Designation:D4557–85(Reapproved1995)StandardPracticeforCollectingBenthicMacroinvertebrateswithSurberandRelatedTypeSamplers1ThisstandardisissuedunderthefixeddesignationD4557;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoverstheproceduresforobtainingasampleofmacroinvertebratesinhabitingmud,sand,gravel,orrubblesubstrate.1.2Thedeviceisrestrictedtouseinshallowstreamsorshallowareasofrivers,anditdependsonawatervelocityofnotlessthan0.05m/stowashthesampleintoanet.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.Foraspecifichazardstatement,see6.8.2.ReferencedDocuments2.1ASTMStandards:D1129TerminologyRelatingtoWater2D4556GuideforSelectingStream-NetSamplingDevicesforCollectingBenthicMacroinvertebrates33.Terminology3.1Definitions:3.1.1Fordefinitionsoftermsusedinthispractice,seeTerminologyD1129.4.SummaryofPractice4.1TheSurbersamplerconsistsoftwo30.5-cmframes,hingedtogether;oneframerestsonthesubstrate,theotherremainsuprightandholdsthenylonnet.Thesamplerispositionedwithitsnetmouthopen,facingupstream.4.2Wheninuse,thetwoframesarelockedatrightangles,oneframemarkingofftheareaofsubstratetobesampledandtheotherframesupportinganettostrainoutorganismswashedintoitfromthesamplearea.4.3ModificationoftheSurbersamplertoovercomesomeofthelimitationsofitsuse(forexample,lossoforganismsduetobackwash)hasresultedinthedesignandconstructionofanumberofrelatedsamplingdevices,suchasthefour-sided(enclosed)portableinvertebrateboxsampler,thecylindricalHesssampler,thecylindricalHessstreambottomsampler,andthecylindricalstream-bedfaunasampler.4.4Operationoftheportableinvertebratebox,Hess,He...
