STM_52628-13.pdf

ISO/ASTM 52628:2013(E)An American National StandardStandard Practice forDosimetry in Radiation Processing1This standard is issued under the fixed designation ISO/ASTM 52628;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.INTRODUCTIONThe use of ionizing radiation for the treatment of commercial products such as the sterilization ofmedical devices,the reduction of microbial contamination in food or the modification of polymers isreferred to as radiation processing.The types of radiation used may be gamma radiation(typicallyfrom cobalt-60 sources),X-radiation or accelerated electrons.It is necessary to ensure that the specified absorbed dose is applied in each of the radiationprocessing applications.The absorbed dose must be measured,and measurement systems have beendeveloped for this purpose.Much of the development of these systems rests on the early developmentof dosimetry systems for personnel radiation protection and for medical treatment.However,theabsorbed doses used in radiation processing are generally higher,ranging from 10 Gy up to 100 kGyor more and new dosimetry systems have been developed for measurements of these doses.Note that the terms“dose”and“absorbed dose”are used interchangeably in this standard(see3.1.1).The dose measurements required in radiation processing concern characterization of radiationfacilities in installation qualification(IQ)and operational qualification(OQ),measurement of dosedistribution in irradiated products in performance qualification(PQ)and routine monitoring of theirradiation process.The literature is abundant with articles on dosimeters for radiation processing,and guidelines andstandards have been written by several organizations(the International Atomic Energy Agency(IAEA)and the International Commission on Radiation Units and Measurements(ICRU),forexample)for the operation of the dosimetry systems and for their use in the characterization andvalidation of the radiation processing applications.In particular,ICRU Report 80 provides informationon the scientific basis and historical development of many of the systems in current use.ASTM Subcommittee E10.01 on Radiation Processing:Dosimetry and Applications was formed in1984 initially with the scope of developing standards for food irradiation,but its scope was widenedto include all radiation processing applications.The subcommittee,now Committee E61,has under itsjurisdiction approximately 30 standard practices and standard guides,collectively known as the E61standards on radiation processing.A number of these standards have been published as ISO/ASTMstandards,thereby ensuring a wider international acceptance.These practices and guides describe thedosimetry systems most commonly used in radiation processing,and the dose measurements that arerequired in the validation and routine monitoring of the radiation processes.A current list of the E61standards on radiation processing is given in 2.1 and 2.2.The development,validation and routine control of a radiation process comprises a number ofactivities,most of which rely on the ability to measure the delivered dose accurately.It is thereforenecessary that dose is measured with traceability to national,or international,standards,and theuncertainty is known,including the effect of influence quantities.The E61 standards on radiationprocessing dosimetry serve to fulfill these requirements.The practices describing dosimetry systems have several common attributes,and there is a need tohave one general standard that can act as a common reference and that can be used as a basis for theselection of dosimetry systems for defined tasks.ISO/ASTM Practice 52628 serves this purpose.Itoutlines general requirements for the calibration and use of dosimetry systems and for the estimationof measurement uncertainties.Details relating to each dosimetry system are found in the respectivestandards and each of these refer to ISO/ASTM Practice 52628 for the general requirements.ISO/ASTM International 2013 All rights reserved1 1.Scope1.1 This practice describes the basic requirements that applywhen making absorbed dose measurements in accordance withthe ASTM E61 series of dosimetry standards.In addition,itprovides guidance on the selection of dosimetry systems anddirects the user to other standards that provide specific infor-mation on individual dosimetry systems,calibration methods,uncertainty estimation and radiation processing applications.1.2 This practice applies to dosimetry for radiation process-ing applications using electrons or photons(gamma-orX-radiation).1.3 This practice addresses the minimum requirements of ameasurement management system,but does not include generalquality system requirements.1.4 This practice does not address personnel dosimetry ormedical dosimetry.1.5 This practice does not apply to primary standard dosim-etry systems.1.6 This standard does not purport to address all of thes