1、Designation: E2965 16aE2965 17 An American National StandardStandard Test Method forDetermination of Low Levels of Heat Release Rate forMaterials and Products Using an Oxygen ConsumptionCalorimeter1This standard is issued under the fixed designation E2965; the number immediately following the design
2、ation indicates the year oforiginal adoption or, in the case of 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.1. Scope*1.1 This fire-test-response standar
3、d provides a procedure for measuring the response of materials that emit low levels of heatrelease when exposed to controlled levels of radiant heating with or without an external igniter.1.2 This test method differs fromTest Method E1354 in that it prescribes a different specific test specimen size
4、, specimen holder,test specimen orientation, a direct connection between the plenum and the top plate of the cone heater assembly to ensure completecollection of all the combustion gases (Fig. 1), and a lower volumetric flow rate for analyses via oxygen consumption calorimetry.It is intended for use
5、 on materials and products that contain only small amounts of combustible ingredients or components, suchas test specimens that yield a peak heat release of 200 kWm2 and total heat release of 15 MJm2.NOTE 1PMMAis typically used to check the general operation of a Cone Calorimeter. PMMAshould not be
6、used with this standard as the heat releaserate is too high.1.3 The rate of heat release is determined by measurement of the oxygen consumption as determined by the oxygenconcentration and the flow rate in the exhaust product stream. The effective heat of combustion is determined from a concomitantm
7、easurement of test specimen mass loss rate, in combination with the heat release rate. Smoke development (an optionalmeasurement) is measured by obscuration of light by the combustion product stream.1.4 Test specimens shall be exposed to initial test heat fluxes generated by a conical radiant heater
8、. External ignition, when used,shall be by electric spark. The test specimen testing orientation is horizontal, independent of whether the end-use applicationinvolves a horizontal or a vertical orientation.1.5 Ignitability is determined as a measurement of time from initial exposure to time of susta
9、ined flaming.1.6 This test method has been developed for use for material and product evaluations, mathematical modeling, design purposes,and development and research. Examples of material test specimens include portions of an end-use product or the variouscomponents used in the end-use product.1.7
10、The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 This standard is used to measure and describe the response of materials, products, or assemblies to heat and flame undercontrolled conditions, but does not by itself incorpor
11、ate all factors required for fire hazard or fire risk assessment of the materials,products, or assemblies under actual fire conditions.1.9 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting thesetests.1.10 This standard does not purpo
12、rt to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use. For specific hazard statements, see Section 7.1.
13、11 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Tra
14、de (TBT) Committee.1 This test method is under the jurisdiction of ASTM Committee E05 on Fire Standards and is the direct responsibility of Subcommittee E05.23 on Combustibility.Current edition approved Sept. 1, 2016Aug. 1, 2017. Published November 2016August 2017. Originally approved in 2015. Last
15、previous edition approved in 2016 asE2965-16.-16a. DOI: 10.1520/E2965-16A.10.1520/E2965-17.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possibl
16、e to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyri
17、ght ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12. Referenced Documents2.1 ASTM Standards:D5865 Test Method for Gross Calorific Value of Coal and CokeE176 Terminology of Fire StandardsE603 Guide for Room Fire ExperimentsE906 Test Method for
18、 Heat and Visible Smoke Release Rates for Materials and Products Using a Thermopile MethodE1354 Test Method for Heat and Visible Smoke Release Rates for Materials and Products Using an Oxygen ConsumptionCalorimeter2.2 ISO StandardsISO 5657-1986 (E) Fire TestsReaction to FireIgnitability of Building
19、MaterialsISO 5725-2 (1994) Accuracy (Trueness and Precision) of Measurement Methods and ResultsPart 2: Basic Method for theDetermination of Repeatability and Reproducibility of a Standard Measurement Method3. Terminology3.1 DefinitionsFor definitions of terms used in this test method, refer to Termi
20、nology E176.3.2 Definitions of Terms Specific to This Standard:3.2.1 effective heat of combustion, nthe amount of heat generated per unit mass lost by a material, product or assembly, whenexposed to specific fire test conditions (contrast gross heat of combustion).3.2.1.1 DiscussionThe effective hea
21、t of combustion depends on the test method, and is determined by dividing the measured heat release by the massloss during a specified period of time under the specified test conditions. Typically, the specified fire test conditions are providedby the specifications of the fire test standard that ci
22、tes effective heat of combustion as a quantity to be measured. For certain firetest conditions, involving very high heat and high oxygen concentrations under high pressure, the effective heat of combustion willapproximate the gross heat of combustion. More often, the fire test conditions will repres
23、ent or approximate certain real fireexposure conditions, and the effective heat of combustion is the appropriate measure. Typical units are kJ/g or MJ/kg.FIG. 1 Modified Cone CalorimeterE2965 1723.2.2 gross heat of combustion, nthe maximum amount of heat per unit mass that theoretically can be relea
24、sed by thecombustion of a material, product, or assembly; it can be determined experimentally and only under conditions of high pressureand in pure oxygen (contrast effective heat of combustion).3.2.3 heat flux, nheat transfer to a surface per unit area, per unit time (see also initial test heat flu
25、x).3.2.3.1 DiscussionThe heat flux from an energy source, such as a radiant heater, can be measured at the initiation of a test (such as Test Method E1354or Test Method E906) and then reported as the incident heat flux, with the understanding that the burning of the test specimen cangenerate additio
26、nal heat flux to the specimen surface. The heat flux can also be measured at any time during a fire test, for exampleas described in Guide E603, on any surface, and with measurement devices responding to radiative and convective fluxes. Typicalunits are kW/m2, kJ/(s m2), W/cm2, or BTU/(s ft2).3.2.4
27、heat release rate, nthe heat evolved from the specimen, per unit of time.3.2.5 ignitability, nthe propensity to ignition, as measured by the time to sustained flaming, in seconds, at a specified heatingflux.3.2.6 initial test heat flux, nthe heat flux set on the test apparatus at the initiation of t
28、he test (see also heat flux).3.2.6.1 DiscussionThe initial test heat flux is the heat flux value commonly used when describing or setting test conditions.3.2.7 net heat of combustion, nthe oxygen bomb (see Test Method D5865) value for the heat of combustion, corrected forgaseous state of product wat
29、er.3.2.7.1 DiscussionThe net heat of combustion differs from the gross heat of combustion, in that the former assesses the heat per unit mass generatedfrom a combustion process that ends with water in the gaseous state, while the latter ends with water in the liquid state.3.2.8 orientation, nthe pla
30、ne in which the exposed face of the specimen is located during testing, either vertical or horizontalfacing up.3.2.9 oxygen consumption principle, nthe expression of the relationship between the mass of oxygen consumed duringcombustion and the heat released.3.2.10 smoke obscuration, nreduction of li
31、ght transmission by smoke, as measured by light attenuation.3.2.11 sustained flaming, nexistence of flame on or over most of the specimen surface for periods of at least 4 s.3.2.11.1 DiscussionFlaming of less than 4 s duration is identified as flashing or transitory flaming.3.3 Symbols:As = nominal
32、test specimen exposed surface area, 0.0225m2.C = calibration constant for oxygen consumption analysis, m1/2 kg 1/2 K1/2.hc = net heat of combustion, kJ/kg.hc,eff = effective heat of combustion, kJ/kg.I = actual beam intensity.Io = beam intensity with no smoke.k = smoke extinction coefficient, m-1.L
33、= extinction beam path length, m.m = test specimen mass, kg.mf = final test specimen mass, kg.mi = initial test specimen mass, kg.m = test specimen mass loss rate, kg/s.P = orifice meter pressure differential, Pa.Qtot = total heat released, kJ/m2 (Note that kJ kWs).q = heat release rate, kW.q = heat
34、 release rate per unit area, kW/m2.E2965 173qmax = maximum heat release rate per unit area (kW/m2).q180 = average heat release rate, per unit area, over the time period starting at tig and ending 180 s later (kW/m2).r = repeatability (the units are the same as for the variable being characterized).R
35、 = reproducibility (the units are the same as for the variable being characterized).rO = stoichiometric oxygen/fuel mass ratio ().sr = sample-based standard deviation estimate for repeatability (same units as r).sR = sample-based standard deviation estimate for reproducibility (same units as R).t =
36、time, s.td = oxygen analyzer delay time, s.tig = time to sustained flaming (s). = density (kg/m3).t = sampling time interval, s.Te = absolute temperature of gas at the orifice meter, K.V = volume exhaust flow rate, measured at the location of the laser photometer, m3/s.XO2 = oxygen analyzer reading,
37、 mole fraction O2 ().XO20 = initial value of oxygen analyzer reading ().XO21 = oxygen analyzer reading, before delay time correction ().f = specific extinction area, for smoke, m2/kg.r = repeatability standard deviation (same units as r).R = reproducibility standard deviation (same units as R).4. Su
38、mmary of Test Method4.1 This test method is based on the observation that, generally, the net heat of combustion is directly related to the amount ofoxygen required for combustion. The relationship, known as the oxygen consumption principle, is that approximately 13.1 103kJ of heat are released per
39、1 kg of oxygen consumed. Test specimens in the test are burned in ambient air conditions, while beingsubjected to a predetermined initial test heat flux. In the test, the test specimens are exposed to a pre-determined initial test heatflux, either with or without the added use of a spark igniter. Th
40、e primary measurements are oxygen concentrations and exhaust gasflow rate, which are used to determine heat release rate and total heat released.Additional measurements include the mass-loss rateof the test specimen, the time to sustained flaming and (optionally) smoke obscuration, or as required in
41、 the relevant material orperformance standard.4.2 Prior to testing any material using this test method, assurance shall be given to the test laboratory that the material to betested will not generate excessive heat when tested, for example by complying with 4.2.1 or with 4.2.2.4.2.1 The material sha
42、ll be tested to Test Method E1354 at the same initial test heat flux and yield a peak heat release rate of200 kW/m2 and a total heat release of 15 MJ/m2, as required in 11.1.4.2.2 In lieu of conducting the test with Test Method E1354, the test requestor is permitted to provide alternate evidence tha
43、tthe material to be tested will meet the heat release requirements of 4.2, as required in 11.2.5. Significance and Use5.1 This test method is used primarily to determine the heat evolved in, or contributed to, a fire involving materials or productsthat emit low levels of heat release. The recommende
44、d use for this test method is for materials with a total heat release ratemeasured of less than 10 MJ over the first 20 min test period, and which do not give peak heat release rates of more than200 kWm2 for periods extending more than 10 s. Also included is a determination of the effective heat of
45、combustion, mass lossrate, the time to sustained flaming, and (optionally) smoke production. These properties are determined on small size testspecimens that are representative of those in the intended end use.5.2 This test method is applicable to various categories of products and is not limited to
46、 representing a single fire scenario.5.3 This test method is not applicable to end-use products that do not have planar, or nearly planar, external surfaces.6. Apparatus6.1 General:6.1.1 The test apparatus shall be as described inTest Method E1354 with the changes described below. Fig. 1 shows an ov
47、erviewof the apparatus.6.1.2 All dimensions given in the figures that are followed by an asterisk are mandatory, and shall be followed within nominaltolerances of 61 mm, unless otherwise specified.6.1.3 Additional details describing features and operation of the test apparatus are given in Ref (2).6
48、.2 Conical Heater:6.2.1 The heater shall be similar to that used in Test Method E1354, but it shall be of a larger format and constructed such thatit is capable of producing irradiance on the surface of the test specimen of up to 80 kW/m2. The irradiance shall be uniform withinthe central 100 mm by
49、100 mm area of the exposed test specimen surface, to within 62 % and within 63 % over the entire surfaceE2965 174of the specimen. The heater shall consist of electrical heater rods, tightly wound into the shape of a truncated cone. The heater shallbe encased on the outside with a double-wall stainless steel cone, packed with a refractory fiber material of approximately 100kg/m3 density.6.3 Test Specimen Mounting:6.3.1 The specimen holder is shown in Fig. 2. The bottom shall be constructed of 2.4 mm nominal stainless steel, a
