b'echnicalandRes e archUp d a te Field Uplift Tests and FMLoss Prevention Sheet1-52 Kurt Baumgartner, Technical Advisor This is basically ain which awater. As the level of water in the test dome of some type isto thetubethe pressure is indisealedchanges roof, andnegative p iscated by aon the side of the thenressurescale e.heegatappliedtotheroof surfaceinsidetub T n ivepressureis thedometoduplicatetheupliftappliedinincremen often ts effect of wind on thefpou ruare foot and is hroo assembly.nds pe sq eld AlthoughMR throughtheat eachincreme for one minu . CA,ntteefforts of P lrris,JohnsonT scaleicates the corresponau Mo Rayheindando ers,originally developedding FM u ift c 1th pl ategories from-60 MRCAevice the d toprovidedefenseforto 1-180. opposesAfterrm losses in recent yearsroofingcontractors withblow-offIf at any time the upward de sto flecthe use offromhurricane Andrewto hurri damage, it is now the p tionoftion asme uredbythedevice upliftosi asca Katrinaa Rita,F ryMRCA toop theuseof theexceedsonequ inchfor the nesndacto posearter domes by FMtestMutual (FM)been requiring thedevicebyFMforthetestingofcategorybeingtested, thetest is tohas constructeduse of what has be kn asnewly constructed roof.deemed a comeownassemblies failure. newly the\'bubble test\'outlinedin FMTestsd rec tocomplyEngin ingcalculationsbased oneentlyeerroof assemblies.LossPrevention D a1 .with FM1-52haveexperiencedon 22-gage metal deck of three rib at Sheet-52fa ure rates as highnty types, widetypeB,intermediate il as seve percent.There are reasons for th type Fna typeindicate eseandrrowA, high f re,luding assem that deflection ofthedeckalo~ ailu rates incblyilure, but theiafailu could.18 of one inch att _) fa criter forreexceed theed in1-52 document is not bas PSF leaving only .07 of oneinch ons ndengineeringin thatitmargin fortheroofassembly to oudoes not take into consideration thepass the test. deflectionthe metal deck.De ectionofthedeckalso offlWhen thetestwasoriginallyincre with the weightof the ases conceived by Morris and Johnson,personsthefting the onroo conducit allowed fora deflectionof thetest.Thissmallmar isnot gin assembly ofinch.TMenough top aa le oneAS Stan ex ectre sonab and dard E-907, which iser ver accurate test result. anothsion of the bubble test, allows for aDeflectionis alsoimpacted by deflectionof onein andalsowhere the device is placed. If it is ch cal Is for furtherto determineplaced over ajoist the outcome testingbar the exact c of failure.will be different than if it is placed ause describe1- teLet methe FM52stbetweenthebarjoists.Furtherin detail, asasd ice. Themore, theseresultspresume the welltheevtest ch (see pho aproper attach ofmetal damberto) isdomementtheeck five feet byve feet. Itbe oneto the supporting steel structure. If fi may V LightweightvTo Transportp or assembledfrom pa . Atheis n properly a it Easyiecerts deckotttached measuring device is placed on thecouldassumed that deck d beeflecvvroofrface underd inetion mig evengr teOSHA ComRliantAffordablesu theometh htbeea r. exa center.N p isFor roofing contractors involved ctegativeressure v.To InstallvOver & over!th applied by pulling aminuc contractsq ring QuickUseenvacuu constr tionre uiinsidethed . Theamount ofthe u of this test, MRCA recomome se II C 763-694-262~negativereismends th theroofingcontractor GARLOCKMpressu appliedmeas at ured by the use of ater that wwguard.netmanomeeaemail:arlockequip.comis ash clear tu filled withntCo inued on next pai,_ "u"apedbe'