ASTM C1673-10a(2018)

Standard Terminology of C26.10 Nondestructive Assay Methods

SCOPE
1.1 The terminology defined in this document is associated with nondestructive assay of nuclear material.  
1.2 All of the definitions are associated with measurement techniques that measure nuclear emissions (that is, neutrons, gamma-rays, or heat) directly or indirectly.  
1.3 Definitions are relevant to any standards and guides written by subcommittee C26.10.  
1.4 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

• Status: Published
• Publication Date: 31-Mar-2018
• ICS: 17.240 - Radiation measurements
• Technical Committee: C26 - Nuclear Fuel Cycle
• Drafting Committee: C26.10 - Non Destructive Assay

Relations

• Replaces: ASTM C1673-10ae1 - Standard Terminology of C26.10 Nondestructive Assay Methods
• Effective Date: 01-Apr-2018
• Refers: ASTM E456-13a(2022)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2022
• Refers: ASTM E456-13A(2017)e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM E456-13A(2017)e3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Oct-2017
• Refers: ASTM E456-13ae1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13ae2 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13ae3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13a - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Nov-2013
• Refers: ASTM E456-13 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 15-Aug-2013
• Refers: ASTM E456-12 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-May-2012
• Refers: ASTM E456-12e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-May-2012
• Refers: ASTM E456-08e3 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2008
• Refers: ASTM E456-08 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2008
• Refers: ASTM E456-08e2 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2008
• Refers: ASTM E456-08e1 - Standard Terminology Relating to Quality and Statistics
• Effective Date: 01-Apr-2008

Overview

ASTM C1673-10a(2018), Standard Terminology of C26.10 Nondestructive Assay Methods, offers an internationally recognized reference for terminology associated with nondestructive assay (NDA) of nuclear material. Developed by ASTM under the jurisdiction of Committee C26 and Subcommittee C26.10, this standard provides authoritative definitions crucial for professionals engaged in the measurement and assessment of nuclear emissions. The standard supports alignment and clarity in technical communication, facilitating compliance, consistency, and interoperability within the nuclear sector.

ASTM C1673 is especially relevant anywhere nuclear emissions - neutrons, gamma rays, or heat - are measured, directly or indirectly, and underpins standards and guides across the field of nuclear NDA.

Key Topics

• Nondestructive Assay (NDA): Analysis of nuclear material without changing its chemical or physical state; fundamental to nuclear material accounting and management.
• Measurement Techniques: Terminology relates to various NDA techniques measuring gamma-ray, neutron, and heat emissions to quantify nuclear material.
• Key Definitions:
  • Absorber Foils: Materials used to attenuate gamma flux for improved detector response.
  • Assay/Assay Item: Quantitative determination of nuclides; item potentially containing radioisotopes.
  • Calibration Standard/Working Standard: Items with known properties for instrument calibration and routine performance checks.
  • Neutron and Gamma-ray Measurement Terms: Concepts such as coincidence gate length, dead time, multiplicity (singles, doubles, triples), and neutron absorbers/moderators.
  • Matrix and Matrix-Specific Calibration: Bulk material composition and calibration practices relative to matrix effects.
  • Background, Attenuation, and Corrections: Managing signal-to-noise, radiation attenuation, and necessary measurement corrections.
• Quality and Statistical Concepts: Terms covering data quality objectives, control charts, confidence intervals, uncertainty, and traceability ensure robust measurement processes.
• Special Nuclear Materials and Waste: Definitions related to plutonium, uranium, low-level and transuranic waste, waste acceptance criteria, and holdup.

Applications

ASTM C1673-10a(2018) terminology is widely applied in:

• Nuclear Safeguards and Material Control: Ensures precise definitions for regulatory compliance in nuclear material accounting.
• Radioactive Waste Management: Standardizes terms for the classification, measurement, and handling of wastes including low-level and transuranic waste.
• Nuclear Facility Operations: Supports safe, effective measurement of nuclear materials in processing, storage, and decommissioning activities.
• Instrument Development and Calibration: Provides clear reference for developers and users of NDA instrumentation, ensuring correct calibration and operation.
• Quality Assurance Programs: Facilitates the establishment and maintenance of high-confidence measurement systems through robust statistical and technical definitions.
• Research and Training: Acts as a foundational tool for education and ongoing professional development in the nuclear industry.

Related Standards

Professionals employing ASTM C1673 should be aware of these related standards and documents:

• ASTM E456 - Terminology Relating to Quality and Statistics
• DOE Order 435.1 - Low-level Waste Requirements
• DOE Order 5820.2 - Radioactive Waste Management
• Other ASTM C26 Committee Standards - Covering nuclear fuel cycle and NDA methodology

These references together form a core suite aligning technical practice for nondestructive assay and nuclear material management.

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Keywords: nondestructive assay, ASTM C1673, nuclear material, NDA terminology, gamma-ray measurement, neutron detection, nuclear safeguards, radioactive waste, quality assurance, calibration, nuclear facility, ASTM standards

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: C1673 − 10a (Reapproved 2018)
Standard Terminology of
C26.10 Nondestructive Assay Methods
This standard is issued under the fixed designation C1673; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope absorber foils, n—foils, usually of copper, tin, cadmium, or
lead, used to attenuate the gamma flux reaching a detector.
1.1 The terminology defined in this document is associated
DISCUSSION—Absorber foils are used to reduce the count rate,
with nondestructive assay of nuclear material.
typically from intense low-energy X or gamma rays.
1.2 All of the definitions are associated with measurement
accidentals,n—thedetectionofmultipleneutroneventswithin
techniques that measure nuclear emissions (that is, neutrons,
the gate width that are not produced from the same fission.
gamma-rays, or heat) directly or indirectly.
DISCUSSION—Accidental events take their name from the fact that it
1.3 Definitions are relevant to any standards and guides
is the accidental or random summing of neutrons, which are not time
written by subcommittee C26.10. correlated with a common origin (fission or cosmic-ray burst), that give
rise to the appearance of a signature like that from genuine correlated
1.4 This international standard was developed in accor-
events.
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the active assay, n—assay based on the observation of radiation(s)
Development of International Standards, Guides and Recom- induced by irradiation from an external source.
mendations issued by the World Trade Organization Technical
alpha,α,n—the ratio of the uncorrelated neutron emission rate
Barriers to Trade (TBT) Committee.
from (α, n) reactions to the spontaneous neutron emission
rate from a non-multiplying item.
2. Referenced Documents
2.1 ASTM Standards:
aperture, n—the size of the opening in the collimator through
E456 Terminology Relating to Quality and Statistics
which the radiation of interest is intended to pass.
2.2 DOE Orders:
assay, v—to determine quantitatively the amount of one or
DOE Order 435.1 Low-level Waste Requirements
more nuclides of interest contained in an item.
DOE Order 5820.2 Radioactive Waste Management
attenuation correction, n—correction to the measured count
3. Terminology
rate for attenuation of radiation that provides an estimate of
(alpha, n) reaction, n—a reaction that occurs when energetic
the unattenuated radiation emission rate of the radionuclides
alpha particles collide with low atomic number nuclei
being assayed.
resulting in the emission of a neutron.
attenuation, n—reduction of radiation flux due to the interac-
240 240 240
Pu-effective mass, Pu , n—the mass of Pu that
eff
tion of radiation with material between the source of the
would produce the same coincident neutron response in the
radiation and the detector.
instrument as the assay item.
background, n—extraneous signal superimposed on the signal
DISCUSSION—It is a function of the quantity of even mass isotopes of
plutonium in the assay item and fundamental nuclear constants,
of interest.
sometimes referred to as effective Pu mass.
Beers Law, n—the fraction of uncollided gamma rays trans-
mitted through layers of equal thickness of an absorber is a
ThisterminologyisunderthejurisdictionofASTMCommitteeC26onNuclear
constant.
Fuel Cycle and is the direct responsibility of Subcommittee C26.10 on Non
Destructive Assay.
benign matrix,n—bulk material that has a negligible effect on
Current edition approved April 1, 2018. Published May 2018. Originally
ɛ1
approved in 2007. Last previous edition approved in 2010 as C1673 – 10a . DOI:
the result of the measured parameter.
10.1520/C1673-10AR18.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
blank, n—a prepared item containing a matrix as similar as
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
practical to the items being measured that is free, to the
Standards volume information, refer to the standard’s Document Summary page on
extent possible, of the radionuclides of interest.
the ASTM website.
DISCUSSION—The most important matrix parameters are those that
Available from the U.S. Department of Energy (DOE), 1000 Independence
Ave., SW Washington, DC 20585. affect the result of the measurement technique being used.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1673 − 10a (2018)
calibration standard, n—an item similar to the items to be control limits, n—the limits beyond which it is statistically
assayed, for which the parameters of interest and all prop- highlyimprobablethatoneorseveralpoint(s)couldliewhile
erties to which the measurement technique is sensitive are the system remains in a state of statistical control.
known.
data quality objective, n—measurement uncertainty and con-
calorimeter, n—a device to measure heat or rate-of-heat
fidence levels specified by the scope of work.
generation.
dead time, n—the period following the detection of an event
calorimetric assay, n—determination of the mass of radioac-
during which the detection electronics cannot register a
tive material through the measurement of its thermal power
subsequent event.
by calorimetry and the use of nuclear decay constants and, if
DISCUSSION—Dead time is usually expressed as a percentage of
necessary, additional isotopic measurements. elapsed time.
certification, n—a written declaration from a certifying body
delayed neutrons, n—neutrons emitted by the item that are
or its legitimate designee that a particular measurement produced from decay of the fission products.
process or measurement personnel comply with stated crite-
DISCUSSION—These neutrons are produced at a time after the initial
fission event.
ria or that a measured item has the stated characteristics.
code validation, n—process to determine that the software depleted uranium, n—uranium containing less than the natu-
performs its intended functions correctly, ensure that it rally occurring fraction of U isotopes (<0.7 weight
performs no unintended functions, and provides information percent).
about its quality and reliability.
die-away time, n—the average life time of the neutron
coincidence gate length, n—the time interval following the
population as measured from the time of emission to
detection of a neutron during which additional neutrons are detection, escape, or absorption. The average lifetime is the
considered to be in coincidence with the original neutron.
time required for the neutron population to decrease by a
factor of 1/e.
coincident neutrons, n—two or more neutrons emitted simul-
taneously from a single event, such as from a nucleus during
doubles, n—the detection of neutron pairs produced from the
fission.
same fission event.
DISCUSSION—The doubles terminology is often used in reference to
collimated detector, n—a detector surrounded by a shield that
multiplicity counting, but it is the same as the reals from coincidence
imposes a directional response on the collimated detector.
counting.
collimator, n—a shield that imposes a directional response on
effective specific power, p , n—the rate of energy emission
eff
the detector. Generally, for gamma ray detection the colli-
per unit mass of radionuclide at the time of measurement.
mator is a hollow cylinder or rectangular prism of high
far-field measurement, n—a measurement geometry where
atomic number (Z) and high density material, mounted
coaxially to the detector and extending over the detector and the analyst can assume that all gamma rays emitted from the
item enter the detector along paths parallel to each other.
beyond the detector face.
Compton scattering,n—scattering of gamma rays that may or field of view, n—the entire solid angle subtended by the
may not be from the radionuclide of interest. collimated detector.
DISCUSSION—Thescatteringreducestheenergyofthegammarayand
fissile isotopes, n—isotopes that can be induced to fission by
results in a continuum of gamma ray energies.
thermal neutrons.
computed tomography, n—see tomography. 233 235 239 241
DISCUSSION— U, U, Pu, and Pu are the most common
fissile isotopes.
confidence interval, n—the range of values, calculated from
the probability distribution (often sufficiently well character-
flux monitors, n—detectors in the measurement chamber that
ized by the estimate of the mean and standard deviation),
measure the neutron flux of interrogating neutrons (cavity
which is expected to include the population mean with a
flux monitor) or item neutrons (drum flux monitor).
stated level of confidence or likelihood.
heat-flow calorimeter,n—acalorimetersoconstructedthatthe
DISCUSSION—For more details see Test Method E456.
heat generated in the calorimeter flows past a temperature
contact measurement, n—a special case of a near-field mea-
sensing element, through a thermal resistance, to a constant
surement in which measurements are made with the detector
temperature heat sink.
assembly in contact with the item, for example, tank, pipe,
holdup, n—the residual nuclear material remaining in process
ductwork, being assayed.
equipmen
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