1、Designation: E800 14 An American National StandardStandard Guide forMeasurement of Gases Present or Generated During Fires1This standard is issued under the fixed designation E800; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, th
2、e 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. Scope1.1 Analytical methods for
3、 the measurement of carbonmonoxide, carbon dioxide, oxygen, nitrogen oxides, sulfuroxides, carbonyl sulfide, hydrogen halides, hydrogen cyanide,aldehydes, and hydrocarbons are described, along with sam-pling considerations. Many of these gases may be present inany fire environment. Several analytica
4、l techniques are de-scribed for each gaseous species, together with advantages anddisadvantages of each. The test environment, samplingconstraints, analytical range, and accuracy often dictate use ofone analytical method over another.1.2 These techniques have been used to measure gasesunder fire tes
5、t conditions (laboratory, small scale, or full scale).With proper sampling considerations, any of these methodscould be used for measurement in most fire environments.1.3 This document is intended to be a guide for investigatorsand for subcommittee use in developing standard test methods.A single an
6、alytical technique has not been recommended forany chemical species unless that technique is the only oneavailable.1.4 The techniques described herein determine the concen-tration of a specific gas in the total sample taken. Thesetechniques do not determine the total amount of fire gases thatwould b
7、e generated by a specimen during conduct of a fire test.1.5 This standard is used to measure and describe theresponse of materials, products, or assembles to heat and flameunder controlled conditions but does not by itself incorporateall factors required for fire hazard or fire risk assessment of th
8、ematerials, products, or assemblies under actual fire conditions.1.6 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 practices and determine the appl
9、ica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D123 Terminology Relating to TextilesD1356 Terminology Relating to Sampling and Analysis ofAtmospheresD2036 Test Methods for Cyanides in WaterD2777 Practice for Determination of Precision and Bias ofApplicab
10、le Test Methods of Committee D19 on WaterD3612 Test Method for Analysis of Gases Dissolved inElectrical Insulating Oil by Gas ChromatographyD6348 Test Method for Determination of Gaseous Com-pounds by Extractive Direct Interface Fourier TransformInfrared (FTIR) SpectroscopyD6696 Guide for Understand
11、ing Cyanide SpeciesD6888 Test Method for Available Cyanide with LigandDisplacement and Flow InjectionAnalysis (FIA) UtilizingGas Diffusion Separation and Amperometric DetectionD7295 Practice for Sampling and Determination of Hydro-gen Cyanide (HCN) in Combustion Effluents and OtherStationary Sources
12、D7365 Practice for Sampling, Preservation and MitigatingInterferences in Water Samples for Analysis of CyanideE84 Test Method for Surface Burning Characteristics ofBuilding MaterialsE176 Terminology of Fire StandardsE535 Practice for Preparation of Fire-Test-Response Stan-dardsE603 Guide for Room Fi
13、re ExperimentsE662 Test Method for Specific Optical Density of SmokeGenerated by Solid Materials3. Terminology3.1 DefinitionsDefinitions used in this guide are in accor-dance with Terminology D123, Terminology D1356, Terminol-ogy E176, and Practice E535 unless otherwise indicated.3.2 Definitions of
14、Terms Specific to This Standard:3.2.1 batch samplingsampling over some time period insuch a way as to produce a single test sample for analysis.1This guide is under the jurisdiction ofASTM Committee E05 on Fire Standardsand is the direct responsibility of Subcommittee E05.21 on Smoke and CombustionP
15、roducts.Current edition approved Nov. 15, 2014. Published December 2014. Originallyapproved in 1981. Last previous edition approved in 2007 as E800 07. DOI:10.1520/E0800-14.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For A
16、nnual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States13.2.2 combustion products, nairborne effluent from amaterial undergoing co
17、mbustion; this may also include pyro-lysates.3.2.2.1 Discussioncombustion products without mass,such as heat or other radiation, are not addressed in this guide.3.2.3 fire test, na procedure, not necessarily a standard testmethod, in which the response of materials to heat or flame, orboth, under co
18、ntrolled conditions is measured or otherwisedescribed.3.2.4 sample integritythe unimpaired chemical composi-tion of a test sample upon the extraction of said test sample foranalysis.3.2.5 samplinga process whereby a test sample is ex-tracted from a fire test environment.3.2.6 test samplea representa
19、tive part of the experimentalenvironment (gases, liquids, or solids), for purposes of analy-sis.4. Significance and Use4.1 Because of the loss of life in fires from inhalation of firegases, much attention has been focused on the analyses of thesespecies. Analysis has involved several new or modified
20、methods, since common analytical techniques have oftenproven to be inappropriate for the combinations of variousgases and low concentrations existing in fire gas mixtures.4.2 In the measurement of fire gases, it is imperative to useprocedures that are both reliable and appropriate to the uniqueatmos
21、phere of a given fire environment. To maximize thereliability of test results, it is essential to establish the follow-ing:4.2.1 That gaseous samples are representative of the com-positions existing at the point of sampling,4.2.2 That transfer and pretreatment of samples occur with-out loss, or with
22、 known efficiency, and4.2.3 That data provided by the analytical instruments areaccurate for the compositions and concentrations at the point ofsampling.4.3 This document includes a comprehensive survey thatwill permit an individual, technically skilled and practiced inthe study of analytical chemis
23、try, to select a suitable techniquefrom among the alternatives. It will not provide enoughinformation for the setup and use of a procedure (this infor-mation is available in the references).4.4 Data generated by the use of techniques cited in thisdocument should not be used to rank materials for reg
24、ulatorypurposes.5. Sampling5.1 More errors in analysis result from poor and incorrectsampling than from any other part of the measurement process(1, 2).3It is therefore essential to devote special attention tosampling, sample transfer, and pretreatment aspects of theanalysis procedures.5.2 Planning
25、for AnalysisDefinitive answers should besought and provided to the following questions during theplanning stage: (1) Why is the sampling (analysis) beingperformed? (2) What needs to be measured? (3) Where willsamples be taken? (4) When does one sample? (5) How aresamples collected? (3).5.2.1 All asp
26、ects of sampling and analysis relate to thefundamental reasons for performing the analysis. Analysis ofcombustion products is normally performed for one of thefollowing reasons: for research on the composition of thegases; to relate directly to flammability, smoke generation,toxic or irritant effect
27、s; to study mechanisms of combustion; orfor development of test equipment. The experimenter shoulddecide exactly what type of information the analysis mustprovide. The necessary detection limits, acceptable errors, andpossible or tolerable interferences must be determined.5.2.2 A representative samp
28、le must be obtained; however,sampling must not interfere with the test (for example, sam-pling could alter the atmosphere in an animal toxicity experi-ment or in a smoke measurement device). The size and shapeof the test chamber affects the possible location and number ofsampling probes.5.2.3 Single
29、 or cumulative samples may be adequate formany requirements; however, a continuous monitor may bedesirable for the determination of concentration-timedependence, or in the case of analysis of reactive species (forexample, hydrochloric acid (HCl).5.2.4 Collection and transport of samples must be acco
30、m-plished in such a way that the analyses properly reflect thenature and concentration of species in the combustion gasstream. Heated sampling lines made from an inert material areoften required. Direct sampling and immediate analysis arepreferable to retention of the sample for later analysis. Filt
31、ra-tion of combustion gases prior to analysis may be necessary forsome applications, but may be totally incorrect for other cases(see 5.9).5.3 Test SystemsMany devices of various sizes can gen-erate “fire gases for analysis (4,(5). These systems includelarge-scale facilities (fire situations simulat
32、ed on a 1:1 scale(see Guide E603 and Ref (6); large laboratory-scale tests (forexample, Test Method E84); laboratory-scale chambers (forexample, Test Method E662 (7, 8); and microcombustionfurnace or tube furnace assemblies (2,(9).5.3.1 In general, the combustion devices (test chambers) fallinto thr
33、ee categories:(1) closed chambers (for example, Test Method E662);(2) open chambers (for example, a full-scale room burn);(3) flow-through systems (for example, Test Method E84).5.3.2 Different test chamber sizes and configurations requiredifferent methods of sampling and analysis. Appropriate ana-l
34、ytical procedures and equipment must be selected. In afull-scale fire experiment the sampling frequency and detectionlevel and accuracy may not need to be the same as in a smalllaboratory-scale experiment.5.4 Reactivity of Fire Gases:5.4.1 Fire gases to be analyzed range from relatively inertand vol
35、atile substances, such as carbon monoxide (CO) andcarbon dioxide (CO2), to reactive acid gases such as hydrogen3The boldface numbers in parentheses refer to the list of references appended tothis standard.E800 142fluoride (HF), HCl, and hydrogen bromide (HBr). Otherspecies frequently determined are
36、oxygen, the sulfur-oxidespecies sulfur dioxide (SO2) and sulfur trioxide (SO3); thenitrogen-containing species hydrogen cyanide (HCN), nitricoxide (NO), and nitrogen dioxide (NO2); and hydrocarbonsand partially oxidized hydrocarbons.5.4.2 The following potential problems must be avoided orminimized
37、by proper design of the sampling system and choiceof materials of construction:(1) Reaction of the gaseous products with materials used insampling lines and test equipment that could lead to loss ofsample and potential equipment failure;(2) Adsorption, absorption, or condensation of gaseousproducts
38、in the sampling system or on particles trapped in thefiltration system;(3) Reaction among species present in the gaseous sample;(4) Interferences caused by species in the sample, otherthan the product being analyzed, that respond to the analyticalmethod.5.5 Sampling FrequencyThe frequency of samplin
39、g isbased primarily on the information sought. Most requirementswill be met by one of the following three sampling modes:(1) The quantity formed during the experiment is deter-mined by collecting one time-integrated sample (2);(2) The concentration is determined at a limited number oftime points dur
40、ing the experiment (10);(3) The concentration is determined either continuously orwith sufficient frequency to represent it as a function of time (6,8, 10, 11).5.5.1 The two techniques used most commonly in the pasthave been the single, integrated sample and sampling at fixedtime intervals. However,
41、 techniques for continuous analysis ofcertain species are now readily available (CO, CO2, andoxygen (O2); while continuous analysis of other compoundsof interest have been reported (12).5.5.2 The integrated sampling technique entails collectionof all the products (or a continuous sample from the gas
42、stream) into an unreactive sampling bag such as polytetrafluo-roethylene (PTFE) or absorption of the species of interest in anappropriate solvent in an impinger for the duration of theexperiment.Analyses are then performed on the contents of thebag or trapping medium (9). Water-soluble species such
43、as HClor HBr have been collected in solution impingers over theduration of the experiment, enabling analysis of the “inte-grated” sample. The gas flow rate through the impinger and theliquid volume determine the buildup of acid gas in the solution(the solubility of the species at the given gas flow
44、rate shouldbe verified). The integrated sampling techniques provide eitherthe “average” concentration of the particular species over theduration of the test or, for certain flow-through test procedures,a measure of the total amount of that species produced in theexperiment. In this latter case, a to
45、tal gas flow measurement isrequired.5.5.3 Continuous or frequent, periodic sampling is oftendesirable. This limits further reaction of reactive species (suchas HCl, HBr, and HCN), and is useful for studies of time-dependent, cumulative effects of toxic gases (such as CO) onanimals.5.5.4 Samples of c
46、ombustion gas can be collected sequen-tially for subsequent instrumental analysis. An electricallyactivated multiport stream selection valve or a manifold ofsolenoid valves can be used to sequentially divert the combus-tion gas into a series of gas collection devices. This collectionprocedure can be
47、 automated by using a valve sequence timer ora multipole relay timer (13, 14).5.5.5 For noncontinuous sampling of combustion gases, thefrequency of sampling is often determined by the instrumen-tation. For example, using gas chromatography, sampling willbe dependent on the residence time of species
48、in the instru-ment. Sampling of species at time intervals using gas syringes,plastic sampling bags, sorption tubes, or the like, with analysesto be performed later, is not dependent on analysis time.5.5.6 The volume of frequent or continuous gas samplesremoved must not significantly affect the conce
49、ntration ofremaining species. In small test chambers and someflowthrough systems, the volume of gas available for samplingis limited.5.6 Sampling Sites:5.6.1 The number and the locations of sampling sites aredetermined by the extent of analytical information sought andby the configuration of the test chamber (15, 16). To obtainrepresentative samples from an NBS smoke density chamber,intake ports in one study (11) were located at three heightsinside the chamber. The sample streams were then combinedbefore being introduced into the analyzers. Previous experi-ments ha
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