1、Designation: D3806 98 (Reapproved 2011)Standard Test Method ofSmall-Scale Evaluation of Fire-Retardant Paints (2-FootTunnel Method)1This standard is issued under the fixed designation D3806; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method determines the protection a coatingaffords its substrate, and the comparative bur
3、ning characteris-tics of coatings by evaluating the flame spread over the surfacewhen ignited under controlled conditions in a small tunnel.This establishes a basis for comparing surface-burning charac-teristics of different coatings without specific consideration ofall the end-use parameters that m
4、ight affect surface-burningcharacteristics under actual fire conditions.1.2 In addition to the experimental flamespread rate, theweight of panel consumed, time of afterflaming and afterglow,char dimensions and index, and height of intumescence may bemeasured in this test. However, a relationship sho
5、uld not bepresumed among these measurements.1.3 This standard should be used to measure and describethe properties of materials, products, or assemblies in responseto heat and flame under controlled laboratory conditions, andshould not be used to describe or appraise the fire hazard or firerisk of m
6、aterials, products, or assemblies under actual fireconditions. However, results of this test may be used aselements of a fire risk assessment which takes into account allof the factors which are pertinent to an assessment of the firehazard of a particular end use.1.4 The values stated in SI units ar
7、e to be regarded as thestandard. The values given in parentheses are for informationonly.1.5 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practice
8、s and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C220 Specification for Flat Asbestos-Cement SheetsD344 Test Method for Relative Hiding Power of Paints bythe Visual Evaluation of BrushoutsD1475 Test Method For Density of Liquid Coat
9、ings, Inks,and Related ProductsD2196 Test Methods for Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield type) Vis-cometerE84 Test Method for Surface Burning Characteristics ofBuilding Materials2.2 Federal Standard:Fed. Spec. TT-V-119 Varnish, Spar, Phenolic Resin33. Signifi
10、cance and Use3.1 A number of laboratory procedures are used to evaluatethe effectiveness of fire-retardant and fire-resistant treatmentsand coatings. In general, these methods measure the threestages of fire development: (1) ignition; (2) flame spread (rateof growth of the fire); and (3) conflagrati
11、on extent. While allthree are of extreme importance, flame spread has beenrecognized as the main factor associated with testing fire-retardant coatings.3.2 Flame spread ratings based upon Test Method E84 haveacquired common acceptance by regulatory agencies, but suchlarge-scale tests are seldom prac
12、tical during the developmentor modification of a fire-retardant coating.3.3 This test method provides the relative flame spread ofexperimental coatings using small test specimens. By calibrat-ing the 2-foot tunnel with Test Method E84-rated fire-retardantpaint, results obtained by this test method s
13、hould be indicativeof those obtained with a large specimen in theTest Method E84tunnel.1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings, Materials, andApplications and is the direct responsibility ofSubcommittee D01.21 on Chemical Analysis of Paints and
14、Paint Materials.Current edition approved June 1, 2011. Published June 2011. Originallyapproved in 1979. Last previous edition approved in 2004 as D3806 98 (2004).DOI: 10.1520/D3806-98R11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at servicea
15、stm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Standardization Documents Order Desk, DODSSP, Bldg. 4,Section D, 700 Robbins Ave., Philadelphia, PA 19111-5098, http:/dodssp.daps.dla.mil.1Copyright ASTM Inte
16、rnational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. Apparatus4.1 Flame Tunnel4(see Fig. 1A)610-mm (two-foot) flametunnel consisting of asbestos-cement board mounted on an ironframework and supplied with natural gas fuel of uniformquality.4.1.1 The framew
17、ork is constructed of 3 by 25 by 25-mm(18 by 1 by 1-in.) angle iron, the top of which provides a 610by 100-mm (24 by 4-in.) specimen holder inclined at 28 to thehorizontal. The framework is mounted on a 250 by 610 by13-mm (10 by 24 by12-in.) steel base. The specimen holder iselevated 185 mm (738 in.
18、) above the base at the lower (fire) endand 480 mm (1878 in.) at the upper (flue) end.4.1.2 The fire end and sides of the tunnel are covered to theextent shown in Fig. 1, with 6-mm (14-in.) asbestos-cementboard5or 6-mm (14-in.) inorganic reinforced-cement board6attached to the inside of the angle ir
19、on framework. The openflue end and the cut-out sides allow a natural draft through thetunnel. Additional air access is provided by a 25-mm (1-in.)hole drilled in the cover at the fire end, centered and 115 mm(412 in.) above the base.4.1.3 An observation window made of a 50-mm (2-in.) widestrip of 3-
20、mm (18-in.) polished heat-resistant sheet glass7islocated just below the specimen holder, extending the fulllength of the tunnel, 610 mm (24 in.). This glass is marked byany appropriate method at 1-in. intervals from 4 to 22 in.A 560by 55 by 2-mm (22 by 214 by116-in.) sheet metal shield isattached a
21、bove the window, slanting downwards at an angle of60 to shield the observation window. The angle iron panelholder is notched along the bottom or supporting lip of theangle at 25-mm (1-in.) intervals to assist in the measurementsof the flame advance.NOTE 1A rule may also be mounted outside the observ
22、ation windowto help measure the flame advancement.4.1.4 A 2.5-mm (332-in.) hole is drilled in the side of thespecimen holder immediately above the center of the burner toallow insertion of a thermocouple.4.1.5 The tunnel should be placed in an area as free fromdrafts as possible with facilities for
23、removal or escape ofcombustion products. (Standard laboratory hood with forceddraft off during test.)4.2 Burner,8215 mm (8.5 in.) high with 40-mm diameter,10-mm thick grid for use with natural gas. The burner is placed57 mm (214 in.) in from the fire end of the tunnel and 25 mm(1 in.) below the bott
24、om side of the sample holder, that is, 30mm (118 in.) from the bottom of the specimen. See Fig. 1.NOTE 2Artificial gas or liquid petroleum (LP) gas may be used, butburners designed for these types of gases must be used.4.3 Ignition Transformer, or other suitable ignition source,to generate a spark t
25、hrough a 2-mm (116-in.) Nichrome wire tothe burner barrel. The transformer is activated by a push-buttontype spark switch.4.4 Gas Supply, of uniform quality controlled by a positive-flow pressure regulatory valve (0 to 152 mm (0 to 6 in.) water)and a gas flowmeter (0.6 to 5.0 SCFH).4.5 Insulating an
26、d Fire Resistant Backing for Test Panels,consisting of 100 by 605-mm (378 by 2378-in.) pieces of13-mm (12-in.) asbestos-cement board or inorganic reinforcedcement board and12-in. steel plate applied one above the otherwith asbestos cement or the inorganic reinforced cement boardplaced directly on to
27、p of the test panel.4.6 Thermocouple9totally shielded (see Note 3), installedthrough the hole in the side of the specimen holder so that itstip rests on the back, cool side, of the test panel.NOTE 3Some commercial tunnels are supplied with more than onethermocouple.4.7 Recording Potentiometer, 0 to
28、300C range.4.8 Audible Timer, set to sound at 15-s intervals to indicatethe time for flame-front measurements.4.9 Constant Temperature and Humidity Room or Cabinet,maintained at 50 6 5 % relative humidity and 23 6 2C (73.56 3.5F).5. Test Panels5.1 Test PanelsSee Table 1 for a list of various woods a
29、ndtheir densities. Wood, 6 by 100 by 605-mm (14 by 378 by2378-in.) close grained, as nearly edge grain as possible andfree from knots and imperfections. The panels should be solidwood with surfaces planed and sanded (see Note 4). Kiln-drytest panels to contain not more than 10 weight % of moistureon
30、 an oven dry basis.NOTE 4Douglas fir, 6.3-mm (14-in.) 3-ply, marinegrade plywoodmay be used upon agreement between manufacturer and user. Asbestos-cement board, steel, or concrete may be used upon agreement betweenmanufacturer and user.5.1.1 Prior to coating, condition test panels for 14 days inthe
31、controlled atmosphere of 50 6 5 % relative humidity and4The sole source of supply of a suitable cabinet and assembly known to thecommittee at this time is Dek-Tron Scientific, 244 East 3rd St., Plainfield, NJ 07060.If you are aware of alternative suppliers, please provide this information to ASTMInt
32、ernational Headquarters. Your comments will receive careful consideration at ameeting of the responsible technical committee,1which you may attend.5The sole source of supply of an asbestos-cement board, transite, known to thecommittee at this time is Manville Corp., Denver CO 80217 If you are aware
33、ofalternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.6The sole source of supply of inorganic reinforced-cement board, #100S and100H, nomina
34、l 1600 to 1760 kg/m3(100 to 110 lb/ft3), known to the committee atthis time is Shameful Corp., 100 Spence Lane, Nashville, TN 37210. If you areaware of alternative suppliers, please provide this information to ASTM Interna-tional Headquarters. Your comments will receive careful consideration at a me
35、etingof the responsible technical committee,1which you may attend.7Quartz or high-silica glass has been found satisfactory for this purpose.8The sole source of supply of a burner, Catalog No. 3902 for artificial gas, orCatalog No. 3900 and 3902 for natural gas and LPgas, respectively, known to theco
36、mmittee at this time is Fisher Scientific Co. If you are aware of alternativesuppliers, please provide this information to ASTM International Headquarters.Your comments will receive careful consideration at a meeting of the responsibletechnical committee,1which you may attend.9The sole source of sup
37、ply of a thermocouple, Megopak Type J, known to thecommittee at this time is Megopak Co. If you are aware of alternative suppliers,please provide this information to ASTM International Headquarters. Your com-ments will receive careful consideration at a meeting of the responsible technicalcommittee,
38、1which you may attend.D3806 98 (2011)2FIG. 1 Flame TunnelD3806 98 (2011)323 6 2C (73.5 6 3.5F) toa9to10%moisture content.Refer to Table 1 for the density and weight per panel of eachlisted wood.5.1.2 Seal the ends of the panels with two coats of varnishconforming to Fed. Spec. TT-V-119 after conditi
39、oning. Alloweach coat of varnish to air-dry 18 to 24 h.6. Calibration Standards6.1 Zero-Flame SpreadAsbestos-cement board, Type Fconforming to Specification C220, 13 by 100 by 605 mm (12by 378 by 2378 in.), conditioned as in 5.1.1.NOTE 5Inorganic reinforced cement board, 6.3-mm (14-in.) thick maybe
40、substituted for asbestos cement.6.2 Fire-Rated StandardA test panel, similar to that usedwith test coatings, coated with Test Method E84 rated paint atthe manufacturers recommended spreading rate and condi-tioned as in Section 7.NOTE 6Do not use paint beyond manufacturers stated shelf life.7. Prepar
41、ation of Test Panels7.1 Thoroughly mix the coating under test by a suitablemeans until it is uniform in composition and consistency. TestMethods D2196 describes a suitable preparation procedure.7.2 Determine the density of the coating in accordance withTest Method D1475 in grams per millilitre (or p
42、ounds pergallon) for calculating the weight of the coating to be appliedto the panel to comply with the specified spreading rate.7.3 Brush apply the coating to conditioned test panels in asuniform a manner as possible to obtain the specified spreadingrate. A suitable procedure appears in Test Method
43、 D344.Application may be by other conventional means and in asmany coats as required to obtain the necessary weight ofcoating, or desired wet or dryfilm thickness.7.4 Calculate the weight of coating to be applied using thefollowing equation:W 5S3783 2378DD144 SR3 454 (1)where:W = weight of applied w
44、et coating, g,D = coating density, lb/gal, andSR= spreading rate, ft2/gal.7.4.1 Use the following equation when metric units areemployed:W 560.5 DSR(2)where:W = weight of applied wet coating, g,D = coating density, g/mL, andSR= spreading rate in m2/L.7.5 Dry the coated panels under standard conditio
45、ns (4.9)until equilibrium weight is obtained, allowing sufficient timefor the complete evaporation of solvents, any curing that mightbe required by the material, and for the attainment of equilib-rium moisture content. Forty-eight hours are normally suffi-cient except for certain coatings that may r
46、equire longerperiods because they trap solvent or contain solvents thatevaporate very slowly.7.6 Apply and cure non-airdrying coatings as recom-mended by the supplier and condition as specified in 7.5.8. Calibration of the Tunnel8.1 Calibrate the tunnel prior to each days operation withthe calibrati
47、on standards described in Section 6.8.1.1 Place the zero flame-spread standard in the holder,smooth side down, and back it with the backing plate (4.5).8.1.2 Open the gas valve and adjust to a pressure of 1.3 kPa(3 oz/in.2) and a constant flow of 38 mL/s (4.8 ft3/h), andactuate the interval timer.NO
48、TE 7These conditions are specified for a natural gas supplyproviding 40 MJ/m3(1055 BTU/ft3). For any other gas supply, adjust flowto provide 1490 J/s (5085 BTU/h).8.1.2.1 When the timer sounds, ignite the burner using theignition transformer. Observe the flame front, measure ininches and record at 1
49、5-s intervals the flame position byaligning the notches in the bottom of the specimen holder withthe markings on the observation window.8.1.3 Record the extreme tip of the flame advance (flamefront) on the panel surface, disregarding flame extending up thetunnel but completely on the angle iron support. After a totaltest period of 4 min, extinguish the burner.8.1.4 Calculate the mean of the three highest consecutivereadings of the flame advance of the zero-flame spreadstandard La.8.2 Repeat the calibration procedure using a fi
