ASTM C1205-20

Standard Test Method for The Radiochemical Determination of Americium-241 in Soil by Alpha Spectrometry

SIGNIFICANCE AND USE
5.1 This test method provides the speed and high decontamination factors attainable with liquid-liquid extraction of the actinides and eliminates filtration techniques that are more time consuming.  
5.2 This test method provides a precise determination of americium in concentrations normally found in environmental samples.
SCOPE
1.1 This test method covers the determination of 241Am in soil by means of chemical separations and alpha spectrometry. It is designed to analyze up to 10 g of soil or other sample matrices that contain up to 30 mg of combined rare earths. This test method allows the determination of 241Am concentrations from ambient levels to applicable standards.  
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.  
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-Nov-2020
• ICS: 27.120.30 - Fissile materials and nuclear fuel technology
• Technical Committee: C26 - Nuclear Fuel Cycle
• Drafting Committee: C26.05 - Methods of Test

Relations

• Refers: ASTM C859-24 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Jan-2024
• Refers: ASTM C998-17 - Standard Practice for Sampling Surface Soil for Radionuclides
• Effective Date: 01-Jun-2017
• Refers: ASTM C999-17 - Standard Practice for Soil Sample Preparation for the Determination of Radionuclides
• Effective Date: 01-Jun-2017
• Refers: ASTM C859-14a - Standard Terminology Relating to Nuclear Materials
• Effective Date: 15-Jun-2014
• Refers: ASTM C859-14 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 15-Jan-2014
• Refers: ASTM C859-13a - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Jun-2013
• Refers: ASTM C859-13 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-May-2013
• Refers: ASTM D3084-05(2012) - Standard Practice for Alpha-Particle Spectrometry of Water
• Effective Date: 01-Jun-2012
• Refers: ASTM D3648-04(2011) - Standard Practices for the Measurement of Radioactivity
• Effective Date: 01-Jan-2011
• Refers: ASTM C859-10b - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Nov-2010
• Refers: ASTM C859-10a - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Aug-2010
• Refers: ASTM C999-05(2010)e1 - Standard Practice for Soil Sample Preparation for the Determination of Radionuclides
• Effective Date: 01-Jun-2010
• Refers: ASTM C998-05(2010)e1 - Standard Practice for Sampling Surface Soil for Radionuclides
• Effective Date: 01-Jun-2010
• Refers: ASTM C859-10 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 01-Feb-2010
• Refers: ASTM C859-09 - Standard Terminology Relating to Nuclear Materials
• Effective Date: 15-Feb-2009

Overview

ASTM C1205-20 is the Standard Test Method for the Radiochemical Determination of Americium-241 in Soil by Alpha Spectrometry. Developed by ASTM International, this standard outlines precise procedures for identifying and quantifying americium-241 (Am-241) in soil and similar matrices. The method employs chemical separations and alpha spectrometric analysis, ensuring accurate measurement of Am-241 from ambient levels up to regulated standards. Emphasizing speed and high decontamination through liquid-liquid extraction, ASTM C1205-20 is pivotal for laboratories engaged in environmental radioanalytical testing.

Key Topics

• Purpose and Scope

  • Outlines procedures for determining Am-241 concentrations in up to 10 grams of soil or matrices with up to 30 mg of combined rare earths.
  • Suitable for a wide range of concentration levels typically found in environmental samples.

• Test Method

  • Utilizes chemical separation methods including pyrosulfate fusion, organophosphorous extraction, oxidation, and precipitation.
  • Final analysis is performed using alpha spectrometry with neodymium fluoride mounting for high resolution.

• Precision and Accuracy

  • Proven relative standard deviation of 6%, ensuring reliable and reproducible results.
  • Validated with reference materials and control standards for laboratory quality assurance.

• Safety Considerations

  • Addresses significant safety concerns related to the use of hazardous reagents such as hydrofluoric and perchloric acids.
  • Requires appropriate laboratory controls, personal protective equipment, and adherence to safety data sheets.

• Calculation and Standardization

  • Provides formulas for calculating Am-241 concentration and its standard deviation.
  • Utilizes tracers (typically Am-243) for yield monitoring.

Applications

ASTM C1205-20 is essential in sectors where accurate radiochemical analysis of environmental samples is required, including:

• Environmental Monitoring

  • Assessing contamination in areas impacted by nuclear activities or radioactive fallout.
  • Supporting site remediation and compliance with environmental regulations.

• Nuclear Facility Assessments

  • Determining surface soil radioactivity at decommissioned reactor or waste storage sites.
  • Ongoing monitoring of operational nuclear facilities for safety and regulatory adherence.

• Radioecology and Research

  • Supporting scientific studies of transuranic elements distribution and behavior in soils.
  • Contributing data for risk assessment models on radiological contamination.

• Quality Assurance in Environmental Laboratories

  • Standardizing test methods to ensure comparability of results across institutions.
  • Verifying laboratory performance using certified reference materials.

Related Standards

For comprehensive radiochemical soil analysis and alpha spectrometry, the following ASTM standards are referenced within ASTM C1205-20:

• ASTM C859 - Terminology Relating to Nuclear Materials
• ASTM C998 - Practice for Sampling Surface Soil for Radionuclides
• ASTM C999 - Practice for Soil Sample Preparation for Radionuclides
• ASTM C1163 - Practice for Mounting Actinides for Alpha Spectrometry Using Neodymium Fluoride
• ASTM D1193 - Specification for Reagent Water
• ASTM D3084 - Practice for Alpha-Particle Spectrometry of Water
• ASTM D3648 - Practices for the Measurement of Radioactivity

Summary

ASTM C1205-20 delivers a validated, standardized approach for quantifying americium-241 in soil using alpha spectrometry, ensuring regulatory compliance, safety, and analytical precision. Laboratories and organizations conducting environmental radioanalytical testing will benefit from the robust methodology, clear procedural guidance, and integration with related standards for comprehensive radiochemical analysis.

Keywords: alpha spectrometry, americium-241, radiochemical determination, environmental testing, ASTM C1205-20, soil analysis, liquid-liquid extraction, neodymium fluoride mounting.

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: C1205 − 20
Standard Test Method for
The Radiochemical Determination of Americium-241 in Soil
by Alpha Spectrometry
This standard is issued under the fixed designation C1205; 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 D3648 Practices for the Measurement of Radioactivity
1.1 This test method covers the determination of Am in
3. Terminology
soil by means of chemical separations and alpha spectrometry.
3.1 Definitions:
It is designed to analyze up to 10 g of soil or other sample
3.1.1 Except as otherwise defined herein, definitions of
matricesthatcontainupto30mgofcombinedrareearths.This
terms are as given in Terminology C859.
test method allows the determination of Am concentrations
from ambient levels to applicable standards.
4. Summary of Test Method
1.2 The values stated in SI units are to be regarded as
4.1 Americium-241 is determined in prepared soil samples
standard. The values given in parentheses after SI units are
of up to 10 g. The soil is completely dissolved by use of
provided for information only and are not considered standard.
pyrosulfate fusion.After an initial separation on barium sulfate
1.3 This standard does not purport to address all of the
and extraction with an organophosphorous compound, the
safety concerns, if any, associated with its use. It is the
americium is separated from the other trivalent actinides and
responsibility of the user of this standard to establish appro-
the rare earths by oxidation of the americium and precipitation
priate safety, health, and environmental practices and deter-
of the interferences. The americium is prepared for alpha
mine the applicability of regulatory limitations prior to use.
spectrometry by coprecipitation with neodymium fluoride and
1.4 This international standard was developed in accor-
241 243
the Am determined by alpha spectrometry using Am as a
dance with internationally recognized principles on standard-
yield monitor.
ization established in the Decision on Principles for the
4.2 Typical radiochemical recoveries of this test method as
Development of International Standards, Guides and Recom-
determined by the yield monitor, are between 75 and 90 %.
mendations issued by the World Trade Organization Technical
Decontamination factors from other radionuclides that may
Barriers to Trade (TBT) Committee.
interfere with the determination of americium in this energy
4 5
2. Referenced Documents range are 10 –10 .
2 243
2.1 ASTM Standards: 4.3 The reagent blank contains all reagents plus the Am
C859 Terminology Relating to Nuclear Materials tracer. Five samples and a reagent blank can be completed and
C998 Practice for Sampling Surface Soil for Radionuclides ready for alpha spectrometry in approximately 6 h. The
C999 Practice for Soil Sample Preparation for the Determi- full-width at half-maximum (FWHM) detector resolution
nation of Radionuclides ranges between 43 and 65 keV.
C1163 Practice for MountingActinides forAlpha Spectrom-
5. Significance and Use
etry Using Neodymium Fluoride
D1193 Specification for Reagent Water
5.1 This test method provides the speed and high decon-
D3084 Practice for Alpha-Particle Spectrometry of Water
tamination factors attainable with liquid-liquid extraction of
the actinides and eliminates filtration techniques that are more
time consuming.
This test method is under the jurisdiction ofASTM Committee C26 on Nuclear
Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of
5.2 This test method provides a precise determination of
Test.
americium in concentrations normally found in environmental
Current edition approved Dec. 1, 2020. Published February 2021. Originally
samples.
approved in 1991. Last previous edition approved in 2012 as C1205 – 07 (2012).
DOI: 10.1520/C1205-20.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 6. Interferences
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
6.1 Plutonium, if inadequately separated, may interfere with
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. the alpha spectrometric determination of Am. Thorium-228,
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1205 − 20
identifiable by its progeny, is a serious interference to the final 8.2 Purity of Water—Unless otherwise indicated, reference
determination of americium by alpha spectrometry if decon- to water shall be understood to mean reagent water as defined
tamination factors are not sufficiently high. An inadequate in Specification D1193, Type III or better.
separation of Po may result in an inaccurate determination 243 3
8.3 Americium Tracer—Purify the Am tracer. The
of the Am yield monitor but this is unlikely when using the 243
Am tracer may be available from NIST or other recognized
neodymium fluoride precipitation method. If high concentra-
standards laboratories.
tions of these radionuclides are known to be present, a
8.4 Potassium Fluoride, anhydrous.
preliminary separation may be required.
8.5 Potassium Sulfate, anhydrous.
7. Apparatus
8.6 Sodium Sulfate, anhydrous.
7.1 Alpha pulse height analysis system as in Practice
8.7 Ammonium Persulfate (ammonium peroxydisulfate).
D3084.
8.8 Hydrochloric Acid (sp gr 1.19)—Concentrated hydro-
7.1.1 Asystem consisting of a silicon surface barrier detec-
chloric acid (HCl).
tor capable of 50 keV or better resolution on standards
8.9 Hydrofluoric Acid (sp gr 1.20)—Concentrated hydroflu-
electrodeposited on a flat, mirror finished disk is required.
oric acid (HF).
Samples prepared for alpha spectrometry using neodymium
fluoride mounting by Practice C1163 should be capable of 60
8.10 Sulfuric Acid (sp gr 1.84)—Concentrated sulfuric acid
to 70 keV resolution. The resolution is defined as the width of
(H SO ).
2 4
analphaenergypeakwhenthecountsoneithersideofthepeak
8.11 Sulfuric Acid Solution 0.5 %—Mix 5 mL of concen-
are equal to one-half of the counts at the maximum of the peak
trated sulfuric acid with water and dilute to 1 L.
(FWHM).
8.12 Nitric Acid (sp gr 1.42)—Concentrated nitric acid
7.1.2 The counting efficiency of the system (that is, count/
(HNO ).
disintegration) should be greater than 20 % and the instrument 3
background in the region of each energy peak used for analysis
8.13 Potassium Metabisulfite Solution 25 %—Dissolve
should be less than five counts in 60 000 s (1000 min).
25 g of potassium metabisulfite in water and dilute to 100 mL.
7.2 Membrane Filter (such as cellulose nitrate or cellulose
8.14 Sodium Bromate Solution 10 %—Dissolve 10 g of
acetate), 47 mm diameter, 0.45 µm pore size. sodium bromate in water and dilute to 100 mL.
7.3 Platinum dish, 250 mL. 8.15 HDEHP Solution 15 %—Dissolve 150 mL of bis(2-
ethylhexyl)phosphoric acid in 850 mL of n-heptane.
7.4 Blast burner.
8.16 Barium Chloride Solution 0.5 %—Dissolve 0.5 g of
7.5 Ring stand.
barium chloride in water and dilute to 100 mL.
7.6 Glass beaker, 800 mL.
8.17 5M Nitric Acid—Mix 312 mL of concentrated nitric
acid with water and dilute to 1 L.
7.7 Hot plate with fiberglass mat cover.
8.18 Silver Nitrate Solution 0.5 %—Dissolve 0.5 g of silver
7.8 Erlenmeyer flask, 125 mL.
nitrate in water and dilute to 100 mL.
7.9 Separatory funnel, 60 mL.
8.19 Lanthanum Carrier (5 mg La/mL)— Dissolve 1.17 g of
7.10 Polycarbonate counting bottle, 70 mL.
lanthanum nitrate in 75 mL of 5M nitric acid and dilute to
100 mL with water.
7.11 Centrifuge.
8.20 Phosphoric Acid (sp gr 1.83)—Concentrated phos-
7.12 Hot water bath.
phoric acid (H PO ).
3 4
7.13 Tetrafluoroethylene (TFE) fluorocarbon beaker.
8.21 0.2MAmmonium Persulfate—Dissolve 2.3 g of ammo-
7.14 Conical polycarbonate centrifuge tube, 50 mL.
nium persulfate in water and dilute to 50 mL. Prepare daily.
7.15 Round bottom polycarbonate centrifuge tube, 50 mL.
8.22 6M Ammonium Fluoride—Dissolve 22.2 g of ammo-
nium fluoride in water and dilute to 100 mL.
7.16 Ice water bath.
8.23 0.10M Ammonium Persulfate-3N Ammonium
Fluoride—Mix 20 mL of 0.2M ammonium persulfate with
8. Reagents and Materials
20 mL of 6M ammonium fluoride. Prepare daily.
8.1 Purity of Reagents—Reagent grade chemicals shall be
8.24 Hydrogen Peroxide Solution 30 %.
used in all tests. Unless otherwise indicated, it is intended that
all reagents shall conform to the specifications of the Commit-
8.25 Perchloric Acid (sp gr 1.67)—Concentrated perchloric
tee onAnalytical Reagents of theAmerican Chemical Society,
acid (HClO ).
where such specifications are available. Other grades may be
used, provided it is first ascertained that the reagent is of
sufficiently high purity to permit its use without lessening the
For a description of this process, see Sill, C. W., Analytical Chemistry, 46,
accuracy of the determination. 1974, pp. 1426–1431.
C1205 − 20
8.26 Neodymium Carrier (10 mg Nd/mL)—Heat 25 mL of burner until the contents have dissolved completely. Swirl the
12M hydrochloric acid and 1.17 g of neodymium oxide on a contents gently to dissolve any sample on the sides of the dish.
hot plate until the neodymium oxide is in solution. Cool the When the sample has dissolved completely, carefully remove
solution and dilute to 100 mL with water. the platinum dish from the ring stand and swirl the melt as it
cools to deposit the melt evenly along the sides and the bottom
8.27 Neodymium Carrier (0.5 mg Nd/mL)—Dilute 5 mL of
of the dish.
the 10 mg Nd/mL neodymium carrier solution to 100 mL with
water.
12.2 After the contents of the dish have cooled to room
temperature, carefully add 40 mLof concentrated sulfuric acid
9. Sampling
to transpose the fluoride cake. After the initial vigorous
9.1 Collect the sample in accordance with Practice C998.
reaction has subsided, place the dish on a fiberglass mat-
covered hot plate and heat until the fluoride cake has been
9.2 Prepare the sample for analysis in accordance with
completely transposed.Add 20 g of anhydrous sodium sulfate,
Practice C999.
place the dish on the ring stand and heat gently until the
10. Hazards
viscous solution begins to boil. Increase the temperature from
the blast burner until a smooth boiling mixture is obtained and
10.1 In addition to other precautions, adequate laboratory
continue heating until a clear melt results. Cool the dish to
facilities, such as perchloric acid fume hoods and controlled
solidify the melt and then place the dish into a cold water bath
ventilation, along with safe techniques must be used in this
to facilitate cake removal.
procedure. Extreme care should be exercised in using hydro-
fluoric acid and other hot concentrated acids, particularly hot
12.3 Bring 500 mL of water and 150 mL of concentrated
perchloric acid. Use of safety equipment, especially safety
hydrochloric acid to a boil in a 800 mL beaker and carefully
g
...

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.
Designation: C1205 − 07 (Reapproved 2012) C1205 − 20
Standard Test Method for
The Radiochemical Determination of Americium-241 in Soil
by Alpha Spectrometry
This standard is issued under the fixed designation C1205; 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
1.1 This test method covers the determination of americium–241Am in soil by means of chemical separations and alpha
spectrometry. It is designed to analyze up to ten grams 10 g of soil or other sample matrices that contain up to 30 mg of combined
rare earths. This test method allows the determination of americium–241Am concentrations from ambient levels to applicable
standards. The values stated in SI units are to be regarded as standard.
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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.For specific precaution statements, see Section 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.
2. Referenced Documents
2.1 ASTM Standards:
C859 Terminology Relating to Nuclear Materials
C998 Practice for Sampling Surface Soil for Radionuclides
C999 Practice for Soil Sample Preparation for the Determination of Radionuclides
C1163 Practice for Mounting Actinides for Alpha Spectrometry Using Neodymium Fluoride
D1193 Specification for Reagent Water
D3084 Practice for Alpha-Particle Spectrometry of Water
D3648 Practices for the Measurement of Radioactivity
3. Terminology
3.1 For definitions of terms in this standard, refer to Terminology C859.
3.1 Definitions:
This test method is under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods of Test.
Current edition approved June 1, 2012Dec. 1, 2020. Published June 2012February 2021. Originally approved in 1991. Last previous edition approved in 20072012 as
C1205C1205 – 07 (2012).–07. DOI: 10.1520/C1205-07R12.10.1520/C1205-20.
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’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C1205 − 20
3.1.1 Except as otherwise defined herein, definitions of terms are as given in Terminology C859.
4. Summary of Test Method
4.1 Americium–241Americium-241 is determined in prepared soil samples of up to 10 g. The soil is completely dissolved by use
of pyrosulfate fusion. After an initial separation on barium sulfate and extraction with an organophosphorous compound, the
americium is separated from the other trivalent actinides and the rare earths by oxidation of the americium and precipitation of the
interferences. The americium is prepared for alpha spectrometry by coprecipitation with neodymium fluoride and the
241 243
americium–241Am determined by alpha spectrometry using americium–243Am as a yield monitor.
4.2 Typical radiochemical recoveries of this test method as determined by the yield monitor, are between 75 and 90 %.
Decontamination factors from other radionuclides that may interfere with the determination of americium in this energy range are
4 5
10 –10 .
4.3 The reagent blank contains all reagents plus the americium–243Am tracer. Five samples and a reagent blank can be
completed and ready for alpha spectrometry in approximately 6 h. The full-width at half-maximum (FWHM) detector resolution
ranges between 43 and 65 keV.
5. Significance and Use
5.1 This test method provides the speed and high decontamination factors attainable with liquid-liquid extraction of the actinides
and eliminates filtration techniques that are more time consuming.
5.2 This test method provides a precise determination of americium in concentrations normally found in environmental samples.
6. Interferences
6.1 Plutonium, if inadequately separated, may interfere with the alpha spectrometric determination of americium–241.
Thorium–228,Am. Thorium-228, identifiable by its daughter products, progeny, is a serious interference to the final determination
of americium by alpha spectrometry if decontamination factors are not sufficiently high. An inadequate separation of
210 243
polonium–210Po may result in an inaccurate determination of the americium–243Am yield monitor but this is unlikely when
using the neodymium fluoride precipitation method. If high concentrations of these radionuclides are known to be present, a
preliminary separation may be required.
7. Apparatus
7.1 Alpha pulse height analysis system as in Practice D3084.
7.1.1 A system consisting of a silicon surface barrier detector capable of 50 keV or better resolution on standards electrodeposited
on a flat, mirror finished disk is required. Samples prepared for alpha spectrometry using neodymium fluoride mounting by Practice
C1163 should be capable of 60 to 70 keV resolution. The resolution is defined as the width of an alpha energy peak when the counts
on either side of the peak are equal to one-half of the counts at the maximum of the peak (FWHM).
7.1.2 The counting efficiency of the system (that is, count/disintegration) should be greater than 20 % and the instrument
background in the region of each energy peak used for analysis should be less than five counts in 60 000 s (1000 min).
7.2 Membrane Filter (such as cellulose nitrate or cellulose acetate), 47 mm diameter, 0.45 μm pore size.
7.3 Platinum dish, 250 mL.
7.4 Blast burner.
7.5 Ring stand.
7.6 Glass beaker, 800 mL.
C1205 − 20
7.7 Hot plate with fiberglass mat cover.
7.8 Erlenmeyer flask, 125 mL.
7.9 Separatory funnel, 60 mL.
7.10 Polycarbonate counting bottle, 70 mL.
7.11 Centrifuge.
7.12 Hot water bath.
7.13 Tetrafluoroethylene (TFE) fluorocarbon beaker.
7.14 Conical polycarbonate centrifuge tube, 50 mL.
7.15 Round bottom polycarbonate centrifuge tube, 50 mL.
7.16 Ice water bath.
8. Reagents and Materials
8.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where
such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high
purity to permit its use without lessening the accuracy of the determination.
8.2 Purity of Water—Unless otherwise indicated, reference to water shall be understood to mean reagent water as defined in
Specification D1193, Type III or better.
243 3 243
8.3 Americium Tracer—Purify the americium–243Am tracer. The americium–243Am tracer may be available from NIST
or other recognized standards laboratories.
8.4 Potassium Fluoride, anhydrous.
8.5 Potassium Sulfate, anhydrous.
8.6 Sodium Sulfate, anhydrous.
8.7 Ammonium Persulfate (ammonium peroxydisulfate).
8.8 Hydrochloric Acid (sp gr 1.19)—Concentrated hydrochloric acid (HCl).
8.9 Hydrofluoric Acid (sp gr 1.20)—Concentrated hydrofluoric acid (HF).
8.10 Sulfuric Acid (sp gr 1.84)—Concentrated sulfuric acid (H SO ).
2 4
8.11 Sulfuric Acid Solution 0.5 %—Mix 5 mL of concentrated sulfuric acid with water and dilute to one liter.1 L.
For a description of thethis process, see Sill, C. W., Anal. Chem.Analytical Chemistry, 46, 1974, pp. 1426–1431.
C1205 − 20
8.12 Nitric Acid (sp gr 1.42)—Concentrated nitric acid (HNO ).
8.13 Potassium Metabisulfite Solution 25 %—Dissolve 25 g 25 g of potassium metabisulfite in water and dilute to 100 mL.
8.14 Sodium Bromate Solution 10 %—Dissolve 10 g of sodium bromate in water and dilute to 100 mL.
8.15 HDEHP Solution 15 %—Dissolve 150 mL of bis(2–ethylhexyl)phosphoricbis(2-ethylhexyl)phosphoric acid in 850 mL of
n–heptane.n-heptane.
8.16 Barium Chloride Solution 0.5 %—Dissolve 0.5 g of barium chloride in water and dilute to 100 mL.
8.17 5M Nitric Acid—Mix 312 mL of concentrated nitric acid with water and dilute to one liter.1 L.
8.18 Silver Nitrate Solution 0.5 %—Dissolve 0.5 g of silver nitrate in water and dilute to 100 mL.
8.19 Lanthanum Carrier (5 mg La/mL)— Dissolve 1.17 g of lanthanum nitrate in 75 mL of 5M nitric acid and dilute to 100 mL
100 mL with water.
8.20 Phosphoric Acid (sp gr 1.83)—Concentrated phosphoric acid (H PO ).
3 4
8.21 0.2M Ammonium Persulfate—Dissolve 2.3 g of ammonium persulfate in water and dilute to 50 mL. Prepare daily.
8.22 6M Ammonium Fluoride—Dissolve 22.2 g of ammonium fluoride in water and dilute to 100 mL.
8.23 0.10M Ammonium Persulfate–3NPersulfate-3N Ammonium Fluoride—Mix 20 mL of 0.2M ammonium persulfate with 20 mL
20 mL of 6M ammonium fluoride. Prepare daily.
8.24 Hydrogen Peroxide Solution 30 %.
8.25 Perchloric Acid (sp gr 1.67)—Concentrated perchloric acid (HClO ).
8.26 Neodymium Carrier (10 mg Nd/mL)—Heat 25 mL of 12M hydrochloric acid and 1.17 g of neodymium oxide on a hot plate
until the neodymium oxide is in solution. Cool the solution and dilute to 100 mL with water.
8.27 Neodymium Carrier (0.5 mg Nd/mL)—Dilute 5 mL of the 10 mg Nd/mL neodymium carrier solution to 100 mL with water.
9. Sampling
9.1 Collect the sample in accordance with Practice C998.
9.2 Prepare the sample for analysis in accordance with Practice C999.
10. Hazards
10.1 In addition to other precautions, adequate laboratory facilities, such as perchloric acid fume hoods and controlled ventilation,
along with safe techniques must be used in this procedure. Extreme care should be exercised in using hydrofluoric acid and other
hot concentrated acids, particularly hot perchloric acid. Use of safety equipment, especially safety glasses and rubber gloves, is
recommended.
10.2 Hydrofluoric acid is a highly corrosive and toxic acid that can severely burn skin, eyes, and mucous membranes. Hydrofluoric
acid is similar to other acids in that the initial extent of a burn depends on the concentration, the temperature, and the duration of
C1205 − 20
contact with the acid. Hydrofluoric acid differs from other acids because the fluoride ion readily penetrates the skin, causing
destruction of deep tissue layers. Unlike other acids that are rapidly neutralized, hydrofluoric acid reactions with tissue may
continue for days if left untreated. Due to the serious consequences of hydrofluoric acid burns, prevention of exposure or injury
of personnel is the primary goal. Utilization of appropriate laboratory controls (hoods) and wearing adequate personel protective
equipment to protect from skin and eye contact Familiarization and compliance with the Safety Data Sheet is essential.
10.3 Perchloric acid is one of the strongest acids known. At room temperature, aqueous solutions up to 72 % do not have
significant oxidizing power, and the corrosive properties are very similar to other mineral acids. However, the oxidizing power
increases with concentration and temperature. Concentrated perchloric acid (72 %) heated above 150 °C is a strong oxidizer, and
reacts violently with organic material, which has resulted in devastating explosions in specific situations. Familiarization and
compliance with the Safety Data Sheet is essential.
11. Calibration and Standardization
11.1 If an americium–243Am solution traceable to a national standards body is not available for use as a tracer, standardize a
freshly prepared s
...