ASTM D3249-95(2019)
(Practice)Standard Practice for General Ambient Air Analyzer Procedures
Standard Practice for General Ambient Air Analyzer Procedures
SIGNIFICANCE AND USE
5.1 The significance of this practice is adequately covered in Section 1.
SCOPE
1.1 This practice is a general guide for ambient air analyzers used in determining air quality.
1.2 The actual method, or analyzer chosen, depends on the ultimate aim of the user: whether it is for regulatory compliance, process monitoring, or to alert the user of adverse trends. If the method or analyzer is to be used for federal or local compliance, it is recommended that the method published or referenced in the regulations be used in conjunction with this and other ASTM methods.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 6.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: D3249 − 95 (Reapproved 2019)
Standard Practice for
General Ambient Air Analyzer Procedures
This standard is issued under the fixed designation D3249; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript 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 D3609Practice for Calibration Techniques Using Perme-
ation Tubes
1.1 Thispracticeisageneralguideforambientairanalyzers
D3670Guide for Determination of Precision and Bias of
used in determining air quality.
Methods of Committee D22
1.2 The actual method, or analyzer chosen, depends on the
E177Practice for Use of the Terms Precision and Bias in
ultimate aim of the user: whether it is for regulatory
ASTM Test Methods
compliance, process monitoring, or to alert the user of adverse
E200Practice for Preparation, Standardization, and Storage
trends. If the method or analyzer is to be used for federal or
of Standard and Reagent Solutions for ChemicalAnalysis
localcompliance,itisrecommendedthatthemethodpublished
orreferencedintheregulationsbeusedinconjunctionwiththis
3. Terminology
and other ASTM methods.
3.1 Definitions—For definitions of terms used in this prac-
1.3 The values stated in SI units are to be regarded as
tice other than those following, refer to Terminology D1356.
standard. No other units of measurement are included in this
3.1.1 analyzer, n—the instrumental equipment necessary to
standard.
perform automatic analysis of ambient air through the use of
1.4 This standard does not purport to address all of the
physical and chemical properties and giving either cyclic or
safety concerns, if any, associated with its use. It is the
continuous output signal.
responsibility of the user of this standard to establish appro-
3.1.1.1 analyzer system, n—all sampling, analyzing, and
priate safety, health, and environmental practices and deter-
readoutinstrumentationrequiredtoperformambientairquality
mine the applicability of regulatory limitations prior to use.
analysis automatically.
For specific hazard statements, see Section 6.
3.1.1.2 sample system, n—equipment necessary to provide
1.5 This international standard was developed in accor-
the analyzer with a continuous representative sample.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
3.1.1.3 readout instrumentation, n—outputmeters,recorder,
Development of International Standards, Guides and Recom-
or data acquisition system for monitoring analytical results.
mendations issued by the World Trade Organization Technical
3.1.2 full scale, n—the maximum measuring limit for a
Barriers to Trade (TBT) Committee.
given range of an analyzer.
2. Referenced Documents
3.1.3 interference, n—an undesired output caused by a
substance or substances other than the one being measured.
2.1 ASTM Standards:
The effect of interfering substance(s), on the measurement of
D1356Terminology Relating to Sampling and Analysis of
interest, shall be expressed as: (6) percentage change of
Atmospheres
measurement compared with the molar amount of the interfer-
D1357Practice for Planning the Sampling of the Ambient
ent. If the interference is nonlinear, an algebraic expression
Atmosphere
should be developed (or curve plotted) to show this varying
effect.
ThispracticeisunderthejurisdictionofASTMCommitteeD22onAirQuality
3.1.4 lag time, n—thetimeintervalfromastepchangeinthe
and is the direct responsibility of Subcommittee D22.03 on Ambient Atmospheres
and Source Emissions.
inputconcentrationattheanalyzerinlettothefirstcorrespond-
Current edition approved Oct. 1, 2019. Published October 2019. Originally
ing change in analyzer signal readout.
approved in 1973. Last previous edition approved in 2011 as D3249–95 (2011).
DOI: 10.1520/D3249-95R19.
3.1.5 linearity, n—the maximum deviation between an ac-
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
tual analyzer reading and the reading predicted by a straight
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
line drawn between upper and lower calibration points. This
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. deviation is expressed as a percentage of full scale.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D3249 − 95 (2019)
3.1.6 minimum detection limit, n—the smallest input con- information, calibration techniques, methods for validating
centration that can be determined as the concentration ap- results, and general comments related to ambient air analyzer
proaches zero. methodsofanalysis.Thisisintendedtobeacommonreference
method which can be applied to all automatic analyzers in this
3.1.7 noise, n—random deviations from a mean output not
category.
caused by sample concentration changes.
3.1.8 operating humidity range of analyzer, n—the range of
5. Significance and Use
ambientrelativehumidityofairsurroundingtheanalyzer,over
5.1 Thesignificanceofthispracticeisadequatelycoveredin
which the analyzer will meet all performance specifications.
Section 1.
3.1.8.1 operating humidity range of sample, n—therangeof
ambient relative humidity of air which passes through the 6. Hazards
analyzer’s sensing system, over which the monitor will meet
6.1 Each analyzer installation should be given a thorough
all performance specifications. 3
safety engineering study.
3.1.9 operational period, n—the period of time over which
6.2 Electricallytheanalyzersystemaswellastheindividual
the analyzer can be expected to operate unattended within
components shall meet all code requirements for the particular
specifications.
area classification.
3.1.10 operating temperature range of analyzer, n—the
6.2.1 Allanalyzersusing120-V,a-c,60-Hz,3-wiresystems
range of ambient temperatures of air surrounding the analyzer,
should observe proper polarity and should not use mechanical
over which the monitor will meet all performance specifica-
adapters for 2-wire outlets.
tions.
6.2.2 The neutral side of the power supply at the analyzer
3.1.10.1 operating temperature range of sample, n—the
should be checked to see that it is at ground potential.
rangeofambienttemperaturesofair,whichpassesthroughthe
6.2.3 The analyzer’s ground connection should be checked
analyzer’s sensing system, over which the analyzer will meet
to earth ground for proper continuity.
all performance specifications.
6.2.4 Any analyzer containing electrically heated sections
should have a temperature-limit device.
3.1.11 output, n—asignalthatisrelatedtothemeasurement,
6.2.5 Theanalyzer,andanyrelatedelectricalequipment(the
and intended for connection to a readout or data acquisition
system), should have a power cut-off switch, and a fuse or
device. Usually this is an electrical signal expressed as milli-
breaker, on the “hot” side of the line(s) of each device.
volts or milliamperes full scale at a given impedance.
3.1.12 precision, n—see Guide D3670.
6.3 Full consideration must be given to safe disposal of the
analyzer’s spent samples and reagents.
3.1.12.1 repeatability, n—a measure of the precision of the
analyzer to repeat its results on independent introductions of
6.4 Pressurereliefvalves,ifapplicable,shallbeprovidedto
the same sample at different time intervals. This is that
protect both the analyzer and analyzer system.
differencebetweentwosuchsingleinstrumentresults,obtained
6.5 Precautions should be taken when using cylinders con-
during a stated time interval, that would be exceeded in the
taining gases or liquids under pressure. Helpful guidance may
long run in only one case in twenty when the analyzer is
be obtained from Refs (1-5).
operating normally.
6.5.1 Gascylindersmustbefastenedtoarigidstructureand
3.1.12.2 reproducibility, n—a measure of the precision of
not exposed to direct sun light or heat.
different analyzers to repeat results on the same sample.
6.5.2 Specialsafetyprecautionsshouldbetakenwhenusing
3.1.13 range, n—theconcentrationregionbetweenthemini-
or storing combustible or toxic gases to ensure that the system
mum and maximum measurable limits.
is safe and free from leaks.
3.1.14 response time, n—the time interval from a step
7. Installation of Analyzer System
change in the input concentration at the analyzer inlet to an
output reading of 90% of the ultimate reading. 7.1 Assure that information required for installation and
operation of the analyzer system is supplied by the manufac-
3.1.15 rise time, n—response time minus lag time.
turer.
3.1.16 span drift, n—the change in analyzer output over a
7.2 Study operational data and design parameters furnished
stated time period, usually 24 h of unadjusted continuous
by the supplier before installation.
operation, when the input concentration is at a constant, stated
upscale value. Span drift is usually expressed as a percentage
change of full scale over a 24-h operational period.
Theuser,equipmentsupplier,andinstallershouldbefamiliarwithrequirements
of the National Electrical Code, any local applicable electrical code, U.L. Safety
3.1.17 zero drift, n—the change in analyzer output over a
Codes, and the Occupational Safety & Health Standards (Federal Register, Vol 36,
statedtimeperiodofunadjustedcontinuousoperationwhenthe
No. 105, Part II, May 29, 1971). Helpful guidance may also be obtained fromAPI
input concentration is zero; usually expressed as a percentage
RP500,“ClassificationofAreasforElectricalInstallationsinPetroleumRefineries;”
ISA RP12.1, “Electrical Instruments in Hazardous Atmospheres;” ISA RP12.2,
change of full scale over a 24-h operational period.
“Intrinsically Safe and Nonincendive Electrical Instruments;” ISARP12.4, “Instru-
ment Purging for Reduction of Hazardous Area Classification;” and AP RP550,
4. Summary of Practice
“Installation of Refinery Instruments and Control Systems, Part II.”
4.1 Aprocedure for ambient air analyzer practices has been
The boldface numbers in parentheses refer to a list of references at the end of
outlined. It presents definitions and terms, sampling this standard.
D3249 − 95 (2019)
7.3 Review all sample requirements with the equipment 8.2.2 Formostapplications,aminimumofninesamplesare
supplier. The supplier must completely understand the appli- required, and these shall be withdrawn each cycle for intermit-
cation and work closely with the user and installer. It is tent analyzers or for continuous analyzers after a stable
absolutely necessary to define carefully all conditions of response is achieved.
intended operation, components in the atmosphere to be
8.2.3 Aftereachspotsamplehasbeenremoved,recorditas
analyzed, and expected variations in sample composition. to time, sample number, date and corresponding analyzer
readout.Thisequivalentreadoutisusedinestablishingasingle
7.4 Choose materials of construction in contact with the
calibration point.
ambient air sample to be analyzed to prevent reaction of
8.2.4 Each spot sample must be analyzed in duplicate using
materials with the sample, sorption of components from the
the corresponding ASTM test method and the two results
sample, and entrance of contaminants through infusion or
averaged. The standard deviation for the spot sample is
diffusion (6-9).
calculated as the difference (larger value minus the smaller
7.4.1 Choose materials of construction and components of
=
value) divided by 2. If this standard deviation exceeds the
theanalyzersystemtowithstandtheenvironmentinwhichitis
test method repeatability limit, r, (see Practice E177) then that
installed.
test average must be discarded. (This assumes that a repeat-
7.4.2 Avoid the use of pipe-thread compounds in favor of
ability limit has been determined for the test method and the
polytetrafluorethylene tape.
laboratory conducting the test. This rejection criterion will
7.5 Select the sampling point so as to provide a representa-
discard 5% of the spot sample results even if the test method
tive and measurable sample as close as possible to the sample
is operating properly.)
system and analyzer (see Practice D1357).
8.2.5 Determine the amount of calibration offset by averag-
7.5.1 Provide a convenient access to the entire analyzer
ing the deviations, as shown in Table 1, and correct the
system.
analyzerreadoutaccordingly.Itmaybenecessarytoreviewthe
7.5.2 Provide a necessary connection for introducing stan-
manufacturer’s recommended procedure for making calibra-
dard samples or withdrawing laboratory check samples imme-
tion offset adjustments.
diately upstream of the analyzer sampling system.
8.3 Standard Sample Calibration Method—Use a standard
7.6 Sample lines should be as short as practical.
7.6.1 Install the analyzer’s exhaust so that no liquid or gas reference sample in accordance with the ASTM test method
chosen, or by generating a known sample concentration, using
pressure buildup will occur. Provide proper venting, as far as
possible from the sampling point. NIST calibrated permeation tubes (see Practice D3609).
8.3.1 A standard sample benchmark analysis is made by
7.7 After the installation has been completed, allow the
averaging the results of at least nine determinations using the
analyzer to stabilize before testing performance specifications.
corresponding ASTM test method. This average value is
acceptable for benchmark analysis only if the corresponding
8. Calibration
standarddeviationislowerinmagnitudethanthetestmethod’s
8.1 Oneofthemostimportantstepsinanalyzeroperationis
repeatability limit, r, (see Practice E177).
proper calibration of the instrument. Various calibration tech-
8.3.2 Check all operating parameters of the system in
niques may be used depending on the sample’s physical or
accordance with the instrument specifications and data for
chemical property requiring measurement. Frequency of cali-
specificanalysis.Allowsufficienttimefortheanalyzertoreach
bration depends largely on the application, degree of accuracy,
equilibrium as indicated by a stable output.
and reliability expected. Perform calibration using spot
8.3.3 Introduce the standard reference sample into the
samples (ambient) or a standard reference sample and utilize
analyzer using the recommended instrument operational pro-
theanalyzeradjustmentsasrecommendedbythemanufacturer.
cedure. Activate the readout equipme
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