ASTM D4785-20

Standard Test Method for Low-Level Analysis of Iodine Radioisotopes in Water

SIGNIFICANCE AND USE
5.1 This test method was developed for measuring low levels of radioactive iodine in water. The results of the test may be used to determine if the concentration of several radioisotopes of iodine in the sample exceeds the regulatory limits for drinking water. With suitable counting techniques, sample size, and counting time, a detection limit of less than 0.037 Bq/L (1 pCi/L) is attainable by gamma-ray spectrometry.  
5.2 This test method is intended for the analysis of iodine radioisotopes with half-lives greater than 2 hours, which include 121I, 123I, 124I, 125I, 126I, 129I, 130I, 131I, 132I, 133I, and 135I. The test method was tested according to Practice D2777 using only 131I. The user of this test method is responsible for determining applicability, bias, and precision for the measurement of other iodine radioisotopes.
SCOPE
1.1 This test method covers the quantification of low levels of radioactive iodine in water by means of chemical separation and counting with a high-resolution gamma ray detector. Iodine is chemically separated from a 4 L water sample using ion exchange and solvent extraction and is then precipitated as cuprous iodide for counting.  
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see 8.16, 8.17, 8.18, Section 9, and 13.2.11.  
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: 30-Apr-2020
• ICS: 13.060.50 - Examination of water for chemical substances
• Technical Committee: D19 - Water
• Drafting Committee: D19.04 - Methods of Radiochemical Analysis

Relations

• Refers: ASTM D7902-20 - Standard Terminology for Radiochemical Analyses
• Effective Date: 01-May-2020

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: D4785 − 20
Standard Test Method for
1
Low-Level Analysis of Iodine Radioisotopes in Water
This standard is issued under the fixed designation D4785; 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 D3649PracticeforHigh-ResolutionGamma-RaySpectrom-
etry of Water
1.1 This test method covers the quantification of low levels
D4448Guide for Sampling Ground-Water MonitoringWells
ofradioactiveiodineinwaterbymeansofchemicalseparation
D5847Practice for Writing Quality Control Specifications
and counting with a high-resolution gamma ray detector.
for Standard Test Methods for Water Analysis
Iodine is chemically separated froma4L water sample using
D6001Guide for Direct-Push Groundwater Sampling for
ion exchange and solvent extraction and is then precipitated as
Environmental Site Characterization
cuprous iodide for counting.
D7282Practice for Set-up, Calibration, and Quality Control
1.2 The values stated in SI units are to be regarded as
of Instruments Used for Radioactivity Measurements
standard. The values given in parentheses after SI units are
D7902Terminology for Radiochemical Analyses
provided for informationonlyandarenotconsideredstandard.
2.2 Other Documents:
1.3 This standard does not purport to address all of the
ANSI N42.22Traceability of Radioactive Sources to the
safety concerns, if any, associated with its use. It is the
National Institute of Standards and Technology (NIST)
responsibility of the user of this standard to establish appro- 3
and Associated Instrument Quality Control
priate safety, health, and environmental practices and deter- 4
BIPM-5Decay Data Evaluation Project (DDEP)
mine the applicability of regulatory limitations prior to use.
5
NUDAT2
For specific hazard statements, see 8.16, 8.17, 8.18, Section 9,
and 13.2.11.
3. Terminology
1.4 This international standard was developed in accor-
dance with internationally recognized principles on standard- 3.1 Definitions:
ization established in the Decision on Principles for the
3.1.1 For definitions of terms used in this standard, refer to
Development of International Standards, Guides and Recom-
Terminology D1129.
mendations issued by the World Trade Organization Technical
3.1.2 For definitions of terms used in this standard relating
Barriers to Trade (TBT) Committee.
to radiochemical analysis, refer to Terminology D7902.
2. Referenced Documents
4. Summary of Test Method
2
2.1 ASTM Standards:
4.1 Sodium iodide is added as a carrier prior to performing
D1129Terminology Relating to Water
any chemical separations. The samples undergo an oxidation-
D1193Specification for Reagent Water
reduction process to ensure exchange between the carrier and
D2777Practice for Determination of Precision and Bias of
the radioactive iodide. Hydroxylamine hydrochloride and so-
Applicable Test Methods of Committee D19 on Water
dium bisulfite are added to convert all the iodine to iodide
D3370Practices for Sampling Water from Flowing Process
which is then removed by anion exchange. Subsequent elution
Streams
of the iodide is followed by oxidation-reduction to elemental
D3648Practices for the Measurement of Radioactivity
iodine. The elemental iodine is purified by solvent extraction,
reduced to iodide, and precipitated as cuprous iodide. The
chemical yield is determined from the net mass of recovered
1
This test method is under the jurisdiction ofASTM Committee D19 on Water
iodide carrier.
andisthedirectresponsibilityofSubcommitteeD19.04onMethodsofRadiochemi-
cal Analysis.
Current edition approved May 1, 2020. Published June 2020. Originally
ɛ1
approved in 1988. Last previous edition approved in 2013 as D4785–13 . DOI:
3
10.1520/D4785-20. Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE),
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 445 Hoes Ln., Piscataway, NJ 08854-4141, http://www.ieee.org.
4
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Available from BIPM, Sèvres Cedex, France, https://www.bipm.org.
5
Standards volume information, refer to the standard’s Document Summary page on Available from National Nuclear Data Center at Brookhaven National
the ASTM website. Laboratory, W Princeton Ave, Yaphank, NY 11980, http://www.nndc.bnl.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D
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This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
´1
Designation: D4785 − 08 (Reapproved 2013) D4785 − 20
Standard Test Method for
1
Low-Level Analysis of Iodine Radioisotopes in Water
This standard is issued under the fixed designation D4785; 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
ε NOTE—Warning notes were editorially updated throughout in June 2013.
1. Scope
1.1 This test method covers the quantification of low levels of radioactive iodine in water by means of chemical separation and
counting with a high-resolution gamma ray detector. Iodine is chemically separated from a 4-L 4 L water sample using ion
exchange and solvent extraction and is then precipitated as cuprous iodide for counting.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for
information purposes only.only and are not considered standard.
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, health, and environmental practices and determine the applicability of
regulatory limitations prior to use. For specific hazard statements, see 8.178.16, 8.188.17, 8.198.18, Section 9, and 13.2.11.
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.
2. Referenced Documents
2
2.1 ASTM Standards:
D1129 Terminology Relating to Water
D1193 Specification for Reagent Water
D2777 Practice for Determination of Precision and Bias of Applicable Test Methods of Committee D19 on Water
D3370 Practices for Sampling Water from Flowing Process Streams
D3648 Practices for the Measurement of Radioactivity
D3649 Practice for High-Resolution Gamma-Ray Spectrometry of Water
D4448 Guide for Sampling Ground-Water Monitoring Wells
D5847 Practice for Writing Quality Control Specifications for Standard Test Methods for Water Analysis
D3856D6001 Guide for Management Systems in Laboratories Engaged in Analysis of WaterDirect-Push Groundwater Sampling
for Environmental Site Characterization
D7282 Practice for Set-up, Calibration, and Quality Control of Instruments Used for Radioactivity Measurements
D7902 Terminology for Radiochemical Analyses
2.2 Other Documents:
ANSI N42.22 Traceability of Radioactive Sources to the National Institute of Standards and Technology (NIST) and Associated
3
Instrument Quality Control
4
BIPM-5 Decay Data Evaluation Project (DDEP)
5
NUDAT2
1
This test method is under the jurisdiction of ASTM Committee D19 on Water and is the direct responsibility of Subcommittee D19.04 on Methods of Radiochemical
Analysis.
Current edition approved June 15, 2013May 1, 2020. Published July 2013June 2020. Originally approved in 1988. Last previous edition approved in 20082013 as
ɛ1
D4785 – 08.D4785 – 13 . DOI: 10.1520/D4785-08R13E01.10.1520/D4785-20.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’sstandard’s Document Summary page on the ASTM website.
3
Available from Institute of Electrical and Electronics Engineers, Inc. (IEEE), 445 Hoes Ln., Piscataway, NJ 08854-4141, http://www.ieee.org.
4
Available from BIPM, Sèvres Cedex, France, https://www.bipm.org.
5
Available from National Nuclear Data Center at Brookhaven National Laboratory, W Princeton Ave, Yaphank, NY 11980, http://www.nndc.bnl.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D4785 − 20
3. Terminology
3.1 Definitions—Definitions: For definitions of terms used in this test method, refer to Terminology D1129.
3.1.1 For definitions of terms used in this standard, refer to Terminology D1129.
3.1.2 For definitions of terms used in this standard relating to radiochemical analysis, refer to Terminology D7902.
4. Summary of Test Method
4.1 Sodium iodide is added as a carrier prior to performing any chemical separations. Th
...