Designation:D6443−14(Reapproved2019)´1StandardTestMethodforDeterminationofCalcium,Chlorine,Copper,Magnesium,Phosphorus,Sulfur,andZincinUnusedLubricatingOilsandAdditivesbyWavelengthDispersiveX-rayFluorescenceSpectrometry(MathematicalCorrectionProcedure)1ThisstandardisissuedunderthefixeddesignationD6443;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ε1NOTE—Subsection7.5.2waseditoriallycorrectedinJuly2019.1.Scope1.1Thistestmethodcoversthedeterminationofcalcium,chlorine,copper,magnesium,phosphorus,sulfur,andzincinunusedlubricatingoils,additives,andadditivepackagesbywavelengthdispersiveX-rayfluorescencespectrometry.Ma-trixeffectsarehandledwithmathematicalcorrections.1.2Foreachelement,theupperlimitoftheconcentrationrangecoveredbythistestmethodisdefinedbythehighestconcentrationlistedinTable1.Samplescontaininghigherconcentrationscanbeanalyzedfollowingdilution.1.3Foreachelement,thelowerlimitoftheconcentrationrangecoveredbythistestmethodcanbeestimatedbythelimitofdetection(LOD)2(seealso40CFR136AppendixB)orlimitofquantification(LOQ),2bothofwhichcanbeestimatedfromSr,therepeatabilitystandarddeviation.LODandLOQvalues,determinedfromresultsobtainedintheinterlaboratorystudyonprecision,arelistedinTable2.1.3.1LODandLOQarenotintrinsicconstantsofthistestmethod.LODandLOQdependupontheprecisionattainablebyalaboratorywhenusingthistestmethod.1.4Thistestmethodusesregressionsoftwaretodeterminecalibrationparameters,whichcanincludeinfluencecoeffi-cients(thatis,interelementeffectcoefficients)(GuideE1361),hereinreferencedasalphas.Alphascanalsobedeterminedfromtheoryusingrelevantsoftware.1.5SetupofthistestmethodisintendedforpersonstrainedinthepracticeofX-rayspectrometry.Followingsetup,thistestmethodcanbeusedroutinely.1.6ThevaluesstatedineitherSIunitsorangstrom(Å)unitsaretoberegardedsepa...
