Designation:E1248−90(Reapproved2009)StandardPracticeforShredderExplosionProtection1ThisstandardisissuedunderthefixeddesignationE1248;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoversgeneralrecommendeddesignfea-turesandoperatingpracticesforshredderexplosionprotectioninresourcerecoveryplantsandotherrefuseprocessingfacili-ties.1.2Hammermillsandothertypesofsizereductionequip-ment(collectivelytermedshredders)areemployedatmanyfacilitiesthatmechanicallyprocesssolidwastesforresourcerecovery.Flammableorexplosivematerials(forexample,gases,vapors,powders,andcommercialandmilitaryexplo-sives)maybepresentintheas-receivedwastestream.Thereispotentialforthesematerialstobereleased,dispersed,andignitedwithinornearashredder.Therefore,explosionpreven-tionanddamageameliorationprovisionsarerequired.2.ReferencedDocuments2.1NationalFireProtectionAssociationStandards:NationalElectricalCodeNFPA13SprinklerSystemsNFPA68GuideforExplosionVentingNFPA69ExplosionPreventionSystemsNFPA497AClassificationofClassIHazardous(Classified)LocationsforElectricalInstallationsinChemicalProcessAreas3.Terminology3.1Definitions:3.1.1deflagration—anexplosioninwhichtheflameorreactionfrontpropagatesataspeedwellbelowthespeedofsoundintheunburnedmedium,suchthatthepressureisvirtuallyuniformthroughouttheenclosure(shredder)atanytimeduringtheexplosion.3.1.2detonation—anexplosioninwhichtheflameorreac-tionfrontpropagatesatasupersonicspeedintotheunburnedmedium,suchthatpressureincreasesoccurintheformofshockwaves.3.1.3explosion—arapidreleaseofenergy(usuallybymeansofcombustion)withacorrespondingpressurebuildupcapableofdamagingequipmentandbuildingstructures.3.1.4explosionventing—theprovisionofanopening(s)intheshredderenclosureandcontiguousenclosedareastoallowgasestoescapeduringadeflagrationan...
