b'PlyAdhesionisconsideredoneoft hemoreimportantattrib utes ofaroofingsystem.Althoughnotreportedonbyt h eNBS,one ofthemanufacturershasbeeninvestigat ingtheeffectsofsuch variablesas: 1.typeoffelt 2.typeandamountofsurfacing 3.porosityoftheplysheets 4.moisturecontentofplysheets 5.temperatureoffelt 6.typeandtemperatureof moppingbitumen Ininitialtestsnosignificantdifferenceswerefoundbetween variousplysheetsinregardtobondingcapabilityproviding therewasadequateasphaltatpropertemperaturetogetgood wetting.Additionaltestingisunderway. WeatherResistance-Fieldexperienceisstillt hemostreliable practicalmethodyetdevisedtodetermi neweatherresistance. TheRSTCgrouphasenlistedthesupportofanumberofroofing contractorswhoagreetoapplysampleroofsystemseither on theirownbuildingsorbuildingsthatwillbereadilyavailable sothatsamplecutscanbetakenoninitialapplicationand afterspecifiedperiodsthereafterforanalysisandevaluation. Acompletedatafileisbeingmaintainedonthesetestroofs,a numberofwhichhavealreadybeeninstalledandevaluationbegun. UpliftResistance-Althoughit iswellknownthatFactoryMutual andUnderwritersLaboratorieshavehadlaboratoryupliftresistance testsavailableforanumberofyears,theneedforapractical fieldupliftresistancetesthasbeenrecognized.Twosuchtests arecurrentlybeingevaluated:theFMtwo-footsquaretripodtest andanon-destructivevacuumtest.Thelatterisgenerallyp r eferred. FireResistance-Ageneralconcensusofthegroupindicatedt he FMandU.L.testscurrentlyinuseprovideadequateratingsanddata. TensileandFlexuralFatigue-I tisnotyetknownwhetherthese twoattributesneedtobeconsideredindividuallyortogether. Verylittledataisavailableandit isdoubtfulthatother laboratoriescouldjustifythecostofequipmentutilizedinthe NBStests.OneoftheARMAmemberlaboratoriesispresentlyworkingtodevelopanothertest method. MoistureEffectsonStrengthandDimensionalChange-Oneofthe areasnotreportedonbyNBSist heeffectofm istureonthe ostrengthofroofingfeltsandmembranes.Considerableworkhas beendonewithintheARMAAdHocCommitteeonPerformanceTesting anddataforseveralfeltsandmembraneshasbeenobtained.A methodoftestfortheeffectofmoistureonthedimensionsof saturatedfeltswasalsodescribed. ThermalShockFactorisconsideredaperformanceindicator,but anacceptabletest methodhasnotbeenestablishedfort he expansion/contractionco-efficient.'