ASTM D7902-14
(Terminology)Standard Terminology for Radiochemical Analyses
Standard Terminology for Radiochemical Analyses
SIGNIFICANCE AND USE
3.1 This terminology standard describes terms and definitions used in standards for radiochemical analysis maintained by ASTM Committee D19 on Water. The terminology is also recommended for general use in the radiochemistry community.
SCOPE
1.1 This standard describes terminology commonly used in radiochemistry and radioanalysis.
1.2 The values stated in SI units are to be regarded as standard. Other units of measurement, including some units that are not accepted for use with the SI, are also defined.
1.3 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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D7902 − 14
StandardTerminology for
Radiochemical Analyses
This standard is issued under the fixed designation D7902; 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.
1. Scope 3. Significance and Use
1.1 This standard describes terminology commonly used in 3.1 This terminology standard describes terms and defini-
radiochemistry and radioanalysis. tions used in standards for radiochemical analysis maintained
by ASTM Committee D19 on Water. The terminology is also
1.2 The values stated in SI units are to be regarded as
recommended for general use in the radiochemistry commu-
standard. Other units of measurement, including some units
nity.
that are not accepted for use with the SI, are also defined.
1.3 This standard does not purport to address all of the
4. Terminology: Terms and Definitions
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro- 4π geometry, n—geometry in which the radiation detector has
priate safety and health practices and determine the applica- essentially the same probability of detecting radiation from
bility of regulatory limitations prior to use. the source emitted in any direction.
absorption (of radiation), n—transfer of some or all of the
2. Referenced Documents
energy of a radiation to matter it traverses.
2.1 ASTM Standards:
abundance,(1) n—probabilityofemissionofagivenradiation
D7282Practice for Set-up, Calibration, and Quality Control
during the decay of an atom of a given radionuclide;
of Instruments Used for Radioactivity Measurements
radiation emission probability—also called intensity;
2.2 International Bureau of Weights and Measures Docu-
(2) see isotopic abundance.
ments:
GUMGuide to the Expression of Uncertainty in Measure- actinide, n—any element with atomic number between 89 and
103, including actinium, thorium, protactinium, uranium,
ment (GUM), 100:2008
4 neptunium, plutonium, americium, and curium.
2.3 Code of Federal Regulations Documents:
40 CFR 141.25Analytical Methods for Radioactivity
activation, n—inducement of radioactivity by irradiation.
40 CFR Appendix B to Part 136Definition and Procedure
activation analysis, n—analysis based on the characteristic
for the Determination of the Method Detection Limit
radiations emitted by nuclides formed by activation.
2.4 ANSI Documents:
−1
ANSI N42.22Traceability of Radioactive Sources to the activity (for radionuclides), A [T ], n—mean rate of radio-
National Institute of Standards active decay in a quantity of material.
DISCUSSION—Theterm activitymaybequalifiedbyspecifyingoneor
more radionuclides (for example, U activity) or the type of decay
(for example, gross alpha activity).
This terminology is under the jurisdiction ofASTM Committee D19 on Water
andisthedirectresponsibilityofSubcommitteeD19.04onMethodsofRadiochemi-
DISCUSSION—The SI unit of activity is the becquerel (Bq), which
cal Analysis.
−1
equals 1 s (one nuclear disintegration per second).
Current edition approved Jan. 15, 2014. Published January 2015. DOI: 10.1520/
D7902-14.
activity concentration, (1) n—quotient of the activity of a
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM specified quantity of material and its volume; volumic
Standards volume information, refer to the standard’s Document Summary page on
activity;
the ASTM website.
(2) n—quotient of the activity of a specified quantity of
Available from Bureau International des Poids et Mesures (BIPM), Pavillon de
material and its associated mass or size.
Breteuil F-92312 Sèvres Cedex, France, http://http://www.bipm.org.
AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments,
aliquant, n—fractional part that does not evenly divide the
732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
www.access.gpo.gov. whole.
Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
4th Floor, New York, NY 10036, http://www.ansi.org. aliquot, n—fractional part that evenly divides the whole.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D7902 − 14
DISCUSSION—Chemistscommonlyusethetermaliquottomeaneither DISCUSSION—The concept of an attenuation coeffıcient may be
an aliquant or aliquot of a sample. applied to other types of radiation provided the attenuation follows
approximately an exponential law.
alpha decay, n—radioactive decay accompanied by the emis-
attenuation curve, n—plot of attenuation factors versus an-
sion of an alpha particle.
other quantity such as distance, mass, or areic mass.
alpha particle, α particle, n—particle consisting of two
attenuation factor, n—fraction of a beam of radiation remain-
protons and two neutrons (a He nucleus) emitted from a
nucleus during certain types of radioactive decay. ing after the beam has passed through a given amount of
material.
alpha-particle spectrometry, alpha spectrometry,
n—measurementofcomponentsofasampleorsystembased Auger effect, n—ejection of an electron, called an Auger
on analysis of alpha-particle spectra. electron, from an outer shell, accompanying the filling of a
DISCUSSION—In titles and summaries, the full name alpha-particle
vacancy in an inner shell.
spectrometry is preferred. In other contexts, either name is often
DISCUSSION—The Auger effect and X-ray emission are alternative
acceptable.
means of releasing energy when such an inner shell vacancy is filled.
alpha scintillation cell, n—specially designed sealable
Auger electron, n—orbital electron ejected from an atom in
container, whose walls are coated with silver-activated zinc
the Auger effect.
sulfide (a scintillator), having a transparent window at one
end, which can be filled with a gas such as helium or
background, (1) n—in general, the normal analyte
nitrogen containing some quantity of radon and used in
concentration, radiation level, or instrument signal observed
conjunction with a scintillation counter to measure the alpha
intheabsenceoftheanalyteorintheabsenceofanyanalyte
emissions of the radon and its progeny.
contributed by a given cause;
(2) n—instrument signal observed in the absence of a
analyst, n—person who performs analyses.
source (also instrument background or detector back-
analyte, n—in an analysis, the component analyzed for.
ground).
ancestor (radionuclide), parent (radionuclide),
DISCUSSION—The unqualified term background has so many shades
n—radionuclide that produces a given nuclide in a series of
of meaning that it can be a source of confusion unless it is explained.
one or more radioactive decays.
background subtraction count, BSC, n—a source count used
DISCUSSION—The term ancestor is often used in the context of
to determine the background to be subtracted from the
indirect relationships involving a series of decays. The term parent is
often used when there is a direct relationship. sample test source count. D7282
annihilation, n—interaction between a particle and its antipar-
backscatter(ing), n—deflection of radiation by matter at any
ticle in which the original particles disappear and new angle greater than 90° from its original direction of motion.
photons or particles are produced.
backscatter peak, n—peak in a gamma-ray spectrum pro-
annihilation peak, n—peak in a gamma-ray spectrum at
duced by photons resulting from Compton scattering in the
511 keV produced by annihilations of positrons and elec-
material surrounding the detector.
trons.
baseline, n—inthegraphofaspectrum,thestraightorcurving
DISCUSSION—Each annihilation results in two 511 keV gamma-rays,
line on which peaks are superimposed.
at least one of which usually escapes from the detector without
depositing its energy.
becquerel, Bq, n—special name for the SI derived unit of
−1
anticoincidence counting, n—radiometric counting technique
activity, equal to 1 s (one nuclear disintegration per
that lowers interference levels by rejecting any event that is
second).
accompanied by one or more other events occurring within
beta decay, β decay, n—radioactive decay that results in a
a specified time interval.
−
change in atomic number but no change in mass number; β
DISCUSSION—Anticoincidence counting requires two or more
+
decay, β decay, or electron capture.
detectors, often of different types, operating simultaneously.
−
β decay, n—radioactive decay accompanied by the emission
areic, adj—in proportion to area.
−
DISCUSSION—The adjective areic, when applied to the name of a of a β particle and an antineutrino.
measurable quantity, indicates the quotient of that quantity and its
+
β decay, n—radioactive decay accompanied by the emission
associated area, as in areic activity or areic mass.
+
of a β particle and a neutrino.
attenuation (of radiation), n—decrease in intensity of radia-
− +
beta particle, β particle, n—electron (β ) or positron (β )
tion due to interactions with matter.
emitted from a nucleus during certain types of radioactive
attenuation coefficient, linear attenuation coefficient, µ or µ
l
decay.
−1
[L ], n—for a parallel beam of photons passing through a
material, the fraction of the photons removed in a short bias (voltage), n—for many types of radiation detector, a
distance, divided by that distance (see also mass attenua- voltage applied to the detector to enable it to detect an
tion coefficient). ionizing event.
D7902 − 14
blank, (1) adj—containing little or no analyte; analyte-free; a specified time interval; for example, coincidence counting
(2) see blank sample. of the beta particle and 364.5 keV gamma-ray from the
decay of I.
blank sample, n—any of various types of real or artificial
DISCUSSION—Coincidence counting requires two or more detectors,
samplesthatareexpectedtocontainlittleornoanalyte,such
often of different types, operating simultaneously.
as a method blank or reagent blank.
combined standard uncertainty, u , n—standard uncertainty
c
DISCUSSION—Use of the term blank sample without qualification or
of a measurement result obtained by uncertainty propaga-
explanation may cause confusion.
tion.
blank source, n—source prepared to simulate a test source
Compton baseline, n—baseline in a gamma-ray spectrum,
with no analyte present.
which is due largely to Compton scattering but also in part
branching decay, n—radioactive decay that can proceed in to tailing and other effects.
more than one way.
Compton edge, n—feature of a gamma-ray spectrum which
branching fraction, branching ratio, n—in branching decay, appearsasanabruptdecreaseinthebaselineattheupperend
of the energy distribution of the Compton electrons associ-
the fraction of nuclei that decay in a specified way.
ated with a gamma-ray photopeak.
calibration source, CS, n—a known quantity of radioactive
DISCUSSION—The Compton edge is found at the energy
material,traceabletoanationalstandardsbody,preparedfor
2 2
the purpose of calibrating nuclear instruments. D7282 E ⁄ E 1 m c ⁄2
~ !
γ γ e
where E is the energy of the photopeak.
γ
carrier, n—an isotope or mixture of isotopes of an element,
chemically identical or similar to the radionuclide(s) of
Compton effect, Compton scattering, n—scattering of a
interest, added in a quantity sufficient to promote a desired
photon by a free or weakly bound electron in which the
chemical behavior and move the radionuclide(s) or an
incident photon imparts a portion of its energy and momen-
unwanted contaminant through a chemical process.
tum to the electron, resulting in a free electron and a
scattered lower-energy photon.
DISCUSSION—In radiochemistry the use of a carrier may also allow
gravimetric measurement of the chemical yield.
Compton electron, n—the energetic free electron resulting
from the Compton effect.
cascade summing, (true) coincidence summing,
n—summing produced when the energies of two or more
Compton photon, n—the scattered photon resulting from the
radiations emitted by the same atom are absorbed by the
Compton effect.
detector within a period of time shorter than the resolving
conversion electron, n—the orbital electron ejected from an
time of the detector.
atom by internal conversion.
Ĉerenkov counting, n—radiationcountingtechniquebasedon
coprecipitation, n—precipitation of a normally soluble com-
detection of Ĉerenkov radiation (also Cerenkov or Cheren-
ponent by inclusion in the precipitate of another less soluble
kov).
component from the same solution.
Ĉerenkov radiation, n—electromagnetic radiation emitted by
cosmic radiation, n—radiation that originates outside Earth’s
a charged particle moving through a medium at a speed
atmosphere.
greaterthanthespeedoflightinthatmedium(also Cerenkov
or Cherenkov).
count, (1) v—to perform a radiation counting measurement;
(2) n—a radiation counting measurement;
channel, n—anyofthedataregistersormemorylocationsused
(3) n—a single pulse registered during counting;
to record pulses in a single-channel or multichannel ana-
(4) n—total number of pulses registered during counting.
lyzer.
counting effıciency—see detection efficiency.
chemical yield, n—fractionoftheamountofagivenanalyteor
counting period, counting interval, n—timeintervalfromthe
other substance remaining after specified chemical separa-
tions (sometimes called recovery or chemical recovery). beginning to the end of a radiation counting measurement.
DISCUSSION—Use of the term recovery as a synonym for chemical counting uncertainty, n—inradiochemistry,theuncertaintyof
yield may cause confusion and should be avoided. See recovery.
the result of a measurement due to the random nature of
radioactive decay, radiation emission, and radiation
chemiluminescence, n—emissionofelectromagneticradiation
detection—also called counting error.
as a result of a chemical reaction – a possible cause of
DISCUSSION—The term counting uncertainty is preferred because of
interference in liquid scintillation counting.
the emphasis in metrology on the distinction between error of mea-
surement and uncertainty of measurement.
coincidence counting, n—radiometric counting technique that
lowers interferences by rejecting any event that is not count rate, n—quotient of the total count and the live time for
accompanied by one or more other events occurring within a radiation counting measurement.
D7902 − 14
DISCUSSION—If the count rate is corrected by subtracting a back-
or for a single atom, the probability of decay during a
...
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