ASTM_C_1295_-_15.pdf

Designation:C129515Standard Test Method forGamma Energy Emission from Fission and Decay Productsin Uranium Hexafluoride and Uranyl Nitrate Solution1This standard is issued under the fixed designation C1295;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the measurement of gammaenergy emitted from fission products in uranium hexafluoride(UF6)and uranyl nitrate solution.This test method may also beused to measure the concentration of some uranium decayproducts.It is intended to provide a method for demonstratingcompliance with UF6specifications C787 and C996,uranylnitrate specification C788,and uranium ore concentrate speci-fication C967.1.2 The lower limit of detection is 5000 MeV Bq/kg(MeV/kg per second)of uranium and is the square root of thesum of the squares of the individual reporting limits of thenuclides to be measured.The limit of detection was determinedon a pure,aged natural uranium(ANU)solution.The value isdependent upon detector efficiency and background.1.3 The fission product nuclides to be measured are106Ru/106Rh,103Ru,137Cs,144Ce,144Pr,141Ce,95Zr,95Nb,and125Sb.Among the uranium decay product nuclides that may bemeasured is231Pa.Other gamma energy-emitting fission anduranium decay nuclides present in the spectrum at detectablelevels should be identified and quantified as required by thedata quality objectives.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2C761 Test Methods for Chemical,Mass Spectrometric,Spectrochemical,Nuclear,and Radiochemical Analysis ofUranium HexafluorideC787 Specification for Uranium Hexafluoride for Enrich-mentC788 Specification for Nuclear-Grade Uranyl Nitrate Solu-tion or CrystalsC859 Terminology Relating to Nuclear MaterialsC967 Specification for Uranium Ore ConcentrateC996 Specification for Uranium Hexafluoride Enriched toLess Than 5%235UC1022 Test Methods for Chemical and Atomic AbsorptionAnalysis of Uranium-Ore ConcentrateD3649 Practice for High-Resolution Gamma-Ray Spectrom-etry of WaterE181 Test Methods for Detector Calibration and Analysis ofRadionuclides3.Terminology3.1 Except as otherwise defined herein,definitions of termsare as given in Terminology C859.4.Summary of Test Method4.1 A solution of the uranium sample is counted on ahigh-resolution gamma-ray spectrometry system.The resultingspectrum is analyzed to determine the identity and activity ofthe gamma-ray-emitting radioactive fission and decay prod-ucts.The number of counts recorded from one or more of thepeaks identified with each fission nuclide is converted todisintegrations of that nuclide per second(Bq).The gamma-rayenergy for a fission nuclide is calculated by multiplying thenumber of disintegrations per second of the nuclide by the1This test method is under the jurisdiction ofASTM Committee C26 on NuclearFuel Cycle and is the direct responsibility of Subcommittee C26.05 on Methods ofTest.Current edition approved June 1,2015.Published July 2015.Originally approvedin 1995.Last previous edition approved in 2014 as C1295 14.DOI:10.1520/C1295-15.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 mean gamma-ray energy emission rate of the nuclide.Thecalculated gamma-ray energy emission rates for all observedfission nuclides are summed,then divided by the mass of theuranium in the sample to calculate the overall rate of gammaenergy production in units of million electron volts per secondper kilogram of uranium.Decay product nuclides such as231Pawill be separately quantified and reported based on specificneeds.5.Significance and Use5.1 Specific gamma-ray emitting radionuclides in UF6areidentified and quantified using a high-resolution gamma-rayenergy analysis system,which includes a high-resolutiongermanium detector.This test method shall be used to meet thehealth and safety specifications of C787,C788,and C996regarding applicable fission products in reprocessed uraniumsolutions.This test method may also be used to provideinformation to parties such as conversion facilities on the levelof uranium decay products in such materials.Pa-231 is aspecific