ASTM D4298-95(1999)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D4298–95 (Reapproved 1999)
Standard Guide for
Intercomparing Permeation Tubes to Establish Traceability
This standard is issued under the fixed designation D 4298; 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.
1. Scope E 617 Specification for Laboratory Weights and Precision
Mass Standards
1.1 This guide covers two procedures for establishing the
permeation rate of a permeation tube and defining the uncer-
3. Terminology
tainty of the rate by comparison to National Institute of
3.1 Definitions:
Standards and Technology’s Standard Reference Materials
3.1.1 For definitions of terms used in this guide, refer to
(SRM).
Terminology D 1356.
1.2 Procedure A consists of a direct comparison of the
3.1.2 Definitions of Terms Specific to This Standard:
permeation rate of the device undergoing calibration with that
3.1.2.1 working standard—a standard used in the laboratory
of an SRM.
or field for periodic standardization of a measuring instrument.
1.3 Procedure B consists of a gravimetric calibration pro-
cess in which a certified permeation tube is used as a quality
4. Summary of Guide
control for the measurements.
4.1 Procedure A—A certified SRM permeation source, ob-
1.4 Both procedures are limited to the case where a suitable
tained from the National Institute of Standards andTechnology
certified permeation device is available.
is used to calibrate a continuous analyzer. The analyzer is then
1.5 This standard does not purport to address all of the
used to measure the concentration of a gaseous mixture
safety concerns, if any, associated with its use. It is the
generated from the permeation tube under calibration. Equa-
responsibility of the user of this standard to establish appro-
tionsareprovidedthatpermitcalibrationofthepermeationrate
priate safety and health practices and determine the applica-
of the latter from the test data.
bility of regulatory limitations prior to use. (See 8.2 on Safety
4.2 Procedure B—The permeation source is calibrated,
Precautions.)
gravimetrically, using temperature and mass standards trace-
2. Referenced Documents able to NIST standards. The validity of the calibration is
confirmed by concurrently measuring the permeation rate of a
2.1 ASTM Standards:
certified NIST SRM.
D 1356 Terminology Relating to Sampling and Analysis of
Atmospheres
5. Significance and Use
D 3249 Practice for General Ambient Air Analyzer Proce-
2 5.1 The accuracy of air pollution measurements is directly
dures
dependent upon accurate calibrations.
D 3609 Practice for Calibration Techniques Using Perme-
2 5.2 Such measurements gain accuracy and can be intercom-
ation Tubes
pared when the measurement procedures are traceable to
D 3631 Test Methods for Measuring Surface Atmospheric
2 national measurement standards.
Pressure
5.3 This guide describes procedures for enhancing the
E 1 Specification for ASTM Thermometers
accuracyofairpollutionmeasurementswhichmaybespecified
E 319 Practice for the Evaluation of Single-Pan Mechanical
4 by those organizations requiring traceability to national stan-
Balances
dards.
6. Apparatus
ThisguideisunderthejurisdictionofASTMCommitteeD-22onSamplingand
Analysis of Atmospheres and is the direct responsibility of Subcommittee D22.01
6.1 For apparatus used in the calibration of permeation
on Quality Control.
devices, refer to Practice D 3609.
Current edition approved Jan. 15, 1995. Published March 1995. Originally
e1
6.1.1 The thermometers used shall conform to Specification
published as D 4298 – 83. Last previous edition D 4298 – 83 (1993) .
Annual Book of ASTM Standards, Vol 11.03. E 1andshallhavecalibrationcertificatestraceabletotheNIST.
Annual Book of ASTM Standards, Vol 14.03.
Measurement uncertainty should be 0.1°C or less.
Annual Book of ASTM Standards, Vol 14.02.
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D4298
6.1.2 ThemercurybarometershallconformtoTestMethods 9.1.2 Optimize the performance of the analytical instrument
D 3631. according to the manufacturer’s instructions.
6.2 Apparatus for Procedure A: 9.1.3 Using dry air or nitrogen, set the zero point of the
6.2.1 Analytical Instruments—An analytical instrument re- instrument.
sponsive to the permeant with the following minimum perfor- 9.1.4 Use the gas generation system to provide gas concen-
mance specifications: trations corresponding to 20, 40, 60, and 80 % of full-scale
readings. Record the concentration and respective readings.
Noise 1 % of full-scale
Zero drift 64 % of full-scale per day
Repeat the measurements in random order.
Span drift 63 % of full-scale
9.1.5 Plot concentration versus instrument readings and
Range 0 to 0.5 ppm (or appropriate for source strength)
draw the line of best fit, or alternatively fit by linear least
6.2.2 Continuous strip chart recorder with the following
squares regression. Calculate the slope and express as ppm/
minimum performance specifications:
scale reading.
Accuracy 60.25 % full-scale deflection
9.1.5.1 If any point deviates by more than 61 % from the
Chart width no less than 6 in.
line of best fit, repeat the calibration.
Time for full-scale travel 1 s
9.2 Procedure B:
6.3 Apparatus for Procedure B:
9.2.1 The standard masses and the thermometer used must
6.3.1 Analytical balance, meeting the requirements of Prac-
have a valid calibration certificate or be calibrated prior to use.
tices E 319 and D 3609.
6.3.2 Analytical weights meeting the requirements of Speci-
10. Procedure
fication E 617 and having a calibration certificate traceable to
10.1 Procedure A:
the NIST.
10.1.1 Place test permeation device in the system, equili-
brate at the temperature of calibration, and generate gas
7. Materials
mixtures corres
...