STM_51401-13.pdf

ISO/ASTM 51401:2013(E)Standard Practice forUse of a Dichromate Dosimetry System1This standard is issued under the fixed designation ISO/ASTM 51401;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.1.Scope1.1 This practice covers the preparation,testing,and proce-dure for using the acidic aqueous silver dichromate dosimetrysystem to measure absorbed dose to water when exposed toionizing radiation.The system consists of a dosimeter andappropriate analytical instrumentation.For simplicity,the sys-tem will be referred to as the dichromate system.The dichro-mate dosimeter is classified as a type I dosimeter on the basisof the effect of influence quantities.The dichromate systemmay be used as either a reference standard dosimetry system ora routine dosimetry system.1.2 This document is one of a set of standards that providesrecommendations for properly implementing dosimetry inradiation processing,and describes a means of achievingcompliance with the requirements of ISO/ASTM Practice52628 for the dichromate dosimetry system.It is intended to beread in conjunction with ISO/ASTM Practice 52628.1.3 This practice describes the spectrophotometric analysisprocedures for the dichromate system.1.4 This practice applies only to gamma radiation,X-radiation/bremsstrahlung,and high energy electrons.1.5 This practice applies provided the following conditionsare satisfied:1.5.1 The absorbed dose range is from 2 103to5 104Gy.1.5.2 The absorbed dose rate does not exceed 600 Gy/pulse(12.5 pulses per second),or does not exceed an equivalent doserate of 7.5 kGy/s from continuous sources(1).21.5.3 For radionuclide gamma sources,the initial photonenergy shall be greater than 0.6 MeV.For bremsstrahlungphotons,the initial energy of the electrons used to produce thebremsstrahlung photons shall be equal to or greater than 2MeV.For electron beams,the initial electron energy shall begreater than 8 MeV.NOTE1The lower energy limits given are appropriate for a cylindricaldosimeter ampoule of 12 mm diameter.Corrections for displacementeffects and dose gradient across the ampoule may be required for electronbeams(2).The dichromate system may be used at lower energies byemploying thinner(in the beam direction)dosimeter containers(see ICRUReport 35).1.5.4 The irradiation temperature of the dosimeter shall beabove 0C and should be below 80C.NOTE2The temperature coefficient of dosimeter response is knownonly in the range of 5 to 50C(see 5.2).Use outside this range requiresdetermination of the temperature coefficient.1.6 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.Specific precau-tionary statements are given in 9.3.2.Referenced documents2.1 ASTM Standards:3E170 Terminology Relating to Radiation Measurements andDosimetryE178 Practice for Dealing With Outlying ObservationsE275 Practice for Describing and Measuring Performance ofUltraviolet and Visible SpectrophotometersE666 Practice for Calculating Absorbed Dose From Gammaor X RadiationE668 Practice for Application of Thermoluminescence-Dosimetry(TLD)Systems for Determining AbsorbedDose in Radiation-Hardness Testing of Electronic DevicesE925 Practice for Monitoring the Calibration of Ultraviolet-Visible Spectrophotometers whose Spectral Bandwidthdoes not Exceed 2 nmE958 Practice for Estimation of the Spectral Bandwidth ofUltraviolet-Visible Spectrophotometers2.2 ISO/ASTM Standards:351261 Practice for Calibration of Routine Dosimetry Sys-tems for Radiation Processing51707 Guide for Estimating Uncertainties in Dosimetry forRadiation Processing1This practice is under the jurisdiction of ASTM Committee E61 on RadiationProcessing and is the direct responsibility of Subcommittee E61.02 on DosimetrySystems,and is also under the jurisdiction of ISO/TC 85/WG 3.Current edition approved Sept.14,2013.Published November 2013.Originallypublished asASTM E 1401 91.ASTM E 1401 961was adopted by ISO in 1998with the intermediate designation ISO 15561:1998(E).The present InternationalStandard ISO/ASTM 51401:2013(E)replaces ISO 15561 and is a major revision ofthe last previous edition ISO/ASTM 51401:2003(E).2The boldface numbers in parentheses refer to the bibliography at the end of thispractice.3For referenced ASTM and ISO/ASTM standards,visit the ASTM website,www.astm.org,or contact ASTM Customer Service at serviceastm.org.ForAnnual Book of ASTM Standards volume information,refer to the standardsDocument Summary page on the ASTM website.ISO/ASTM International 2015 All rights reserved1 52628 Practice for Dosimetry in Radiation Processing52701 Guide for Performance Characterization of Dosim-eters and Dosimetry Systems for Use in Radiation Pro-cessing2.3 ISO/IEC Standards:417025 General Requirements for