Designation:E1733−95(Reapproved2014)StandardGuideforUseofLightinginLaboratoryTesting1ThisstandardisissuedunderthefixeddesignationE1733;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Theuseofartificiallightingisoftenrequiredtostudytheresponsesoflivingorganismstocontaminantsinacon-trolledmanner.Evenifthetestorganismdoesnotrequirelight,theinvestigatorwillgenerallyneedlighttomanipulatethesamples,andthetestmightbeconductedundertheambientlightofthelaboratory.Onewillneedtoconsidernotonlywhethertheparticulartestorganismrequireslightforgrowth,butalsowhethertheenvironmentalcompartmentrelevanttothetestisexposedtolightand,ifso,whattheattributesoflightareinthatcompartment.Thelightcouldaffectgrowthoftheorganismortoxicityofacontaminant,orboth.Forinstance,ithasbeenshownthatthetoxicityofsomeorganicpollutantsisenhanceddramaticallybytheultraviolet(UV)radiationpresentinsunlight(1,2).2Furthermore,thelevelofambientlightinginthelaboratory(whichmightaffectthetest)isnotstandardized,norisitcomparabletonaturalenvironments.Itisthusimportanttoconsiderlightinginallformsofenvironmentaltesting.Whenlightisusedinthetest,oneshoulddeterminewhetherthespectraldistributionoftheradiationsourcemimicssunlightadequatelytobeconsideredenvironmentallyrelevant.Also,thecontainerorvesselfortheexperimentmustbetransparent,atthepointoflightentry,toallofthespectralregionsinthelightsourceneededforthetest.1.2Itispossibletosimulatesunlightwithrespecttothevisible:UVratiowithrelativelyinexpensiveequipment.Thisguidecontainsinformationonthetypesofartificiallightsourcesthatarecommonlyusedinthelaboratory,composi-tionsoflightsourcesthatmimicthebiologicallyrelevantspectralrangeofsunlight,quantificationofirradiancelevelsofthelightsources,determinationofspectraloutputsofthelightsources,transmittancepropertiesof...
