Standard Guide for Measurement of Gases Present or Generated During Fires

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1.1 Analytical methods for the measurement of carbon monoxide, carbon dioxide, oxygen, nitrogen oxides, sulfur oxides, carbonyl sulfide, hydrogen halides, hydrogen cyanide, aldehydes, and hydrocarbons are described, along with sampling considerations. Many of these gases may be present in any fire environment. Several analytical techniques are described for each gaseous species, together with advantages and disadvantages of each. The test environment, sampling constraints, analytical range, and accuracy often dictate use of one analytical method over another.
1.2 These techniques have been used to measure gases under fire test conditions (laboratory, small scale, or full scale). With proper sampling considerations, any of these methods could be used for measurement in most fire environments.
1.3 This document is intended to be a guide for investigators and for subcommittee use in developing standard test methods. A single analytical technique has not been recommended for any chemical species unless that technique is the only one available.
1.4 The techniques described herein determine the concentration of a specific gas in the total sample taken. These techniques do not determine the total amount of fire gases that would be generated by a specimen during conduct of a fire test.
1.5 This standard is used to measure and describe the response of materials, products, or assembles to heat and flame under controlled conditions but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions
1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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Publication Date
09-Oct-2001
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ASTM E800-99 - Standard Guide for Measurement of Gases Present or Generated During Fires
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NOTICE: This standard has either been superseded and replaced by a new version or discontinued.
Contact ASTM International (www.astm.org) for the latest information.
Designation: E 800 – 99 An American National Standard
AMERICAN SOCIETY FOR TESTING AND MATERIALS
100 Barr Harbor Dr., West Conshohocken, PA 19428
Reprinted from the Annual Book of ASTM Standards. Copyright ASTM
Standard Guide for
Measurement of Gases Present or Generated During Fires
This standard is issued under the fixed designation E 800; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope D 1356 Terminology Relating to Sampling and Analysis of
Atmospheres
1.1 Analytical methods for the measurement of carbon
D 3162 Test Method for Carbon Monoxide in the Atmo-
monoxide, carbon dioxide, oxygen, nitrogen oxides, sulfur
sphere (Continuous Measurement by Nondispersive Infra-
oxides, carbonyl sulfide, hydrogen halides, hydrogen cyanide,
red Spectrometry)
aldehydes, and hydrocarbons are described, along with sam-
E 84 Test Method for Surface Burning Characteristics of
pling considerations. Many of these gases may be present in
Building Materials
any fire environment. Several analytical techniques are de-
E 176 Terminology Relating to Fire Standards
scribed for each gaseous species, together with advantages and
E 535 Practice for Preparation of Fire-Test-Response Stan-
disadvantages of each. The test environment, sampling con-
dards
straints, analytical range, and accuracy often dictate use of one
E 603 Guide for Room Fire Experiments
analytical method over another.
E 662 Test Method for Specific Optical Density of Smoke
1.2 These techniques have been used to measure gases
Generated by Solid Materials
under fire test conditions (laboratory, small scale, or full scale).
With proper sampling considerations, any of these methods
3. Terminology
could be used for measurement in most fire environments.
3.1 Definitions—Definitions used in this guide are in accor-
1.3 This document is intended to be a guide for investigators
dance with Terminology D 123, Terminology D 1356, Termi-
and for subcommittee use in developing standard test methods.
nology E 176, and Practice E 535 unless otherwise indicated.
A single analytical technique has not been recommended for
3.2 Definitions of Terms Specific to This Standard:
any chemical species unless that technique is the only one
3.2.1 batch sampling—sampling over some time period in
available.
such a way as to produce a single test sample for analysis.
1.4 The techniques described herein determine the concen-
3.2.2 combustion products—airborne effluent from a mate-
tration of a specific gas in the total sample taken. These
rial undergoing combustion; this may also include pyrolysates.
techniques do not determine the total amount of fire gases that
3.2.3 fire test, n—a procedure, not necessarily a standard
would be generated by a specimen during conduct of a fire test.
test method, in which the response of materials to heat or
1.5 This standard is used to measure and describe the
flame, or both, under controlled conditions is measured or
response of materials, products, or assembles to heat and flame
otherwise described.
under controlled conditions but does not by itself incorporate
3.2.4 sample integrity—the unimpaired chemical composi-
all factors required for fire hazard or fire risk assessment of the
tion of a test sample upon the extraction of said test sample for
materials, products, or assemblies under actual fire conditions.
analysis.
1.6 This standard does not purport to address all of the
3.2.5 sampling—a process whereby a test sample is ex-
safety concerns, if any, associated with its use. It is the
tracted from a fire test environment.
responsibility of the user of this standard to establish appro-
3.2.6 test sample—a representative part of the experimental
priate safety and health practices and determine the applica-
environment (gases, liquids, or solids), for purposes of analy-
bility of regulatory limitations prior to use.
sis.
2. Referenced Documents
4. Significance and Use
2.1 ASTM Standards:
2 4.1 Because of the loss of life in fires from inhalation of fire
D 123 Terminology Relating to Textiles
gases, much attention has been focused on the analyses of these
species. Analysis has involved several new or modified meth-
This guide is under the jurisdiction of ASTM Committee E-5 on Fire Standards
ods, since common analytical techniques have often proven to
and is the direct responsibility of Subcommittee E05.21 on Smoke and Combustion
Products.
Current edition approved March 10, 1999. Published June 1999. Originally
published as E 800 – 81. Last previous edition E 800 – 95. Annual Book of ASTM Standards, Vol 11.03.
2 4
Annual Book of ASTM Standards, Vol 07.01. Annual Book of ASTM Standards, Vol 04.07.
E 800
be inappropriate for the combinations of various gases and low dence, or in the case of analysis of reactive species (for
concentrations existing in fire gas mixtures. example, hydrochloric acid (HCl).
4.2 In the measurement of fire gases, it is imperative to use
5.2.4 Collection and transport of samples must be accom-
procedures that are both reliable and appropriate to the unique plished in such a way that the analyses properly reflect the
atmosphere of a given fire environment. To maximize the
nature and concentration of species in the combustion gas
reliability of test results, it is essential to establish the follow- stream. Heated sampling lines made from an inert material are
ing:
often required. Direct sampling and immediate analysis are
4.2.1 That gaseous samples are representative of the com- preferable to retention of the sample for later analysis. Filtra-
positions existing at the point of sampling,
tion of combustion gases prior to analysis may be necessary for
4.2.2 That transfer and pretreatment of samples occur with- some applications, but may be totally incorrect for other cases
out loss, or with known efficiency, and
(see 5.9).
4.2.3 That data provided by the analytical instruments are
5.3 Test Systems—Many devices of various sizes can gen-
accurate for the compositions and concentrations at the point of
erate “fire gases’’ for analysis (4, (5)). These systems include
sampling.
large-scale facilities (fire situations simulated on a 1:1 scale
4.3 This document includes a comprehensive survey that
(see Guide E 603 and Ref (6)); large laboratory-scale tests (for
will permit an individual, technically skilled and practiced in
example, Test Method E 84); laboratory-scale chambers (for
the study of analytical chemistry, to select a suitable technique
example, Test Method E 662 (7, 8)); and microcombustion
from among the alternatives. It will not provide enough
furnace or tube furnace assemblies (2, (9)).
information for the setup and use of a procedure (this infor-
5.3.1 In general, the combustion devices (test chambers) fall
mation is available in the references).
into three categories:
4.4 Data generated by the use of techniques cited in this
(1) closed chambers (for example, Test Method E 662);
document should not be used to rank materials for regulatory
(2) open chambers (for example, a full-scale room burn);
purposes.
(3) flow-through systems (for example, Test Method E 84).
5.3.2 Different test chamber sizes and configurations require
5. Sampling
different methods of sampling and analysis. Appropriate ana-
5.1 More errors in analysis result from poor and incorrect
lytical procedures and equipment must be selected. In a
sampling than from any other part of the measurement process
full-scale fire experiment the sampling frequency and detection
(1, 2). It is therefore essential to devote special attention to
level and accuracy may not need to be the same as in a small
sampling, sample transfer, and pretreatment aspects of the
laboratory-scale experiment.
analysis procedures.
5.4 Reactivity of Fire Gases:
5.2 Planning for Analysis—Definitive answers should be
5.4.1 Fire gases to be analyzed range from relatively inert
sought and provided to the following questions during the
and volatile substances, such as carbon monoxide (CO) and
planning stage: (1) Why is the sampling (analysis) being
carbon dioxide (CO ), to reactive acid gases such as hydrogen
performed? (2) What needs to be measured? (3) Where will
fluoride (HF), HCl, and hydrogen bromide (HBr). Other
samples be taken? (4) When does one sample? (5) How are
species frequently determined are oxygen, the sulfur-oxide
samples collected? (3).
species sulfur dioxide (SO ) and sulfur trioxide (SO ); the
2 3
5.2.1 All aspects of sampling and analysis relate to the
nitrogen-containing species hydrogen cyanide (HCN), nitric
fundamental reasons for performing the analysis. Analysis of
oxide (NO), and nitrogen dioxide (NO ); and hydrocarbons
combustion products is normally performed for one of the
and partially oxidized hydrocarbons.
following reasons: for research on the composition of the
5.4.2 The following potential problems must be avoided or
gases; to relate directly to flammability, smoke generation,
minimized by proper design of the sampling system and choice
toxic or irritant effects; to study mechanisms of combustion; or
of materials of construction:
for development of test equipment. The experimenter should
(1) Reaction of the gaseous products with materials used in
decide exactly what type of information the analysis must
sampling lines and test equipment that could lead to loss of
provide. The necessary detection limits, acceptable errors, and
sample and potential equipment failure;
possible or tolerable interferences must be determined.
(2) Adsorption, absorption, or condensation of gaseous
5.2.2 A representative sample must be obtained; however,
products in the sampling system or on particles trapped in the
sampling must not interfere with the test (for example, sam-
filtration system;
pling could alter the atmosphere in an animal toxicity experi-
(3) Reaction among species present in the gaseous sample;
ment or in a smoke measurement device). The size and shape
(4) Interferences caused by species in the sample, other than
of the test chamber affects the possible location and number of
the product being analyzed, that respond to the analytical
sampling probes.
method.
5.2.3 Single or cumulative samples may be adequate for
5.5 Sampling Frequency—The frequency of sampling is
many requirements; however, a continuous monitor may be
based primarily on the information sought. Most requirements
desirable for the determination of concentration-time depen-
will be met by one of the following three sampling modes:
(1) The quantity formed during the experiment is determined
5 by collecting one time-integrated sample (2);
The boldface numbers in parentheses refer to the list of references appended to
this standard. (2) The concentration is determined at a limited number of
E 800
time points during the experiment (10); inside the chamber. The sample streams were then combined
before being introduced into the analyzers. Previous experi-
(3) The concentration is determined either continuously or
ments had demonstrated that significant stratification occurred
with sufficient frequency to represent it as a function of time (6,
in the chamber during part of the test. In a full-scale bedroom
8, 10, 11).
fire test (6), four gas sampling probes were used.
5.5.1 The two techniques used most commonly in the past
5.6.2 Guidelines developed for the monitoring of the emis-
have been the single, integrated sample and sampling at fixed
sion of pollutants (1, 17, 18) can be utilized for the demon-
time intervals. However, techniques for continuous analysis of
stration of the mass flow rates of combustion products through
certain species are now readily available (CO, CO , and
ducts. Traverses across the ducts (in a steady-state experiment)
oxygen (O )); while continuous analysis of other compounds
with a CO- or CO -probe can be useful for determining
of interest have been reported (12). 2
whether a need exists for multiple sampling sites.
5.5.2 The integrated sampling technique entails collection
5.7 Sampling Probes:
of all the products (or a continuous sample from the gas
5.7.1 Sampling probes must withstand exposure to the test
stream) into an unreactive sampling bag such as polytetrafluo-
environment and must not affect the integrity of the sample
roethylene (PTFE) or absorption of the species of interest in an
with respect to the substances being analyzed. Care should be
appropriate solvent in an impinger for the duration of the
exercised in heating probes of PTFE; temperatures above
experiment. Analyses are then performed on the contents of the
250°C may affect their physical properties.
bag or trapping medium (9). Water-soluble species such as HCl
5.7.2 Probes fabricated from PTFE, PTFE-lined stainless-
or HBr have been collected in solution impingers over the
steel, glass-lined stainless-steel, unlined stainless-steel, boro-
duration of the experiment, enabling analysis of the “inte-
silicate glass, or quartz tubing are frequently used for sample
grated” sample. The gas flow rate through the impinger and the
extraction from combustion or pyrolysis systems. Stainless
liquid volume determine the buildup of acid gas in the solution
steel should not be used with combustion products containing
(the solubility of the species at the given gas flow rate should
hydrogen halides since it reacts with these compounds. Glass
be verified). The integrated sampling techniques provide either
and quartz react with fluorides; the latter substance can be
the “average” concentration of the particular species over the
extracted with PTFE probes if the atmospheric temperature is
duration of the test or, for certain flow-through test procedures,
low enough. If the temperature is high, an alternative sampling
a measure of the total amount of that species produced in the
technique would be placing absorption tubes at the sampling
experiment. In this latter case, a total gas flow measurement is
point, housing the tubes in an ice-water bath, and trapping HF
required.
upstream of all sampling lines and pumps (13, 14).
5.5.3 Continuous or frequent, periodic sampling is often
5.7.3 Probe and transfer lines should be heated to prevent
desirable. This limits further reaction of reactive species (such
losses of some combustion products such as total hydrocarbons
as HCl, HBr, and HCN), and is useful for studies of time-
due to condensation and HBr, HCl, nitrogen oxide (NO ), and
x
dependent, cumulative effects of toxic gases (such as CO) on
SO due to s
...

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