais in such a way that not more than 1 per cent of a material is likely to have a performance below the standard of the class in which the material is placed. although the tolerance on the curve has had to be increased for conducting specimens in tests of longer than ?&hour duration. The final limit of Class 2 is the equivalent of that used hitherto. In the present revision. a material rested on the mean spread of a certain number of specimens. In the fire-resistancetest it has been considered desirable to standirdize all the method of control of the furnace temperature for types of specimen to that of the standard time-temperature curve pig. of the standard some major alterations have been made.S. as follows:The non-inflammability test has been deleted. 476 :Part 1 : 1953 Consideration isbeinggiven to the substitution of the term a fìrc endurance ' for the term a fìre resistance ' as used in this British Standard. The impact test has been-deleted as.S. . it was not a satisfactory measure of the weakening effect of a fire. . :.<* - I.the f ~ l l size apparatus required for the surface spread of flame lest specified in this British Standard.. . . It is emphasized that this is not intended to bequoted in place of the standard test. II this thicknes 7 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . It was found to destroy much useful evidence of the behaviour of a structure and was rarely R deciding issue. " SECTION ONE: COMBUSTIBILITY TEST OF~MATERIALS . ._ - ~ _. from obtained the specified test..B. in generaI. 476 : Part 1 : 1953 could it be applied during the heatingperiod as is likely in practice. . . . SPECIFICATION . and is purely for-thelpurpose of obtaining in an economical manner an approximation of the values that will be . SCOPE . it has not yet been found possible to devise a satisfactory.. An appendix has been added to the standard giving details'of a'tesi which may be used by those wishing to ascertain the probable spread of flame values of a material without the necessity for constructing . alternative.. . This British Standard specifies tests 'for detcimining those pro$erties of building materials and structures relevant when considering the protection against fire of the buildings in which-they are to be used. - . 476 : Part 1 : 1953 Y I INITION OP S L f 7 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .B.S. I alumel thermocouple and shall issue fr more than y4 in.35 The room in which th contact with t 8 of the time of COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . . after whic eu to a wooden'. " " ".B S I BS*476: PART*L 5 3 E 1b24bbS 0293172 4 m I B. raised to the following val f 3 per cent : . (6. 476 : Part 1 : 1953 ingredients of which shall be conditioned in Clause 8.S. . 476 : Part 1 : 1953 ? . COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .BSI BS*47b: PART*I.S. 5 3 E Lb24bb9 0293373 b E B. S. Load-bearing and non-load-bearing walls and . .05m. or 10 ft. . (r. Ali test elements shall be fuli size wherever possible.. it shall be tested by analogy with thc most 'similar. and N 1. x 3-05 m.. floors.41 and 1 -43 be o f 4 t " " u y grade in t h p f an r x the ratio? to soda is bet . : .O5 m. the testing authority shall 'test a representative portion of thc full size element having dimensions not Icss than 10 ft.O5 m ) or being 10 ft.partitions . .. X 10 ft. as-defined by existing relevant codes nd 10 z I COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services ~ .-~ ~ < - ~~ - ~ -- . beams.) in Icngth.B S I BSM47b: PART*1 53 1b24bb9 0293374 A I B. Glazing Doors and shutters Columns Beams Floors Roofs ' .) for walls. f b. X 10 ft. Constrrrction and conditionhg o tesr clement... y. a permanent 5 . Size of test element of structure.) &r coiumns. L . as applicable. category. etc. roofs. d TEST PROCEDURE 10. therefore where an clement faIls into nonti of. (3 -05 m. Where the full dimensions exceed 10 ft. The silicate osition shall confo he foIlówing pn *s o :- Water aqueous s y 3-2 SiO. . (3 . 3 *4 SiOo and Ich h specific avity betwee ~ /g/ . The materials and standard of workmanship of the test element shall be representative of those applying in good practice..05m. etc. . I 3 " This list is not exhaustive. length (3. 476 :Part 1 : 1953 y ?' O F SODXUM S r I ' T I O N 8. (3.. X 3 .: these categories. 1. by prior agreement betweea the sponsor of the test and the testing authority. " - . For thepurpose of special applications. d. (1700°F.l be deemed to be the average of the readings of not less than 6 thermocouples disposed within the furnace so that they may fairly represent its average temperature. and shall be re-applied 48 hours 'after the end of the heating period. to separate spaces shall be heated over the whole of one face only. unless failure has already occurred.) 704°C. Method o test.: 1953 -standards. The test element shall be conditioned to reproduce the state in which the element is likely to be when inservice in a building.) 843OC. and this performance shall be regarded as representative of thestructure. C. The hot junction of each thermocouple shall be placed 3 in. is likely to give the least resistance. (76. Structures such as walls containing flues. Freestanding columns shall be heated from all radial directions over their whole height. The applied loading shall be kept constant during the heating period. . The temperature of the furnace shall be controlled to follow.?" " COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . and shall not be allowed to touch the surface. The test element shall be heated in a furnace thef temperature of which sha1. Those which may be required to resist fire in either direction shall normally be tested in the direction which. (1850°F. and the report of the testing authority shall be annotated to this effect.2 mm. which are normally heated in service. to give the better performance. (1 300°F. in the opinion of the testing authority. (2050°F. Non-load-bearing test elements shall not be loaded during test. A load-bearing testelement shall be subjected to a loading which produces the same maxhum stress as would be produced in the full-' size element when the latter is subjected to the maximum loading that itis designed to support. (1 550°F.) 1010°C. (1000°F. Restrnint and foading. at 5 minutes at 10 See Fig. a separating structure normally required to resist fire from either direction may.S. 476 :Part 1 .B S I BSr47b: PART*L 5 3 W L b 2 4 b b 9 0293375 T m I B.) 1121OC. shall be heated similarly during test. Structures whose function is. Points on this curve which define its character are:538°C. be tested from the side likely.) 1204°C. v: \ -~ .) from the nearest point of the specimen.) 927OC. Therestraint applied to t h e test element shall be similar to that spplied to the element in service. in the opinion of the testing authority. as closely as possible. should any distortion of the latter occur during the test. the standard time-temperature curve shown in Fig. I (b) at 30 minutes at 1 hour at 2 hours at 4 hours at 6 hours 11. Those which may be required to resist fire in one direction only shall be tested accordingly and the report of the testing authority shall be annotated to this effect. ( 2 0 F ) 20°. one approximatcly at the centre of thc. . provided that no point is closer than 12 in. . (iii) The area under the test furnace temperature-time curve does not differ from the area under the standard curve by more than the appropriate percentage of thelatterarea. - . In addition. during rest. f. The test element shall normally be heated .' 15 . .at any fimc.)to the edge.) during the first 10 minutes of test.B S I BSx47b: PART*KL 5 3 m l b 2 4 b 6 90 2 9 3 3 7 6 3 E I .5cm. 476 : Part 1 : 1953 The accuracy of the furnace control shall be such that: (i) The.' be measurcd at the point that appears to be hottest. ~. Observariorrs ~.~ COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . . . (ii) The furnace temperature does not vary from that shown by the standard curve by more than f 167 Centigrade degrees (+ 300 Fahrenheit degrees) at any timeafter the first 10 minutes of test..furnacetemperaturedoesnot excekd 871OC. the'tempcratGrc ma.in 'the .< " Elements Elements subject to re. ' ' I 1 0 1 0 5 . Dwution of rest. during the test. % 4i-1 1-2 More than 2 1 per cent ~ per cent . the surface temperature of the unexposed face shall be measured at not less than five points. 15. The average temperature of the unexposed surface shall bedeemed to be the averige of the temperatures mcasured at these points. .54 cm..subject toreDuration of t e t quirements of quirements of Clause 11 CI. c ri. .shutters' and -glazing. . . . other than those on such items as doors.~ 15 -15 . . Clause 11 b. (2. against which combustible material would not be placed in service.) diameter copper disk which shall be secured to the surface of the element at the required position. 1 i -. (30.:and one approximately at the centre of each quarter section: Any points of measurement additional to these five shall be disposed as uniformly as possible over the unexposed face of the elkment. . . . shown inthe following Tabk 1. In tests on elements with an unheated : surface. . . MAXIMUM TOLERANCE ON AREA UNDER STANDARD FURNACE TEMPERATURE-TIME CURVE . . hr. This temperature shall not be used in-determining the average tempzraturc but may be used in determining the maximum temperature..'face. These surface temperatures shall be measured by means of thermocouples. b only . each attached to the face of a 1 in. .S. 12 e. B. TABLE 1. (1600°F. . 2 3 4 5 f Fig.S.B S I BS*47b: P A R T x l 5 3 I3 b 2 4 b b 9 2 9 3 3 7 7 0 3 I 1 B. COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . 476 : Part 1 : 1953 1300 2 2c 1200 10 10 180( """- "_ I " " " 1000 160( 900 ' " " " " " " " " " " " " " " " " i " < doo 500 60[ " " " " " i " " " . 1 (a). " " _-. 400 . Time-temperature curve 13 r."""- ""_" _" 6 - "_ 200 200 " " " " " " " " " " O0 O L.. 30 40 50 60 TIME.B.S. 476 : Part 1 : 1953 1 0 20 .MINUTES 14 COPYRIGHT British Standards Institute on ERC Specs and Standards c Licensed by Information Handling Services . . . Where a test is terminated by agreement. . . shutters and giazing. > 11. if failure has not already occurred under the relevant test requirements. Pussnge offlume. T h e testresult 'shall be stated in 'terms " " '> DEPINTIONS O F FIRE-RESISTANCE - . it is required that cracks. of the time. prescribed manner until failure has. For all elements of structure. For all elcrncn. Grading periodr ?4hour 1 hour 2 hours 3 hours 1 hours 6 hours . .Fahrenheit degrees) . . in hours and minutesBfrom the commencement of heating. but does not exceed. flame can pass shall not develop. . 15 . TFST RESULTS . u. . .occurred under ali the relevant test. The fire-resistanceof an element of structure shall be the grading . nor reach a value higher. the sponsor o the test and the testing authority. 12. this shall be stated in the report. the heatingperiod may be concluded f after any one of the periods stated in Clause 12. .This requirement may be waived for elements such as doors. 221°C.$heheating period may be concluded at any time after failure has occurred under at 1east:one of the relevant test requirements. fissures or other orifices throuBh which. f I. . b. Collupse.ts of strdcture whose-function is to separate spaces and hence to resist the passage of fire from one space to ahother. against whichit is not intended that combustible material should be placed in service. . for. . provided that the statement of test result in the report of the testing authority' is qualified by the statement that the insulation requirement was waived.. For all elements of structure as in b abovk.. the test period for which the element fulfils all the relevant test requirements. Alternatively. .' COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . than. which the element of structure complies with those of the following three requirements which are relevant to it. c. . by prior agreement between. it is required that th? average temperature of the unexposed surface shall not increase by more than 139 Centigrade degrees (250 . . except that by agreement hetween the sponsor of the test and thc testing authority . requirements af Clause 11. InsuZrrion.. 476 :. . . - B.above' the initial temperature. Part 1 : 19S3 .S. period shown below which is most nearly equal to. 40F) whichever is the lesscr value. and that t.. ( 3 " .he temperature-of the inexposed face shall not increase at any point by more than 180 Centigrade degrees (325 Fahrenheit degrees). it is required that theeleníent shall not collapse. . 476 : Part 1 : 1953 This principle shall also an agreed period o heating.after .BSI BSs47b: P A R T r l 53 m 1 3b24bb9 293380 0 3 m B. -_ 13. for a particular application. if relevant. APPENDIX APPARATUS F of surfaces as d fficient to warra ircumstanccs whc 16 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . PARTICULAR APPLICATION . but not exceedïig. ? ' e b followed where a .i -. . a pteckpting authority 'waives either or both of the requirements of Clause 11 (b) and (c).a .test is terminated. Where. the element may then be regarded for theprposes of the particulap application only. the test period for which"ihe remaining test requirement or requirements are fulfilled. or requires their fulfilment only for some pre-determined period. as providing a fireresistan& equal to that grading period most nearIy equal to.S. ' High dumina cement. ! S ' ¡.' 17 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .B.S... 476 :Part 1 : 1953 position by a suitable . !S 915. COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . (30- fa& of which asbestos fluctuations in the te 6 . either minutes whichever is the longer.S. 476 : Part I : 1953 i ment.that the 1 ft. centre-line of the specimen.BSI B S * 4 7 6 : PART*:L 5 3 M 3 b 2 4 b b 9 2 9 3 3 8 2 0 7 m 3. (2 . e whole sample. Those sur not more than e 1 cm. . COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . If .. minute or exceeds 8% in.) during thè . . I the specimen should ery low flame spread.S. 476 :Part 1 : 1953 . _.B S I BS*47b: PARTEL 5 3 m Lb24bb9 293383 0 9 m B. m 1 c COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . Fire\. 21 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .spread of at the Joint . square radiation panel . 476 :Part 1 t. O in. 1953 / . blower ' 5 h COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .B S I BS*476: PART*L 5 3 M L624669 0293LBb 4 M j B. t.S. BSI BS*47b: P A R T * & 53 I3624669 0293387 b m I L B. 476 : Part 1 : 1953 t rig. .S. Arrangement of ‘ CO r-disk & therruocouple :8 t . COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .. 5. -.. paint ingredients adcolours for paints (SL9) Personal sdety equipnlent (SI. varnishes. excluding laboratory apparatus (SL39) Heating. . (SL 4) Cinematography and photogr-aphy (SL 1) .l i ' L . Furniture. .. glues. (SL 17) iron and steel (SL 24) Laboratory apparatus (SL 23) Leather. paper and board (SL 22) Road enginccring (SL 32) Shipbuilding (SL40) Textilcs and clothing (SL 33) Welding (SL 7) 6 .3 ) 0 Pctroleum industry (SL 35) Printing.42). . Non-ferrous metals (SL 19) Nuclear energy (SL 36) Packaging and containers (SL15) Paints. . N. soap..BSI Bs*K47b: PART*3 5 3 IL b 2 4 b b 9 2 9 3 3 8 8 0 8 m . Gratis . BRITISH STANDdDS The following are available on application: -r. including Universal Decimal Classification (SL 35) . Hospital cquipment (SL 18) Illumination and lighting fittings (SL 14) Industrial instruments. Coal. . '3 . . . BRITISH - - c COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . . rubber (SL 12) Local authority purchasing officers' guide (St28) Machine tools (SL 20) Mechanical engineering (SL 6) Namcnclature. . p. fats. London. / : 3 . Drawing practice (SL 37) Electrical Engineering (SL 26) Farming. Applications should be addressed to: STANDARDS INSTITUTION Sales Branch Telephone: 01-278 2161 Newton House.1 .beddingandfurnishings (SL 11) : Gardening.. 101/113 Pentonville Rd. symbols and abbreviations (SL 29) . horticulture and landscapc work (SL 41) . *. oils.$ ?. dairying and allied interests (SL 31) . Gas and solid fuel and refractories (SL 2) Glassware. and stationery. etc. ventilating and air conditioning (SL. coke and colliery requisites (SL 13) C'odes of Practice (SL 8) Consumer goods (SL 3) Documentation. Acoustics (SL 10) Aerospace materials and components (SL 25) Automobile (SL 34) i British Standard Handbooks (SL 27) Building (SL 16) Chemical engineering (SL 5 ) Chemicals. etc. SECTIONAL LISTS. plastics. Y EARBOO K 'Including subject index and numerical list of British Standards 15s. Membership of the Institution is open to British subjects.-- . companies. . The Institution is a non-profit-making concern. L COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services .. standardizationand . Before embarking on any project it must be satisfied that there is a strong body of opinion in favour of proceeding and that there is a recopiied need to be met. and low1 and public authorities. to eliminate the waste of time and material involved in the production of an unnecessary variety of patterns and sizes of artides for one and the same purpose.. .1929. . Thc principal objects of the Institution as set out in the charter are to co-ordinate the efforts of producers and users for the improvement. It is financed by subscriptions from' firms. sinlplification of engineering and industrial materials. to simplify production and distribution. to set up standards of quality and dimensions. technical and trade associations. by a Government grant and by the sale of its publications. trade aseociations. The demands on the services of the Institution are steadily increasing and can only be met if continuing and increased financial support is provided. interested in its work. and to promote the general adoption of British Standards. professional institutions and other bodies . In carrying out its work the Institutiön endeavours to ensureadequate representation of all viewpoints.I BRITISH STANDARDS INSTITUTION The British Standards Institution was founded in 1901 acd incorporated by Royal Charter in . Part 4. Delete thethirdparagraph the combustibility test.S.'i II j E Amendment Slip No. 476. This Amendment deletes that material.. ~. 1." " . now published. - -~_ .' to 'the pilot flame. B. published 26 January. 476 : Part ~~ NOTE. 'Non-combustibility 1. . 1 test for materials'.S. 'Fire tests on building materials and structures'. AMD 409 I .'. "" ." ~ " "~ . supersedes some of the material h this standard. 1970 1 : 1953 Fire ieests on building materials and structures. COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . to B. of this clause. Alterationstothestandard. from% j! I I . ~ Amendment Slip No.9 prnd 3. uses. 476. Delete this paragraph. Alleralions to the srondard. * .. supersedes some of the material in this standard- I i Deletion Foreword (samended by Amendment No.B S I BS*q7b: P A R T S 1 5 3 E l b 2 4 6 6 7 027317l 8 E ~. B. 'Surface spread of flame for tests materials'. i 1 L - .figures. 476 : Part 1 : 1953 Fire tests on building materials and structures . section two. Delete th. NOTE. L 1 COPYRIGHT British Standards Institute on ERC Specs and Standards Licensed by Information Handling Services . . Figs. Qnapes 5. published 18 Febmary.S.< i This Amendment deletu that material. Delete c. -la Appendix.-l!Hl to B.S. now published.1) a Swface spread of firne. . . 2. 6. 7 a d 8. 1i I t= h 1 .Part 7. Surface spread of Barne test for materiah Delete the section heading. . I ! . . Delete the fourth and seventh paragraphs. AppolrahtP for wellminary surface spread of liame test Delete this Appendix.3. 'Fire tests on building materials and s1ructum'.