Designation:E2564−13AnAmericanNationalStandardStandardPracticeforEnumerationofMycobacteriainMetalworkingFluidsbyDirectMicroscopicCounting(DMC)Method1ThisstandardisissuedunderthefixeddesignationE2564;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticedescribesadirectmicroscopiccountingmethod(DMC)fortheenumerationoftheacidfaststainedmycobacteriapopulationinmetalworkingfluids.Itcanbeusedtodetectlevelsoftotalmycobacteriapopulation,includingculturableaswellasnon-culturable(possiblydeadormori-bund)bacterialcells.Thispracticeisrecommendedforallwater-basedmetalworkingfluids.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Foradditionalsafetyinformation,seeLaboratorySafety:PrincipleandPractices,4thEdition22.ReferencedDocuments2.1ASTMStandards:3D2881ClassificationforMetalworkingFluidsandRelatedMaterials3.Terminology3.1DefinitionsofTermsSpecifictoThisStandard:3.1.1acid-fastbacteria,n—adistinctivestainingpropertyofMycobacteriaduetotheirlipid-richcellwalls.3.1.1.1Discussion—Oncestained,mycobacteriumresistde-colorizationwhenexposedtoacidifiedorganicsolvents,andaretherefore,informallydesignatedacid-fast.3.1.2non-tuberculousMycobacteria(NTM)—environmentalmycobacteria,notassociatedwithtuberculosis.3.1.3microscopicfactor(MF),n—acalibratedconversionfactorforcalculatingtheMycobacteriumcountpermLsample.3.1.3.1Discussion—Theaveragenumberofmycobacteriumcellsperonemicroscopicfield(oroilfield,OIF)ismultipliedbytheMFtogivetheconcentrationofmycobacteriumpermLofsample.3.1.4oilimmersionfield(OIF),n—thecircularareaofamicroscopicfieldvisibleintheeyepieceofthemicroscopeusing...
