Designation:D3946–92(Reapproved1997)StandardTestMethodforEvaluatingtheBacteriaResistanceofWater-DilutableMetalworkingFluids1ThisstandardisissuedunderthefixeddesignationD3946;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversevaluatingrelativebioresistanceofaqueousmetalworkingfluidsbychallengingthemwithabiologicalinoculumpreparedfromspecificdeterioratedmet-alworkingfluidfromtheuser’ssite.1.2Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:E70TestMethodforpHofAqueousSolutionswiththeGlassElectrode2E686MethodforEvaluationofAntimicrobialAgentsinAqueousMetalworkingFluids33.SignificanceandUse3.1Thistestmethodisapplicablefordetermininginthelaboratorytheratingsoffluidsascompoundedfromfluidmanufacturersandfordeterminingtheneedforbiocideaddi-tionpriortoutilizationofthefluidsinworkingsystems.4.Apparatus4.1AirCompressor—Asuitableaircompressorusedtodelivercompressedairforstandardlaboratoryfunctionsshouldbeavailable.Forpurposesofthistestthesupplyofairshouldbecontinuousandsufficienttoaerate1Loffluidwithoutexcessivefoaming.4.2Incubator—Ideallyacabinetusedformaintainingtem-peraturesat3061°Cshouldbeused,butintheabsenceofsuchaninstrumentitisacceptabletoincubateatambientroomtemperatureoratthesametemperatureatwhichthetestsystemisrun.4.3Glassware:4.3.1FrenchSquareBottles,432oz(960mL),withcap.Onebottleisneededforeachtest.Thisstyleofbottleisusefulbecauseithasamaximumheight-to-surfacearearatioandwillmaximallyencourageanaerobicconditionsduringtheperfor-manceofthetest.4.3.2DilutionBottles—Containersareneededformakingappropriatedi...
