Standard Test Method for Beta Particle Radioactivity of Water

SIGNIFICANCE AND USE
5.1 This test method was developed for the purpose of measuring the gross beta radioactivity in water. It is used for the analysis of both process and environmental water to determine gross beta activity.
SCOPE
1.1 This test method covers the measurement of beta particle activity of water. It is applicable to beta emitters having maximum energies above 0.1 MeV and at activity levels above 0.02 Bq/mL (540 pCi/L) of radioactive homogeneous water for most counting systems. This test method is not applicable to samples containing radionuclides that are volatile under conditions of the analysis.  
1.2 This test method can be used for either absolute or relative determinations. In tracer work, the results may be expressed by comparison with a standard which is defined to be 100 %. For radioassay, data may be expressed in terms of a known radionuclide standard if the radionuclides of concern are known and no fractionation occurred during processing, or may be expressed arbitrarily in terms of some other standard such as 137Cs. General information on radioactivity and measurement of radiation may be found in the literature2, 3, 4, 5 and Practices D3648.  
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.  
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.

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Published
Publication Date
14-Dec-2017
Technical Committee
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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: D1890 − 15 (Reapproved 2017)
Standard Test Method for
Beta Particle Radioactivity of Water
This standard is issued under the fixed designation D1890; 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 Development of International Standards, Guides and Recom-
mendations issued by the World Trade Organization Technical
1.1 This test method covers the measurement of beta par-
Barriers to Trade (TBT) Committee.
ticle activity of water. It is applicable to beta emitters having
maximumenergiesabove0.1MeVandatactivitylevelsabove
2. Referenced Documents
0.02Bq/mL(540pCi/L)ofradioactivehomogeneouswaterfor
most counting systems. This test method is not applicable to
2.1 ASTM Standards:
samples containing radionuclides that are volatile under con-
D1129Terminology Relating to Water
ditions of the analysis.
D1193Specification for Reagent Water
D2777Practice for Determination of Precision and Bias of
1.2 This test method can be used for either absolute or
Applicable Test Methods of Committee D19 on Water
relative determinations. In tracer work, the results may be
D3370Practices for Sampling Water from Closed Conduits
expressedbycomparisonwithastandardwhichisdefinedtobe
D3648Practices for the Measurement of Radioactivity
100%. For radioassay, data may be expressed in terms of a
known radionuclide standard if the radionuclides of concern
3. Terminology
are known and no fractionation occurred during processing, or
may be expressed arbitrarily in terms of some other standard
3.1 Definitions:
such as Cs. General information on radioactivity and mea-
3.1.1 For terms not defined in this standard or in Terminol-
2, 3, 4, 5
surementofradiationmaybefoundintheliterature and
ogy D1129, reference may be made to other published glossa-
Practices D3648.
ries.
1.3 The values stated in SI units are to be regarded as
3.2 Definitions of Terms Specific to This Standard:
standard. No other units of measurement are included in this
3.2.1 becquerel, n—a unit of radioactivity equivalent to 1
standard.
nuclear transformation per second.
1.4 This standard does not purport to address all of the
3.2.2 betaenergy,maximum,n—themaximumenergyofthe
safety concerns, if any, associated with its use. It is the
beta-particle energy spectrum produced during beta decay of a
responsibility of the user of this standard to establish appro-
given radioactive species.
priate safety, health, and environmental practices and deter-
3.2.2.1 Discussion—Sinceagivenbeta-particleemittermay
mine the applicability of regulatory limitations prior to use.
decay to several different quantum states of the product
1.5 This international standard was developed in accor-
nucleus, more than one maximum energy may be listed for a
dance with internationally recognized principles on standard-
given radioactive species.
ization established in the Decision on Principles for the
3.2.3 counter background, n—in the measurement of
radioactivity, the counting rate resulting from factors other
This test method is under the jurisdiction ofASTM Committee D19 on Water
than the radioactivity of the sample and reagents used.
andisthedirectresponsibilityofSubcommitteeD19.04onMethodsofRadiochemi-
3.2.3.1 Discussion—Counter background varies with the
cal Analysis.
Current edition approved Dec. 15, 2017. Published December 2017. Originally
location, shielding of the detector, and the electronics; it
approved in 1961. Last previous edition approved in 2015 as D1890–15. DOI:
includes cosmic rays, contaminating radioactivity and electri-
10.1520/D1890-15R17.
cal noise.
Friedlander, G., et al., Nuclear and Radiochemistry, 3rd Ed., John Wiley and
Sons, Inc., New York, NY, 1981.
Price, W. J., Nuclear Radiation Detection, 2nd Ed., McGraw-Hill Book Co.,
Inc., New York, NY, 1964.
4 6
Lapp, R. E., and Andrews, H. L., Nuclear Radiation Physics, 4th Ed., For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Prentice-Hall Inc., New York, NY, 1972. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Overman, R. T., and Clark, H. M., Radioisotope Techniques, McGraw-Hill Standards volume information, refer to the standard’s Document Summary page on
Book Co., Inc., New York, NY, 1960. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D1890 − 15 (2017)
3.2.4 counter beta-particle effıciency, n—in the measure- Thus, for reliable relative measurements, hold all variables
ment of radioactivity, that fraction of beta particles emitted by constant while counting all test samples and standards. For
a source which is detected by the counter. absolute measurements, appropriate correction factors are ap-
plied. The effects of geometry, backscatter radiation, source
3.2.5 counter effıciency, n—in the measurement of
diameter, self-scatter and self-absorption, absorption in air and
radioactivity, that fraction of the disintegrations occurring in a
detector window for external counters, and counting coinci-
source which is detected by the counter.
2, 3, 4, 5
dencelosseshavebeendiscussed andmaybedescribed
3.2.6 radioactive homogeneous water, n—water in which
by the following relation:
the radioactive material is uniformly dispersed throughout the
cps 5 Bq ~G !~f !~f !~f !~f !~f ! (1)
volume of water sample and remains so until the measurement b p bs aw d ssa c
is completed or until the sample is evaporated or precipitating
where:
reagents are added to the sample.
cps = recordedcountspersecondcorrectedforbackground,
3.2.7 reagent background, n—in the measurement of radio-
Bq = disintegrations per second yielding beta particles,
b
activity of water samples, the counting rate observed when a
G = point source geometry (defined by the solid angle
p
sample is replaced by mock sample salts or by reagent
subtended by the sensitive area of the detector),
chemicals used for chemical separations that contain no f = backscatter factor or ratio of cps with backing to cps
bs
analyte. without backing,
f = factortocorrectforlossesduetoabsorptionintheair
3.2.7.1 Discussion—Reagent background varies with the
aw
reagent chemicals and analytical methods used and may vary and window of external detectors. It is equal to the
ratio of the actual counting rate to that which would
with reagents from different manufacturers and from different
processing lots. beobtainediftherewerenoabsorptionbytheairand
window between the source and sensitive volume of
4. Summary of Test Method the detector. Expressed in terms of absorption coef-
−µx
ficient and density of absorber, f =e , where
aw
4.1 Beta radioactivity may be measured by one of several
µ=absorption coefficient, in square centimetres per
types of instruments composed of a detecting device and
milligram, and x=absorber density in milligrams per
combined amplifier, power supply, and scaler—the most
square centimetre.
widely used being proportional or Geiger-Müller counters.
f = factor to correct a spread source counting rate to the
d
Where a wide range of counting rates is encountered (0.1 to
countingrateofthesameactivityasapointsourceon
1300 counts per seconds), the proportional-type counter is
the same axis of the system,
preferable due to a shorter resolving time and greater stability
f = factor to correct for the absorption and scatter of beta
ssa
of the instrument. The test sample is reduced to the minimum
particles within the material accompanying the radio-
weight of solid material having measurable beta activity by
active element, and
precipitation, ion exchange resin, or evaporation techniques.
f = factor for coincident events to correct the counting
c
Beta particles entering the sensitive region of the detector
rate for instrument resolving time losses and defined
produceionizationofthecountinggas.Thenegativeionofthe
by the simplified equation, f =1−nr, where, n=the
c
original ion pair is accelerated towards the anode, producing
observed counts per second, and r=instrument re-
additional ionization of the counting gas and developing a
solvingtimeinseconds.Generally,thesamplesizeor
voltage pulse at the anode. By use of suitable electronic
source to detector distance is varied to obtain a
apparatus, the pulse is amplified to a voltage sufficient for
counting rate that precludes coincident losses. Infor-
operation of the counter scaler. The number of pulses per unit
mation on the effect of random disintegration and
of time is related to the disintegration rate of the test sample.
instrument resolving time on the sample count rate as
Thebeta-particleefficiencyofthesystemcanbedeterminedby
wellasmethodsfordeterminingtheresolvingtimeof
use of prepared standards having the same radionuclide com-
the counting system may be found in the literature.
position as the test specimen and equivalent residual plated
For most applications, a detector system is calibrated using
solids.An arbitrary efficiency factor can be defined in terms of
a single beta emitting radionuclide and an efficiency of
some other standard such as cesium-137.
detection, f , response curve generated for various sample
o
residue weights. The efficiency of detection for each sample
5. Significance and Use
residualweightincorporatesallthefactorsmentionedaboveso
5.1 This test method was developed for the purpose of
that:
measuring the gross beta radioactivity in water. It is used for
f 5 cps/Bq 5 ~G !~f !~f !~f !~f !~f ! (2)
o p bs aw d ssa c
the analysis of both process and environmental water to
determine gross beta activity.
6.1.1 In tracer studies or tests requiring only relative mea-
surements in which the data are expressed as being equivalent
6. Measurement Variables
to a defined standard, the above correction factors can be
6.1 The relatively high absorption of beta particles in the simply combined into a counting efficiency factor. The use of
sample media and any material interposed between source and a counting efficiency factor requires that sample mounting,
sensitive volume of the counter results in an interplay of many density of mounting dish, weight of residue in milligrams per
variables which affect the counting rate of the measurement. squarecentimetre,andradionuclidecomposition,inadditionto
D1890 − 15 (2017)
conditions affecting the above described factors, remain con- with a sample holder containing slots for positioning the
stant throughout the duration of the test and that the compara- sample at three or four distances from the detector window,
tive standard be prepared for counting in the same manner as varying from approximately 5 to 100 mm from tube flange.
the test samples. The data from comparative studies between
8.1.2 DetectorShield—Thedetectorassemblyissurrounded
independentlaboratories,whennotexpressedinabsoluteunits,
by an external radiation shield of massive metal equivalent to
are more meaningful when expressed as percentage relation-
approximately 51 mm of lead and lined with 3.2-mm thick
shipsorastheequivalentofadefinedstandard.Expressingthe
aluminum. The material of construction should be free from
data in either of these two ways minimizes the differences in
detectable radioactivity. The shield has a door or port for
counters and other equipment and in techniques used by the
inserting or removing specimens. Detectors having other than
laboratories conducting the tests.
completely opaque windows are light sensitive. The design of
the shield and its openings shall eliminate direct light paths to
6.2 The limit of sensitivity for both Geiger-Müller and
thedetectorwindow;bevelingofdoorandopeningisgenerally
proportional counters is a function of the background counting
satisfactory.Thepercentageofthebetaparticlesscatteredfrom
rate. Massive shielding or anti-coincidence detectors and
the walls of the shield into the detector can be reduced by
circuitry, or both, are generally used to reduce the background
increasing the internal diameter of the shield. The use of a
counting rate to increase the sensitivity.
detector without a shield will significantly increase the back-
7. Interferences ground and the detection capability.
8.1.3 Scaler—Normally the scaler, mechanical register,
7.1 Material interposed between the test sample and the
power supply, and amplifier are contained in a single chassis,
instrumentdetector,aswellasincreasingdensityinthesample
generally termed the scaler. The power supply and amplifier
containing the beta emitter, produces significant losses in
sections are matched by the manufacturer with the type of
sample counting rates. Liquid samples are evaporated to
detectortoproducesatisfactoryoperatingcharacteristicsandto
dryness in dishes that allow the sample to be counted directly
provide sufficient range in adjustments to maintain controlled
by the detector. Since the absorption of beta particles in the
conditions. The manufacturer shall provide resolving time
sample solids increases with increasing density and varies
information for the counting system. The scaler shall have
inversely with the maximum beta energy, plated solids shall
capacity for storing and visually displaying at least 10 counts
remain constant between related test samples and should
and with a resolving time no greater than 250 µs for use with
duplicate the density of the solids of the plated standard.
Geiger-Müller detectors or 5 µs for use with proportional
7.2 Most beta radiation counters are sensitive to alpha,
detectors. The instrument shall have an adjustable input sensi-
gamma, and X-ray radiations, with the degree of efficiency
tivity matched and set by the manufacturer to that of the
2, 3, 4, 5
dependent upon the type of detector. The effect of
detector, and a variable high-voltage power supply with indi-
interfering radiations on the beta counting rate is more easily
cating meter.
evaluated with external-type counters where appropriate ab-
sorbers can be used to evaluate the effects of interfering 8.2 Sample Mounting—Sample mounting shall utilize
dishes having a flat bottom of a diameter no greater than that
radiation.
of the detector window preferably having 3.2-mm high side
8. Apparatus
walls with the angle between dish bottom and side equal to or
greater than 120° to reduce side-wall scattering (Note 1).
8.1 Beta Partic
...

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