Designation:D8196−22StandardPracticeforDeterminationofWaterActivity(aw)inCannabisFlower1ThisstandardisissuedunderthefixeddesignationD8196;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.INTRODUCTIONTheconceptofwateractivityismorethan50yearsold.Formanyyears,researcherstriedtoequatebacterialgrowthpotentialwithwatercontent.WilliamJonesScottshowedin1953thatmicroorgan-ismshavealimitingawlevelforgrowth(1),2thusbeingthefirsttoestablishthatbacterialgrowthcorrelatedwithwateractivity,notwatercontentoforganicmaterials.Itisnowgenerallyacceptedthatawismorecloselyrelatedtothemicrobial,chemical,andphysicalpropertiesoffoodsandothernaturalproductsthanistotalmoisture(2).Itisfirmlyestablishedthatgrowthofspecificmicrobesisinhibitedatorbelowspecificwateractivityvalues(3).Totalwatercontent(moisture)measurementsdonotnecessarilyreflectwateravailableformicrobialgrowthandthusareaninaccuratemeansforcontrollingmicrobialgrowth,becausethewatercontentsufficientformicrobialgrowthisdependentonthesubstancebeingtested.Wateractivitymeasurementismoreaccuratethantotalwatercontent(moisture)measurementasitrelatesdirectlytothewateravailabletomicrobes.Safeawlevelsareconstantrelativetoparticularmicrobes,regardlessofthesubstancebeingtested.1.Scope1.1Thispracticecoverstherecommendedprocedurefordeterminingthewateractivity(aw)ofacannabisflowersample.1.2Units—ThevaluesstatedinSIunitsaretoberegardedasthestandard.Wateractivityisaratio,andthusiswithoutunitdesignation.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinci...
