Designation:C1279−13StandardTestMethodforNon-DestructivePhotoelasticMeasurementofEdgeandSurfaceStressesinAnnealed,Heat-Strengthened,andFullyTemperedFlatGlass1ThisstandardisissuedunderthefixeddesignationC1279;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationofedgestressesandsurfacestressesinannealed,heat-strengthened,andfullytemperedflatglassproducts.1.2Thistestmethodisnon-destructive.1.3Thistestmethodusestransmittedlightandis,therefore,applicabletolight-transmittingglasses.1.4Thetestmethodisnotapplicabletochemically-temperedglass.1.5Usingtheproceduredescribed,surfacestressescanbemeasuredonlyonthe“tin”sideoffloatglass.1.6Surface-stressmeasuringinstrumentsaredesignedforaspecificrangeofsurfaceindexofrefraction.1.7ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.8Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2C158TestMethodsforStrengthofGlassbyFlexure(De-terminationofModulusofRupture)C162TerminologyofGlassandGlassProductsC770TestMethodforMeasurementofGlassStress—OpticalCoefficientC1048SpecificationforHeat-StrengthenedandFullyTem-peredFlatGlassE691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethod2.2OtherDocuments:EngineeringStandardsManual3“SurfaceandEdgeStressinTemperedGlass”43.Terminology3.1Definitions:3.1.1analyzer—apolarizingelement,typicallypositionedbetweenthespecimenbeingevaluatedandtheviewer.3.1.2polarizer—anopticalassemblythattransmitslightvibratinginasingleplanardirection,typicallypositionedb...
