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22RoadwayLightingFixedlightingofpublicwaysforbothvehiclesandpedestrianscancreateanighttimeenvironmentinwhichpeoplecanseecomfortablyandcanquicklyandaccuratelyidentifyobjectsontheroadwaybeingtraveled.Roadwaylightingcanimprovetrafficsafety,achieveefficienttrafficmovement,andpromotethegeneraluseofthefacilityduringdarknessandunderawidevarietyofweatherconditions.Asasupplementtovehicularheadlightillumination,fixedlightingcanenablethemotoristtoseedetailsmoredistinctly,locatethemwithgreatercertainty,andreactsafelytoroadwayandtrafficconditionspresentonorneartheroadwayfacility.Pedestriansmustbeabletoseewithsufficientdetailtoreadilynegotiatethepedestrianfacilityandrecognizethepresenceofotherpedestrians,vehicles,andobjectsintheirvicinity.Whenfixed-lightingprinciplesandtechniquesareproperlyapplied,thevisibilityprovidedonthesepublicwayscanprovideeconomicandsocialbenefitstothepublic,including:�Reductioninnighttimeaccidents�Aidtopoliceprotection�Facilitationoftrafficflow�Promotionofbusinessandindustryduringnighttimehours�InspirationforcommunityspiritandgrowthThischapterconsidersonlyfixedlightingforthedifferentkindsofpublicroads,pedestrianwalkwaysandbikewaysofaqualityconsideredappropriatetomodernrequirementsfornightuse.SeeChapter23,TransportationLighting,forinformationonvehicleheadlighting.CLASSIFICATIONDEFINITIONS1Roadway:PedestrianWalkwayandBikewayClassificationsFreeway.Adividedmajorroadwaywithfullcontrolofaccessandwithnocrossingsatgrade.Thisdefinitionappliestotollaswellasnontollroadsasfollows:FreewayA.Roadwayswithvisualcomplexityandhightrafficvolumes.Usuallythistypeoffreewayisfoundinmajormetropolitanareasinornearthecentralcoreandoperatesthroughmuchoftheearlyeveninghoursofdarknessatorneardesigncapacity.FreewayB.Allotherdividedroadwayswithfullcontrolofaccesswherelightingisneeded.Expressway.Adividedmajorroadwayforthroughtrafficwithpartialcontrolofaccessandgenerallywithinterchangesatmajorcrossroads.Expresswaysfornoncommercialtrafficwithinparkareasaregenerallyknownasparkways.Major.Thepartoftheroadwaysystemthatservesastheprincipalnetworkforthroughtrafficflow.Theroutesconnectareasofprincipaltrafficgenerationandimportantruralhighwaysenteringthecity.Collector.Theroadwaysservingtrafficbetweenmajorandlocalroadways.Theseareroadwaysusedmainlyfortrafficmovementswithinresidential,commercial,andindustrialareas.Local.Roadwaysusedprimarilyfordirectaccesstoresidential,commercial,industrial,orotherabuttingproperty.Theydonotincluderoadwayscarryingthroughtraffic.Longlocalroadwaysaregenerallydividedintoshortsectionsbyasystemofcollectorroadwaysystems.Alley.Narrowpublicwayswithinablock,generallyusedforvehicularaccesstotherearofabuttingproperties.Sidewalk.Pavedorotherwiseimprovedareasforpedestrianuse,locatedwithinpublicstreetrights-of-waythatalsocontainroadwaysforvehiculartraffic.PedestrianWalkway.Apublicwalkforpedestriantraffic,notnecessarilywithintheright-of-wayforavehiculartrafficroadway.Includedareskywalks(pedestrianoverpasses),subwalks(pedestriantunnels),walkwaysgivingaccesstoparksorblockinteriors,andmidblockstreetcrossings.IsolatedInterchange.Agrade-separatedroadwaycrossingthatisnotpartofacontinuouslylightedsystem,withoneormorerampconnectionswiththecrossroad.IsolatedIntersection.Thegeneralareawheretwoormorediscontinuouslylightedroadwaysjoinorcrossatthesamelevel.Theintersectionincludestheroadwayandro...