Designation:D4345–84(Reapproved1998)StandardPracticeforCollectingBenthicMacroinvertebrateswithVanVeenGrabSampler1ThisstandardisissuedunderthefixeddesignationD4345;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thispracticecoverstheproceduresforobtainingquali-tativeorquantitativesamplesofmacroinvertebratesinhabitingsand,clay,mud,gravel,andsimilarsubstrates.1.2Thisdeviceisusedinmarineandestuarinewatersandisadaptableforlargerivers.1.3Foradvantagesandlimitationsforgrabsamplingde-vices,seeGuideD4387.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityorregulatorylimitationspriortouse.Forspecifichazards,seeSection5.2.ReferencedDocuments2.1ASTMStandards:D4387GuideforSelectingGrabSamplingDevicesforCollectingBenthicMacroinvertebrates23.SummaryofPractice3.1TheVanVeengrabsamplerhaspairedjawsthatmustpenetratetheintendedsubstratewithoutdisturbingthewatersurfaceboundaryofthesubstrate,closebypincher-likeactionoftwolongarmswhenpositionedproperlyonthebottom,andretaindiscretesamplesofsedimentwhileitisbroughttothesurfaceforprocessing.3.2TheVanVeenisbasicallyanimprovedversionofthePetersengrabinthatlongarmshavebeenattachedtothejawstostabilizethegrabonthebottomintheopenseajustpriororduringclosingthedevice.3.3Additionalweightscanbeappliedtothejawstoeffectgreaterpenetrationinsediments.3.4Thelongarmsgiveaddedleverageforpenetratinghardsediments.3.5Largerversionsofthisgrabcanbeconstructeddepend-inguponthetypeofbottomtobesampled,andthetypeofvesselavailabletodeploythissampler.4.SignificanceandUse4.1TheVanVeengrabsamplerisusedtocollectqualitativeandquantitativesamplesfromdifferentaquatichabitatscon-tainingbenthicmacroinvert...
