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【英文标准名称】:StandardPracticeforBloodIrradiationDosimetry
【原文标准名称】:血液辐射剂量测定的标准实施规程
【标准号】:ASTMISO/ASTM51939-2005
【标准状态】:现行
【国别】:美国
【发布日期】:2005
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E10.01
【标准类型】:(ISO/ASTM)
【标准水平】:()
【中文主题词】:
【英文主题词】:absorbeddose;absorbed-dosemapping;bloodproducts;bloodirradiation;dosimeter;dosimetrysystem;irradiator;ionizingradiation;measurementqualityassuranceplan;measurementuncertainty;radiation-sensitiveindicators;reference-standarddosimeter
【摘要】:4.1Theassurancethatbloodandbloodcomponentshavebeenproperlyirradiatedisofcrucialimportanceforpatienthealth.Theirradiatoroperatormustdemonstratebymeansofaccurateabsorbed-dosemeasurementsontheproduct,orinsimulatedproduct,thatthespecifiedabsorbeddosehasbeenachievedthroughouttheproduct.4.2Bloodandbloodcomponentsareirradiatedatpredetermineddosestoinactivateviablelymphocytestohelppreventtransfusion-inducedgraft-versus-hostdisease(GVHD)incertainimmunocompromisedpatientsandthosereceivingrelated-donorproducts(1,2).64.3Bloodandbloodcomponentsmaybetreatedwithionizingradiation,suchasgammaraysfrom137Csor60Cosources,andfromself-containedX-ray(bremsstrahlung)unitsandmedicallinearX-ray(bremsstrahlung)andelectronacceleratorsusedprimarilyforradiotherapy.4.3.1Theterms"gammarays"and"gammaradiation"areusedinterchangeably,asaretheterms"X-ray"and"Xradiation."4.4Bloodirradiationspecificationsincludealowerlimitofabsorbeddose,andmayincludeanupperlimitorcentraltargetdose.Foragivenapplication,anyofthesevaluesmaybeprescribedbyregulationsthathavebeenestablishedonthebasisofavailablescientificdata.See2.4.4.5Foreachbloodirradiator,anabsorbed-doserateatareferencepositionwithinthecanisterismeasuredbythemanufactureraspartofacceptancetestingusingareferencestandarddosimetrysystem.Thatreference-standardmeasurementisusedtocalculatethetimersettingrequiredtodeliverthespecifiedabsorbeddosetothecenterofthecanisterwithbloodandbloodcomponents,orotherreferenceposition.Eitherrelativeorabsoluteabsorbed-dosemeasurementsareperformedwithintheblood-orblood-equivalentvolumefordeterminingtheabsorbed-dosedistribution.Accurateradiationdosimetryatareferencepositionwhichcouldbethepositionofthemaximumabsorbeddose(Dmax)orminimumabsorbeddose(Dmin)offersaquantitative,independentmethodtomonitortheradiationprocess.4.6Dosimetryispartofameasurementqualityassuranceprogramthatisappliedtoensurethattheradiationprocessmeetspredeterminedspecifications(3).4.7Absorbed-dosemappingisoftenperformedusingsimulatedproduct(forexample,polystyreneisconsideredbloodequivalentfor137Csphotonenergies).4.8Bloodandbloodcomponentsareusuallychilledorfrozen.Careshouldbetaken,therefore,toensurethatthedosimetersandradiation-sensitiveindicatorscanbeusedundersuchtemperatureconditions.4.9Properdocumentationandrecordkeepingarecriticalcomponentsofradiationprocessing.Thisstandarddoesnotaddressthisissuesincethepertinentgoverningbodiessetminimumrequirements.4.10Mostdosimetershavesignificantenergydependenceatphotonandelectronenergieslessthan100keV,sogreatcaremustbeexercisedwhenmeasuringabsorbeddoseinthatenergyrange.1.1Thispracticeoutlinesirradiatorinstallationqualification,operationalqualification,performancequalification,androutineproductprocessingdosimetricprocedurestobefollowedintheirradiationofbloodandbloodcomponentsbytheblood-bankingcommunity.Iffollowed,theseprocedureswillhelptoensurethattheproductsprocessedwithionizingradiationfromgamma,X-rays(bremsstrahlung),orelectronsourcesreceiveabsorbeddoseswithinapredeterminedrange.1.2Thispracticecoversdosimetryfortheirradiationofbloodforthesetypesofirradiators:self-containedirradiators(free-standingirradiators)utilizing137Cs,60CoorX-rays(bremsstrahlung),teletherapyunits,andelectronaccelerators.Theabsorbeddoserangeforbloodirradiationistypically15Gyto50Gy.Insomejurisdictions,theabsorbeddoserangeforbloodirradiationis25Gyto50Gy.1......
【中国标准分类号】:
【国际标准分类号】:
【页数】:12P.;A4
【正文语种】:英语