ASTM C1316-08(2017)
(Test Method)Standard Test Method for Nondestructive Assay of Nuclear Material in Scrap and Waste by Passive-Active Neutron Counting Using 252Cf Shuffler
Standard Test Method for Nondestructive Assay of Nuclear Material in Scrap and Waste by Passive-Active Neutron Counting Using <sup>252</sup>Cf Shuffler
SIGNIFICANCE AND USE
5.1 This test method is used to determine the U and Pu content of scrap and waste in containers. Active measurement times have typically been 100 to 1000 s. Passive measurement times have typically been 400 s to several hours. The following limits may be further restricted depending upon specific matrix, calibration material, criticality safety, or counting equipment considerations.
5.1.1 The passive measurement has been applied to benign matrices in 208 L drums with Pu content ranging from 30 mg to 1 kg.
5.1.2 The active measurement has been applied to waste drums with 235U content ranging from about 100 mg to 1 kg.
5.2 This test method can be used to demonstrate compliance with the radioactivity levels specified in safeguards, waste, disposal, and environmental regulations (for example, see NRC regulatory guides 5.11, 5.53, DOE Order 5820.2a, and 10CFR61 sections 61.55 and sections 61.56, 40CFR191, and DOE/WIPP-069).
5.3 This test method could be used to detect diversion attempts that use shielding to encapsulate nuclear material.
5.4 The bias of the measurement results is related to the item size and density, the homogeneity and composition of the matrix, and the quantity and distribution of the nuclear material. The precision of the measurement results is related to the quantity of nuclear material and the count time of the measurement.
5.4.1 For both the matrix-specific and the matrix-correction approaches, the method assumes the calibration materials match the items to be measured with respect to the homogeneity and composition of the matrix, the neutron moderator and absorber content, and the quantity of nuclear material, to the extent they affect the measurement.
5.4.2 It is recommended that measurements be made on small containers of scrap and waste before they are combined in large containers. Special arrangement may be required to assay small containers to best effect in a large cavity general purpose shuffer.
5.4.3 It is recommend...
SCOPE
1.1 This test method covers the nondestructive assay of scrap and waste items for U, Pu, or both, using a 252 Cf shuffler. Shuffler measurements have been applied to a variety of matrix materials in containers of up to several 100 L. Corrections are made for the effects of matrix material. Applications of this test method include measurements for safeguards, accountability, TRU, and U waste segregation, disposal, and process control purposes (1, 2, 3).2
1.1.1 This test method uses passive neutron coincidence counting (4) to measure the 240Pu-effective mass. It has been used to assay items with total Pu contents between 0.03 g and 1000 g. It could be used to measure other spontaneously fissioning isotopes such as Cm and Cf. It specifically describes the approach used with shift register electronics; however, it can be adapted to other electronics.
1.1.2 This test method uses neutron irradiation with a moveable Cf source and counting of the delayed neutrons from the induced fissions to measure the 235U equivalent fissile mass. It has been used to assay items with 235U contents between 0.1 g and 1000 g. It could be used to assay other fissile and fissionable isotopes.
1.2 This test method requires knowledge of the relative isotopic composition (See Test Method C1030) of the special nuclear material to determine the mass of the different elements from the measurable quantities.
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 The techniques described in this test method have been applied to materials other than scrap and waste. These other applications are not addressed in this test method.
1.5 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 applicab...
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: C1316 − 08 (Reapproved 2017)
Standard Test Method for
Nondestructive Assay of Nuclear Material in Scrap and
Waste by Passive-Active Neutron Counting Using Cf
Shuffler
This standard is issued under the fixed designation C1316; 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 1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
1.1 This test method covers the nondestructive assay of
252 responsibility of the user of this standard to establish appro-
scrapandwasteitemsforU,Pu,orboth,usinga Cfshuffler.
priate safety and health practices and determine the applica-
Shufflermeasurementshavebeenappliedtoavarietyofmatrix
bility of regulatory limitations prior to use. Specific precau-
materials in containers of up to several 100 L. Corrections are
tionary statements are given in Section 8.
madefortheeffectsofmatrixmaterial.Applicationsofthistest
method include measurements for safeguards, accountability,
2. Referenced Documents
TRU, and U waste segregation, disposal, and process control
2.1 ASTM Standards:
purposes (1, 2, 3).
C1009Guide for Establishing and Maintaining a Quality
1.1.1 This test method uses passive neutron coincidence
AssuranceProgramforAnalyticalLaboratoriesWithinthe
counting (4) to measure the Pu-effective mass. It has been
Nuclear Industry
used to assay items with total Pu contents between 0.03 g and
C1030TestMethodforDeterminationofPlutoniumIsotopic
1000 g. It could be used to measure other spontaneously
Composition by Gamma-Ray Spectrometry
fissioningisotopessuchasCmandCf.Itspecificallydescribes
C1068Guide for Qualification of Measurement Methods by
the approach used with shift register electronics; however, it
a Laboratory Within the Nuclear Industry
can be adapted to other electronics.
C1128Guide for Preparation of Working Reference Materi-
1.1.2 This test method uses neutron irradiation with a
als for Use in Analysis of Nuclear Fuel Cycle Materials
moveableCfsourceandcountingofthedelayedneutronsfrom
C1133Test Method for Nondestructive Assay of Special
the induced fissions to measure the U equivalent fissile
Nuclear Material in Low-Density Scrap and Waste by
mass. It has been used to assay items with U contents
Segmented Passive Gamma-Ray Scanning
between0.1gand1000g.Itcouldbeusedtoassayotherfissile
C1156Guide for Establishing Calibration for a Measure-
and fissionable isotopes.
ment Method Used toAnalyze Nuclear Fuel Cycle Mate-
1.2 This test method requires knowledge of the relative
rials
isotopic composition (See Test Method C1030) of the special
C1207Test Method for NondestructiveAssay of Plutonium
nuclearmaterialtodeterminethemassofthedifferentelements
in Scrap and Waste by Passive Neutron Coincidence
from the measurable quantities.
Counting
1.3 The values stated in SI units are to be regarded as
C1210Guide for Establishing a Measurement System Qual-
standard. No other units of measurement are included in this
ity Control Program for Analytical Chemistry Laborato-
standard.
ries Within the Nuclear Industry
C1215Guide for Preparing and Interpreting Precision and
1.4 The techniques described in this test method have been
Bias Statements in Test Method Standards Used in the
applied to materials other than scrap and waste. These other
Nuclear Industry
applications are not addressed in this test method.
C1490GuidefortheSelection,TrainingandQualificationof
Nondestructive Assay (NDA) Personnel
ThistestmethodisunderthejurisdictionofASTMCommitteeC26onNuclear
C1592Guide for Nondestructive Assay Measurements
Fuel Cycle and is the direct responsibility of Subcommittee C26.10 on Non
Destructive Assay.
Current edition approved Jan. 1, 2017. Published January 2017. Originally
approved in 1995. Last previous edition approved in 2008 as C1316–08. DOI: For referenced ASTM standards, visit the ASTM website, www.astm.org, or
10.1520/C1316-08R17. contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
The boldface numbers in parentheses refer to a list of references at the end of Standards volume information, refer to the standard’s Document Summary page on
this test method. the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1316 − 08 (2017)
C1673Terminology of C26.10 NondestructiveAssay Meth- 4.2 Either corrections are made for the effects of neutron
ods absorbers and moderators in the matrix, or a matrix-specific
calibration is used. The effect that needs correction is the
2.2 ANSI Documents:
ANSI 15.20Guide to Calibrating Nondestructive Assay increaseordecreaseinthespecificneutronsignalcausedbythe
matrix.
Systems
ANSI N15.36Nondestructive Assay Measurement Control
4.3 Correctionsaremadefordeadtime,neutronbackground,
and Assurance
and the Cf source decay.
3. Terminology
4.4 The active mode also induces fissions in Pu if it is
present in the assay item. The passive measurement of Pu can
3.1 Definitions—Terms shall be defined in accordance with
be used to correct the active measurement of U effective for
Terminology C1673.
the presence of Pu.
3.2 Definitions of Terms Specific to This Standard:
4.5 Calibrations are generally based on measurements of
3.2.1 active mode, n—determines total fissile mass in the
well documented reference materials (8) and may be extended
assayeditemthroughneutroninterrogationandcountingofthe
delayed neutrons from induced fissions. by calculation (9-11). The method includes measurement
control tests to verify reliable and stable performance of the
4. Summary of Test Method
instrument.
4.1 This test method consists of two distinct modes of
5. Significance and Use
operation:passiveandactive.Theinstrumentthatperformsthe
active mode measurement is referred to as a shuffler due to the
5.1 This test method is used to determine the U and Pu
cyclic motion of the Cf source. This test method usually
content of scrap and waste in containers.Active measurement
reliesonpassiveneutroncoincidencecountingtodeterminethe
times have typically been 100 to 1000 s. Passive measurement
Pu content of the item, and active neutron irradiation followed
timeshavetypicallybeen400stoseveralhours.Thefollowing
by delayed neutron counting to determine the U content.
limits may be further restricted depending upon specific
4.1.1 Passive Neutron Coincidence Counting Mode—The
matrix, calibration material, criticality safety, or counting
even mass isotopes of Pu fission spontaneously. On average
equipment considerations.
approximately2.2promptneutronsareemittedperfission.The
5.1.1 The passive measurement has been applied to benign
number of coincident fission neutrons detected by the instru-
matrices in 208 L drums with Pu content ranging from 30 mg
ment is correlated to the quantity of even mass isotopes of Pu.
to 1 kg.
ThetotalPumassisdeterminedfromtheknownisotopicratios
5.1.2 The active measurement has been applied to waste
and the measured quantity of even mass isotopes. This test
drums with U content ranging from about 100 mg to 1 kg.
method refers specifically to the shift register coincidence
counting electronics (see (4) and Test Method C1207).
5.2 Thistestmethodcanbeusedtodemonstratecompliance
4.1.2 Active Neutron (Shuffler) Mode—Fissions
with the radioactivity levels specified in safeguards, waste,
235 239
in U, Pu and other fissile nuclides can be induced by
disposal,andenvironmentalregulations(forexample,seeNRC
bombarding them with neutrons. Approximately 1% of the
regulatory guides 5.11, 5.53, DOE Order 5820.2a, and
neutrons emitted per fission are delayed in time, being emitted
10CFR61 sections 61.55 and sections 61.56, 40CFR191, and
fromthefissionproductsoverthetimerangefromµstoseveral
DOE/WIPP-069).
minutes after the fission event. Roberts et. al (5) were the first
5.3 This test method could be used to detect diversion
to observe delayed neutron emission. We now know that over
attempts that use shielding to encapsulate nuclear material.
270delayedneutronprecursorscontributetotheyieldalthough
the time behavior can be adequately described for most 5.4 The bias of the measurement results is related to the
purposes using a few (six to eight) effective groups each with item size and density, the homogeneity and composition of the
a characteristic time constant. The idea of detecting delayed matrix, and the quantity and distribution of the nuclear mate-
neutrons for the analysis of U has been attributed to Echo rial. The precision of the measurement results is related to the
and Turk (6). The active shuffler mode consists of several quantity of nuclear material and the count time of the mea-
irradiate-count cycles, or shuffles, of the Cf neutron source surement.
betweenthepositionsillustratedinFig.1. Cfemitsafission
5.4.1 For both the matrix-specific and the matrix-correction
neutron spectrum. During each shuffle, the Cf source is
approaches, the method assumes the calibration materials
moved close to the item for a short irradiation, then moved to
match the items to be measured with respect to the homoge-
ashieldedpositionwhilethedelayedneutronsarecounted.The
neityandcompositionofthematrix,theneutronmoderatorand
number of delayed neutrons detected is correlated with the
absorber content, and the quantity of nuclear material, to the
quantity of fissile and fissionable material.The total U mass is
extent they affect the measurement.
determined from the known relative isotopic compostion and
5.4.2 It is recommended that measurements be made on
the measured quantity of U equivalent (7).
small containers of scrap and waste before they are combined
in large containers. Special arrangement may be required to
assay small containers to best effect in a large cavity general
Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
4th Floor, New York, NY 10036, http://www.ansi.org. purpose shuffer.
C1316 − 08 (2017)
NOTE 1—The shuffler measurement consists of several cycles. Each cycle includes the movement of the Cf source from the storage (or home)
position to the irradiation position close to the item, irradiation of the item for a period of about 10 s, return of the source to the shield followed by a
counting period of about 10 s. In obvious notation this cycle structure may be succinctly described by the four time periods involved (t ,t ,t ,t ).
in irr out cnt
Typically the one-way transit times are less than 1 s.
FIG. 1 Cf Shuffler Measurement Principle
C1316 − 08 (2017)
5.4.3 It is recommended that measurements be made on 6.3.1 Active Mode (Self-Shielding)—The nuclear material
containers with homogeneous contents. In general, heteroge- on the surface of the lump shields the inside of the lump from
neity in the distribution of nuclear material, neutron the interrogating neutrons (15, 16).
moderators, and neutron absorbers has the potential to cause 6.3.2 Passive Mode (Multiplication)—Neutrons originating
biased results.
in the lump induce fissions in the same lump which boosts the
specific coincident rate.
5.5 This test method requires that the relative isotopic
compositions of the contributing elements are known.
6.4 Moderators in the matrix can cause a bias in the
measurement results, unless a correction is made or an appro-
5.6 This test method assumes that the distribution of the
priate matrix specific calibration is used. The magnitude and
contributingisotopesisuniformthroughoutthecontainerwhen
direction of this bias depend on the quantity of moderator
the matrix affects neutron transport.
present, the distribution of the fissile material, and the size of
5.7 This test method assumes that lump affects are
the item (2, 17).
unimportant—that is to say that large quantities of special
6.4.1 Although moderation is the greatest potential source
nuclear material are not concentrated in a small portion of the
of bias for passive measurements, the passive method is
container.
generallylesssusceptibletothepresenceofmoderatorthanthe
5.8 Forbestresultsfromtheapplicationofthistestmethod,
active method.
appropriate packaging of the items is required. Suitable train-
6.4.2 Thepresenceofabsorbersinthematrixcancausebias
ing of the personnel who package the scrap and waste prior to
if there is sufficient moderator present. The moderator slows
measurement should be provided (for example, see ANSI
fast neutrons which can then be captured more effectively by
15.20, Guide C1009, Guide C1490, and Guide C1068 for
the absorbers.
training guidance). Sometimes site specific conditions and
6.4.3 The instrument produces a nonuniform response
requirements may have greater bearing.
across the container, the severity varying with the concentra-
tion of hydrogen in the matrix. A source at the center of the
6. Interferences
container can produce either a higher or lower response than
6.1 Potential sources of measurement interference include
the same source located at the surface of the container
unexpected nuclear material contributing to the active or
depending on the item and instrument design.
passive neutron signal, self-shielding by lumps of fissile
6.5 Background neutron count rates from cosmic ray-
material, neutron self-multiplication, excessive quantities of
induced spallation can degrade the measurement sensitivity
absorbers or moderators in the matrix, heterogeneity of the
(detection limit) and the measurement precision for small
matrix, and the non-uniformity of the nuclear material spatial
masses (18, 19).
distribution especially within a moderating matrix. In general,
the greatest potential source of bias for active neutron mea-
6.6 High-background count rates mask the instrument re-
surement is heterogeneity of the nuclear material within a sponse to small quantities of special nuclear material for both
highly moderating matrix, while the greatest for passive
the active and passive modes (20-22).
neutron measurement is neutron moderation and absorption
6.7 High gamma dose rates eminating from the item (>10
(12).
–1
mSv h of penetrating radiation) may cause pile-up and
6.2 The techniques described in this test method cannot
break-down in the He-filled proportional neutron detectors
distinguishwhichisotopeisgeneratingthemeasuredresponse.
(23). Care should be taken
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.