Designation:D5074−90(Reapproved2022)StandardPracticeforPreparationofNatural-MatrixSedimentReferenceSamplesforMajorandTraceInorganicConstituentsAnalysisbyPartialExtractionProcedures1ThisstandardisissuedunderthefixeddesignationD5074;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoversuniformprocedurestodevelop,select,collect,prepare,anduseoxidized,relativelyunpolluted,aquaticnatural-matrixbed-sedimentreferencesamplesforthecollaborativetestingofchemicalmethodsofanalysisforsedimentsandsimilarmaterials.Referencesamplespreparedusingthispracticeareintendedforuseasnaturalsediments,analyzableformajor,minor,andtraceelements,andgeneralphysical/organicanalysesonly.Thesamplesarenotdesignedortestedforenvironmentalpollutantssuchastraceorganiccompounds.1.2Few,ifany,aquaticsedimentreferencematerialshavebeencertified,defined,orareevenavailablefordevelopingorevaluatingpartialandsequentialextractionprocedures.Thispracticedescribesfactorsandconsiderationsinsiteselection,samplecharacteristics,collection,andsubsequentrawsampletreatmentneededtopreparenatural-matrixbed-materialsedi-mentsforuseaspartialorsequentialextractionprocedurereferencetestsamples.Theuserofthispracticeiscautionedthatinlightofthemanyvariablesthatmayaffectnaturalmaterials,neitherthelistoffactorsincludedforevaluationnorpreparationofnatural-matrixreferencesamplesshouldbeconsideredasallinclusive.Itistheuser’sresponsibilitytoensurethevalidityandapplicabilityofthesepracticesforpreparingspecific-matrixsamplesappropriatefortestingtheconstituentsofinterestandtheoperationallydefinedextractionproceduresutilized.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsu...
