1、Designation: E662 18 An American National StandardStandard Test Method forSpecific Optical Density of Smoke Generated by SolidMaterials1This standard is issued under the fixed designation E662; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、 revision, 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This fir
3、e-test-response standard covers determination ofthe specific optical density of smoke generated by solidmaterials and assemblies mounted in the vertical position inthicknesses up to and including 1 in. (25.4 mm).1.2 Measurement is made of the attenuation of a light beamby smoke (suspended solid or l
4、iquid particles) accumulatingwithin a closed chamber due to nonflaming pyrolytic decom-position and flaming combustion.1.3 Results are expressed in terms of specific optical densitywhich is derived from a geometrical factor and the measuredoptical density, a measurement characteristic of the concent
5、ra-tion of smoke.1.4 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.5 This standard measures and describes the response ofmaterials, p
6、roducts, or assemblies to heat and flame undercontrolled conditions, but does not by itself incorporate allfactors required for fire hazard or fire risk assessment of thematerials, products or assemblies under actual fire conditions.1.6 This standard does not purport to address all of thesafety conc
7、erns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accor-dance with
8、internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2
9、C1186 Specification for Flat Fiber-Cement SheetsC1288 Specification for Fiber-Cement Interior SubstrateSheetsD2843 Test Method for Density of Smoke from the Burningor Decomposition of PlasticsE176 Terminology of Fire StandardsE662 Test Method for Specific Optical Density of SmokeGenerated by Solid M
10、aterials3. Terminology3.1 DefinitionsFor definitions of terms found in this testmethod refer to Terminology E176.4. Summary of Test Method4.1 This test method employs an electrically heated radiant-energy source mounted within an insulated ceramic tube andpositioned so as to produce an irradiance le
11、vel of 2.2 Btu/sft2(2.5 W/cm2) averaged over the central 1.5-in. (38.1-mm)diameter area of a vertically mounted specimen facing theradiant heater. The nominal 3 by 3-in. (76.2 by 76.2-mm)specimen is mounted within a holder which exposes an areameasuring 2916 by 2916 in. (65.1 by 65.1 mm). The holder
12、 isable to accommodate specimens up to 1 in. (25.4 mm) thick.This exposure provides the nonflaming condition of the test.4.2 For the flaming condition, a six-tube burner is used toapply a row of equidistant flamelets across the lower edge ofthe exposed specimen area and into the specimen holdertroug
13、h. This application of flame in addition to the specifiedirradiance level from the heating element constitutes theflaming combustion exposure.4.3 The test specimens are exposed to the flaming andnonflaming conditions within a closed chamber. A photometricsystem with a vertical light path is used to
14、measure the varying1This test method is under the jurisdiction of ASTM Committee E05 on FireStandards and is the direct responsibility of Subcommittee E05.21 on Smoke andCombustion Products.Current edition approved Dec. 1, 2018. Published December 2018. Originallyapproved in 1979. Last previous edit
15、ion approved in 2017 as E662 17a. DOI:10.1520/E0662-18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.*A Sum
16、mary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization establishe
17、d in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1light transmission as smoke accumulates. The light transmit-tance measurements are used to calculate specific
18、opticaldensity of the smoke generated during the time period to reachthe maximum value.35. Significance and Use5.1 This test method provides a means for determining thespecific optical density of the smoke generated by specimens ofmaterials and assemblies under the specified exposure condi-tions. Va
19、lues determined by this test are specific to thespecimen or assembly in the form and thickness tested and arenot to be considered inherent fundamental properties of thematerial tested. Thus, it is likely that closely repeatable orreproducible experimental results are not to be expected fromtests of
20、a given material when specimen thickness, density, orother variables are involved.5.2 The photometric scale used to measure smoke by thistest method is similar to the optical density scale for humanvision. However, physiological aspects associated with visionare not measured by this test method. Cor
21、relation with mea-surements by other test methods has not been established.45.3 At the present time no basis is provided for predictingthe density of smoke generated by the materials upon exposureto heat and flame under other fire conditions.5.4 The test method is of a complex nature and the dataobt
22、ained are sensitive to variations which in other test methodsmight be considered to be insignificant (see Section 6). Aprecision statement based on the results of a roundrobin test bya prior draft version of this test method is given in 14.15.5 In this procedure, the specimens are subjected to one o
23、rmore specific sets of laboratory test conditions. If different testconditions are substituted or the end-use conditions arechanged, it is not always possible by or from this test methodto predict changes in the fire-test-response characteristicsmeasured. Therefore, the results are valid only for th
24、e fire testexposure conditions described in this procedure.6. Limitations6.1 If during the test of one or more of the three replicatesamples there occurs such unusual behavior as (1) the speci-men falling out of the holder, (2) melted material overflowingthe sample holder trough, (3) self-ignition i
25、n the pyrolysismode, (4) extinguishment of the flame tiplets (even for a shortperiod of time), or (5) a specimen being displaced from thezone of controlled irradiance, then an additional three samplesof the identical preconditioned materials shall be tested in thetest mode in which the unusual behav
26、ior occurred. Dataobtained from the improper tests noted above shall not beincorporated in the averaged data but the occurrence shall bereported. The test method is not suitable if more than three ofthe six replicates tested show these characteristics.6.2 The test method has proven sensitive to smal
27、l variationsin sample geometry, surface orientation, thickness (eitheroverall or individual layer), weight, and composition. It is,therefore, critical that the replicate samples be cut, sawed, orblanked to identical sample areas, 3 by 3, +0, 0.03 in. (76.2by 76.2, +0, 0.8 mm), and that records be ke
28、pt of therespective weights with the individual test data. It is feasiblethat evaluation of the obtained data together with the individualweights will assist in assessing the reasons for any observedvariability in measurements. Preselection of samples withidentical thickness or weight, or both, are
29、potential methods toreduce the variability but are likely to not be truly indicative ofthe actual variability to be expected from the material asnormally supplied.6.3 The results of the test apply only to the thickness of thespecimen as tested. There is no common mathematical formulato calculate the
30、 specific optical density of one thickness of amaterial when the specific optical density of another thicknessof the same material is known.6.4 The test method is sensitive to small variations of theposition of the specimen and radiometer relative to the radiantheat source.6.5 It is critical to clea
31、n the test chamber, and to removeaccumulated residues from the walls when changing from onetest material to another, to ensure that chemical or physicalrecombination with the effluents or residues produced does notaffect the data obtained. Even when testing the same material,excessive accumulations
32、of residue shall not be permitted tobuild up since ruggedness tests have indicated that suchaccumulations serve as additional insulators tending to reducenormally expected condensation of the aerosol, thereby raisingthe measured specific optical density.6.6 With resilient samples, take extreme care
33、to ensure thateach replicate sample in its aluminum foil wrapper is installedso that each protrudes identically through the front sampleholder opening. Unequal protrusion will subject the samples todifferent effective irradiances and to slightly different ignitionexposures. Excessive protrusion of s
34、pecimens has the potentialto cause drips or for the specimen to sag onto the burner,clogging the flame jets and thereby invalidating the test.6.7 The measurements obtained have also proven sensitiveto small differences in conditioning (see Section 9). Manymaterials such as carpeting and thick sectio
35、ns of wood,plastics, or plywood require long periods to attain equilibrium(constant weight) even in a forced-draft humidification cham-ber.7. Apparatus7.1 Fig. 1 shows examples of the test apparatus, with adetailed description contained in the remainder of Section 7and in Annex A2. The apparatus sha
36、ll include the following:3Additional parameters, such as the maximum rate of smoke accumulation, timeto a fixed optical density level, or a smoke obscuration index provide potentiallyuseful information. See Appendix X1.4Other test methods for measuring smoke available at the time of the publica-tion
37、s referenced have been reviewed and summarized in “The Control of Smoke inBuilding FiresAState of theArt Review.” Materials Research and Standards,Vol42, April 1971, pp. 1623 and “A Report on Smoke Test Methods,” ASTMStandardization News, August 1976, pp. 1826.E662 1827.1.1 Test ChamberAs shown in F
38、ig. 1, the test chambershall be fabricated from laminated panels5to provide insidedimensions of 36 by 24 by 36 618 in. (914 by 610 by 914 63 mm) for width, depth, and height, respectively. The interiorsurfaces shall consist of porcelain enameled metal, or othercoated metal, which shall be resistant
39、to chemical attack andcorrosion, and suitable for periodic cleaning. Sealed windowsshall be provided to accommodate a vertical photometricsystem. All other chamber penetrations shall be sealed. Whenall openings are closed, the chamber shall be capable of5Commercially available panels of porcelain-en
40、ameled steel (interior surface)permanently laminated to an asbestos-magnesia core and backed with galvanizedsteel (exterior surface), total thickness316 in. (9.6 mm), have been found suitable.APhotomultiplier tube housing NFlowmeter shutoff valvesBChamber OSample mover knobCBlow-out panel (in floor
41、of chamber) PLight source switchDHinged door with window QLight source voltage jacksEExhaust vent control RLine switchFRadiometer output jacks SBase cabinetGTemperature (wall) indicator TIndicating lampsHAutotransformer UMicrophotometer (photomultiplier)IFurnace switch VOptical system rodsJVoltmeter
42、 (furnace) WOptical system floor windowKFuse holder (furnace) XExhaust vent damperLRadiometer air flowmeter YInlet vent damperMGas and air (burner) flowmeter ZAccess portsFIG. 1 Smoke Density Chamber AssemblyE662 183developing and maintaining positive pressure during testperiods, in accordance with
43、11.12. The air-tightness of thechamber shall be tested at least one per test day in accordancewith 11.2.7.1.1.1 If the interior wall surfaces become corroded or thecoating starts to peel off, users shall repair the damaged areausing any suitable coating material, installed to the coatingmanufacturer
44、s instructions.NOTE 1Some high temperature paints have been found satisfactoryfor this purpose.7.1.1.2 Fit the chamber with a safety blow-out panel,consisting of a sheet of aluminum foil of thickness not greaterthan 1.63 103in. (0.04 mm) and having a minimum area of125 in.2(80 600 mm2), fastened in
45、such a way as to provide anairtight seal.7.1.2 Radiant Heat FurnaceAs shown in Fig. 2,anelectric furnace with a 3-in. (76.2-mm) diameter opening shallbe used to provide a constant irradiance on the specimensurface. The furnace shall be located along the centerlineequidistant between the front and ba
46、ck of the chamber, with theopening facing toward and about 12 in. (305 mm) from theright wall. The centerline of the furnace shall be about 734 in.(195 mm) above the chamber floor. The furnace control systemshall maintain the required irradiance level, under steady-stateconditions with the chamber d
47、oor closed, of 2.20 6 0.04Btu/ft2s (2.50 6 0.05 W/cm2) for 20 min.7.1.2.1 The control system shall consist of one of thefollowing:(1) An autotransformer and a voltmeter for monitoring theelectrical input. Where line voltage fluctations exceed 62.5 V,a constant voltage transformer is required to main
48、tain theprescribed irradiance level.AStainless steel tube GStainless steel spacersBFront insulating ring HStainless steel reflectors (3)CCeramic tube JCenter insulating diskDHeater/plate 525 W KInsulating spacer ringEStainless steel mounting screw LRear insulating diskFInsulating gasket MSheet metal
49、 screw (2)PHeater leads/porcelain beadsFIG. 2 Furnace SectionE662 184(2) An electronic temperature controller capable of main-taining furnace temperature 6 37.4F (3C). If this option isused, a thermocouple for monitoring the furnace temperatureshall be required, and the furnace temperature shall be dis-played on the controller or software.7.1.3 Specimen HolderSpecimen holders shall conform inshape and dimension to that shown in Fig. 3 and be fabricatedto expose a 2916 by 2916-in. (65.1 by 65.1-mm) specimen area.Also
