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DOCK PLANNING STANDARDSDOCKPLANNINGSTANDARDS 2013 Nova Technology InternationalAll Rights ReservedA

TABLE OF CONTENTSTABLE OF CONTENTSDESIGN THE SITE.2Safety.2Location of the Loading Docks.2Plan On-site Traffic Patterns.3Design the Apron Space.3Dock Approach.4Select the Loading Dock Configuration.5Inside/Outside Dock.6Open Dock.6Additional Dock Configurations.7Determine the Number of Dock Positions.8DESIGN THE LOADING DOCK.8Truck Specifications.8Sea Containers. 10Underride Protection Bars. 10Set the Dock Height. 10Set the Loading Bay Widths. 11Select Dock Doors. 12Determine Door Sizes. 12Widths. 12Heights. 13Design the Dock Interior. 13DOCKLEVELERS. 14Recessed Docklevelers. 14Mechanical Docklevelers. 15Powered Docklevelers. 15Edge-of-Dock Docklevelers. 16Specify the Correct Dockleveler. 17Length. 17Width. 18Lip Projection. 19Load Capacity. 19Activation System. 20Environmental Capability. 20Optional Features. 20Benefits of Hydraulic and Air Bag Docklevelers over Mechanical Docklevelers. 20Specifying the Elevating Dock. 21BUMPERS. 21TRAILER RESTRAINTS. 22RIG-Dependent Restraints. 23Manual Wheel Chocks. 23COMMUNICATION LIGHTS. 24DOCK RUN-OFF PROTECTION. 24Gate Barriers. 24Lip Barriers. 24SEALING SYSTEMS. 25Selection Criteria . 25Grade of Approach. 25Overhead Door Dimensions. 25Dock Bumper Projection. 26Dock Height. 26Mounting Surface. 26Compression Foam Dock Seals. 26Truck Shelters. 27Dock Lights. 28CONTACT NOVA. 28 2013 Nova Technology InternationalAll Rights Reserved1

DOCK PLANNING STANDARDSDESIGN THE SITESafetyThe Material Transfer Zone (MTZ), which acts asa bridge between the truck and warehouse, is adangerous place where safety must be the mostimportant consideration.Shipping docks and receiving docks can be combined,with shipping and receiving together (Figure 1), orthey can be separated, with shipping and receiving indifferent areas of the building (Figure 2).TrucksSafety is often considered only after a serious accidenthas occurred on the dock. To ensure the safety of dockattendants and product, consider all potential problemsthat could occur.Shipping andReceiving DockConsider security. Select the correct dock leveler foryour facility. For additional safety at the loading dock,consider adding a vehicle restraint to help preventunexpected trailer creep during the loading andunloading process.Perform regular maintenance on the equipment.Equipment should be cleaned, lubricated and checkedby a technician for longer product life and betterproductivity. Plan for maintenance of bumpers, lights,communication packages, and other loading dockaccessories. Inventory these items regularly as wheelchocks can be swept away by plows and light bulbswill need to be replaced. Perform regular checks onthe seals and shelters to make sure they do not leak.Infiltrating air will raise energy usage and may result inuncomfortable working conditions.Protect your investment. Choose a barrier gate thatprevents loading equipment from colliding with anddamaging the dock doors. A barrier gate acts as aprotective barrier against costly door damage.ManufacturingProcessFigure 1TrucksIntegrated control panels are useful when combiningdock and overhead doors with other loadingequipment. If you have combined a dockleveler with atrailer restraint and an automatic door, interconnectingeach into a single control panel is an effective way tocreate a safer work environment.Receiving DockSelect the appropriate dockleveler capacity basedon both the gross load and frequency of materialhandling devices in use at the site for optimal durabilityand safety. Also consider push button controlledpowered docklevelers for ergonomic and ease ofoperation reasons as they put less physical stresson the dock attendants. If non-powered mechanicaldocklevelers are already present, consider upgradingthe dockleveler to a push button controlled powereddockleveler with a hydraulic conversion kit.ManufacturingProcessShipping DockLocation of the Loading DocksLocate the loading docks to minimize forklift trafficinside the building. Rather than transporting individualpallets inside the building, unload trucks at multipledocks.TrucksFigure 22 2013 Nova Technology InternationalAll Rights Reserved

DOCK PLANNING STANDARDSChoose the loading dock location based on the needsof the in-plant process. A combined dock works wellin smaller buildings where shipping and receiving isinfrequent. However, this design may increase in-planttraffic and travel distance.A separated dock works well in buildings where thematerials enter production in one part of the buildingand the production is completed elsewhere. Thisdesign minimizes transportation of materials inside thebuilding. Two-way access roads that are 26 ft wide minimum(Figure 4)FacilityEntrancePlan On-site Traffic Patterns26 ft Min.RadiusDesign the traffic patterns around the building so thatthe truck driver is on the inside of each turn, for bestcontrol of the truck. Where traffic is on the right side ofthe road and the driver’s seat is on the left side of thecab, truck movement around the building should becounterclockwise (Figure 3).26 ftFigure 4 Separate roads for employee traffic Truck waiting areas near the loading docks toaccommodate all waiting trucksBuildingDesign the Apron SpaceApron space is the space between the loading platformand the nearest obstruction. Apron space includes theparking area where the truck parks at the dock and themaneuvering area, which is the area the truck uses tomaneuver in and out of the parking area (Figure 5) and(Figure 6). The recommended center distance betweendock positions is 12 ft minimum.Apron SpaceFigure 3Maneuvering AreaLoading PlatformParking AreaFor efficient truck traffic, plan for the following: An entrance driveway that accommodates theturning radius of the longest truck expected andallows trucks to be driven forward onto the site,rather than backed up Right-angle turns onto the site that have a minimuminside radius of 26 ft and a minimum outside radiusof 50 ft (Figure 4)Figure 5 One-way access roads that are 13 ft wide minimum(Figure 4) 2013 Nova Technology InternationalAll Rights Reserved3

DOCK PLANNING STANDARDS33 ft for40 ft ContainerApron SpaceManeuvering AreaLoading AreaLanding Gear PadFigure 7Dock Approach12 ft Min.Figure 6The minimum apron space required depends on the: Center line distances between the parked trucks atthe dock Length of the trucks Steering geometry of the trucksLess apron space is needed if the trailers will beparked with the tractors detached.The minimum apron space for a typical 40 ft containerrig is listed in Table 1.The maximum grade percentage from the loadingdock to the vehicle is determined by the height of thedock (discussed in detail in Set the Dock Height onpage 10). When using electric powered loadingequipment, the maximum grade percentage is 10%.For gas or diesel powered loading equipment themaximum grade percentage is 15%. If these gradepercentages are exceeded, damage to handlingequipment and load spillage may result.If the plant floor is at grade, or has a low grade,recess the truck parking area so that the trailer bedwill be at about the same height as the plant floor(Figure 8). The parking area will slope down towardthe dock. This slope should be 6% or less. If heavyloads are expected, the slope should not exceed 5%.If necessary, slope may be increased to an absolutemaximum of 10%, and only for light loads. Steepslopes may cause loads to topple.Table 1Center DistanceApron Space12 ft 13 ft 14 ft 16 ft 18 ft120 ft 116 ft 113 ft 110 ft 108 ftIf expected trucks are longer than 40 ft, increase theapron space proportionately. For example, if the dockcan accommodate 48 ft trailers, increase the apronspace in the table by 20%. If the traffic pattern causesthe driver to be on the outside of a turn, add 50 ft.Always provide a concrete landing gear pad to supportthe trailer’s landing gear when the trailer is detached(Figure 7). The landing gear is about 33 ft from theback of the trailer on a standard 40 ft containerchassis. The gear is about 11 ft from the back of thetrailer on a 20 ft chassis. The pad should be wideenough to accommodate all expected types of trailers.It is helpful for the pad to extend all the way back tothe loading platform. The pad should be designed tosupport two point loads of 25,000 lb each, 6 ft apart, tosupport a fully loaded trailer.4Figure 8Always provide drainage for recessed parking areas.The area next to the building should slope slightlyaway from the building for a short distance of 1 to 3 ft(Figure 9). A short distance is preferable so that theposition of the trailer’s rear axle will have less of aneffect on the height of the trailer bed at the dock. 2013 Nova Technology InternationalAll Rights Reserved

DOCK PLANNING STANDARDSDock HeightDrivewayGradeDrain1 to 3 ft1/2 to 1 in.Figure 9BuiltOutBlocksDrawbacks of a declined dock approach include thefollowing: Difficult removal of snowFigure 11 Drainage of water Debris buildup High impact forces to the building wall and dockWhen a declined dock approach is used, give specialattention to other loading equipment. Dock seals mustbe tapered to match the angle of the trailer. If the sealsare not tapered, sealing will not be effective and theseal may be damaged. Truck restraints must also beprojected sufficiently to ensure proper operation andsafety.Preventing dock approach impact is easily done.For new constructions, project the dock sufficientlyto prevent the top of the trailer from impacting thebuilding wall. When reconstructing an existing facilitywhere it is not possible to project the dock, project thebumpers by using bumper block outs.Area of ImpactThe required projection is calculated based on thegrade percentage. To calculate the grade, determinethe difference in height between the dock and a fixedpoint approximately 50 ft directly out from the dock.Grade equals the height difference divided by thelength measured.Example: 22 in. difference over 660 in. distance22 660 0.030.03 100 3% gradeFor proper dock operation, declined dock approachesshould be no more than 10%.Use Table 2 to determine the proper projection.Table 2Percent ofDrivewayGradePit Projection0%1%2%3%4%5% 10%0 in. 2 in. 3 in. 4 in. 5 in. 6 in. 12 in.Select the Loading Dock ConfigurationImportant factors in dock configuration include: Security Traffic control Safety Worker comfort Space availability ClimateFigure 10 2013 Nova Technology InternationalAll Rights ReservedThe two main types of dock configurations are theinside/outside dock and the open dock.5

DOCK PLANNING STANDARDSInside/Outside DockIn an inside/outside dock configuration, the loadingplatform is inside the building (Figure 12). With theproper door sealing system, an inside/outside dockprovides excellent weather protection and security. Therefrigerated dock is a common version of the inside/outside dock.SealCold RoomVestibuleDock DoorHigh-speedDoorInsulated DoorDocklevelerFigure 14Figure 12The inside/outside dock design may require thebuilding wall to be set back from the edge of the dock(Figure 13), especially for docks with recessed parkingareas. The setback works to: Protect the building wall from impact damage Protect projections, such as overhangs or signsOpen DockIn an open dock configuration, the loading platformis outside the building (Figure 15). Open docks arecommon in temperate climates. Adding a canopyover the loading platform and curtains aroundthe dock perimeter (Figure 16) will provide someprotection. When placing canopies over docks onsloped approaches, the height of the canopy mustaccommodate the height of the sloped truck. Facilitate the installation of sealing systems Minimize injury hazardsClearance is required between the truck and thebuilding wall. Allow for at least 6 in. of clearancebetween the rear of the truck and the building wall,measured at 6 ft above the dock platform. Allow a4 in. minimum clearance between the top of the trailerand the building wall (Figure 13).Figure 15Canopy4 in. Min.Slide Curtain6 in. Min. at 6 ftAbove DockDockleveler6 in. Min.Figure 16Figure 13Refrigerated docks require a vestibule between theplatform and refrigerated area. The vestibule createsan air lock between the outside and the refrigeratedarea (Figure 14), which will minimize the inflow ofwarm air. A carefully designed refrigerated dock willgreatly reduce energy usage.6An open dock requires sufficient maneuvering spacefor forklifts between building wall and the docklevelers.Safety barriers such as concrete posts or chains arenecessary to reduce the risk of forklifts driving off thedock (Figure 17). 2013 Nova Technology InternationalAll Rights Reserved

DOCK PLANNING STANDARDSTable 3Concrete PostsChainsFigure 17Additional Dock ConfigurationsBuilding and property limitations may require othertypes of loading docks.Saw-Tooth DockA saw-tooth design requires less apron space than aninside/outside or open dock (Figure 18).Saw-Tooth AngleCenterDistance15 30 45 60 12 ft121 ft106 ft88 ft67 ft13 ft119 ft105 ft86 ft66 ft14 ft118 ft103 ft85 ft65 ft15 ft116 ft102 ft84 ft64 ft16 ft114 ft101 ft83 ft63 ft17 ft113 ft99 ft82 ft63 ft18 ft112 ft98 ft81 ft62 ft19 ft111 ft97 ft80 ft62 ftIf smaller trucks will use the dock, decrease apronspace proportionately. If tractors will be detached fromthe trailers, decrease the required apron space shownin the table by 24 ft, 22 ft, 18 ft, and 14 ft for 15 , 30 ,45 , and 60 angles respectively.Example: If the center distance between the dockpositions is 17 ft and the saw tooth angle is 30 , therequired apron space is 99 ft minus 22 ft, or 77 ft.Pier DockIf dock positions cannot be placed along the buildingperimeter, a loading dock pier can be used (Figure 19).Angleof SawToothApronSpaceBuilding WallDockPierCenter Line of TrailersFigure 18Table 3 shows the required amount of apron space asdependent on center distance and saw tooth angle.The table is based on a 53 ft trailer with the tractorattached during loading. 2013 Nova Technology InternationalAll Rights ReservedDocklevelersFigure 197

DOCK PLANNING STANDARDSSelf-Standing DockIf space inside the building does not permit a loadingplatform, a self-standing dock structure can be addedoutside the building (Figure 20).Determine the Number of DockPositionsTo determine the required number of dock positions,obtain: Number of trucks to be served Average time to load or unload each truck Timing of each truck arrival and departureDock HouseDock SealConsider peak periods of use when determining thenumber of dock positions. Peak periods of use can bedaily, weekly, monthly, seasonally or yearly.NNOTE:Use the following formula to determine the number ofrequired dock positions. For the example, we will use36 trucks served in an 8-hour period (4.5 trucks perhour) with an average turnaround time of 45 minutes(0.75 hours) per truck. Turnaround time includesparking, loading and leaving.Building WallDocklevelerFigure 20Flush DockThe face of a flush dock is flush with the buildingsoutside wall. To prevent wall damage and protect dockseals on a level approach, project the foundation orbumper 4 in. beyond the outside wall. If the buildingwall extends beyond the face of the dock, addadditional foundation or bumper projection.Enclosed DockUse an enclosed dock when climate control, freightprotection, security, and overhead lift are required.Enclosed docks involve high construction expensesand consideration of vehicle exhaust pollution.Depressed DockUse a depressed dock with a sloped approach wherethe facility construction does not allow basementsand floors at the dock level. Plan the driveway gradecautiously. To avoid the top of the truck hitting thebuilding wall, cargo toppling, or pull-away tractionproblems resulting from ice or snow, do not allow thegrade to exceed 10%.8Consider providing one dock position for trashcollection.Number of Trucks per Hour Turnaround Time perTruck Number of Dock Positions4.5 Trucks per Hour 0.75 Hours 3.375 DockPositionsIn the example, 3.375 dock positions were calculated;therefore, 4 dock positions are required.If all the trucks arrive within a peak period of 4 hours,6.75, or 7, dock positions would be required.NNOTE:If the number of required dock positionscannot be provided, consider providing a truckwaiting area.DESIGN THE LOADING DOCKTo design efficient loading docks, determine the: Types and numbers of trucks that will use the docks Dimensions of the loading docks and doors Characteristics of the facility processesThen, consider the dock height, loading bay width, anddimensions and layout of the building interior.Truck SpecificationsDetermine the types and dimensions of the trucksthat will use the docks. List each truck’s length, width,height and bed height. 2013 Nova Technology InternationalAll Rights Reserved

DOCK PLANNING STANDARDSSee Figure 21 through Figure 26 for the dimensions ofcommon truck and trailer designs. Note that weight offreight can cause a variance of up to 6 in. in trailer andbed heights. The dimensions may also be affected byair suspension systems. Use Figure 21 through Figure26 for preliminary design, but obtain actual truckdimensions before making final design decisions.LRAHFigure 24: Refrigerated TruckLRALHRAHFigure 21: Container TruckFigure 25: Semitrailer, RoadLRALHRABHFigure 22: Semitrailer, CityFigure 26: Flatbed TruckLRATable 4Truck DimensionsHType ofVehicleFigure 23: Straight Truck 2013 Nova Technology InternationalAll Rights Flatbed55'–70'48"–60"–96"–102"9

DOCK PLANNING STANDARDSSea ContainersUnderride Protection BarsSea containers and refrigerated containers can havetrailers with heights of up to 62 in. Facilities that mustservice sea containers may also frequently servicelow-bed trucks. The height difference can be from 30to 62 in. Consider designing docks of various heightsor installing equipment such as hydraulic truck levelersor elevating docks. Typical container sizes are listed inTable 5.The underride protection bar, called the Rear ImpactGuard (RIG) bar, is mounted at the rear of the trailer(Figure 27). Restraint devices attach to the RIG barto prevent the truck from being driven away beforeloading or unloading is complete.Table 5EquipmentInteriorDimensionsDoorOpening45 ft High CubeContainerL: 44' 6-1/2"W: 7' 8-1/4"H: 8' 10"W: 7' 8"H: 8' 5-3/4"40 ft High CubeContainerL: 39' 6-1/2"W: 7' 8-1/4"H: 8' 9-1/2"W: 7' 8"H: 8' 5-3/4"40 ft Dry FreightContainerL: 39' 6-1/2"W: 7' 8"H: 7' 9-1/2"W: 7' 6"H: 7' 5-1/2"20 ft Dry FreightContainerL: 19' 5"W: 7' 8"H: 7' 9-1/2"W: 7' 6"H: 7' 5-1/2"20 ft Open TopContainerL: 19' 5"W: 7' 8"H: 7' 6"W: 7' 6"H: 7' 4-1/2"40 ft Open TopContainerL: 39' 6"W: 7' 8"H: 7' 5-1/4"W: 7' 5-1/2"H: 7' 5-1/4"45 ft High Cube ReeferContainerL: 42' 11-13/16"W: 7' 6-5/16"H: 8' 2-3/4"W: 8' 1-1/8"H: 7' 6-1/8"40 ft High Cube ReeferContainerL: 37' 11"W: 7' 6"H: 8' 2"W: 7' 6"H: 8' 1/2"40 ft Reefer ContainerL: 36' 9"W: 7' 4"H: 7' 2"W: 7' 3"H: 7' 2"20 ft Flat RackContainerL: 18' 8-1/2"W: 8'H: 7' 7-1/2"–40 ft Flat RackContainerL: 35' 9-1/4"W: 7' 6"H: 6' 10-1/2"–40 ft ArtificalTweendeckL: 39' 7"W: 7' 3-1/4"–40 ft Collapsible FlatRackL: 39' 7-1/2"W: 6' 11-1/2"H: 6' 8-1/4"–10Figure 27Set the Dock HeightThe most important characteristic of the loading dockdesign is the height of the dock. The dock height mustmatch the height of the docking trucks. The heightdifference between the dock and the trailer bed shouldbe as small as possible. The dockleveler bridgessome height difference, but the incline should notbe too steep. A steep incline can cause insufficientforklift underclearance, and it increases maintenancedemands on the equipment.To determine the dock height, find the midpoint of thebed heights of the expected trucks. Most trucks requirea dock height of between 46 and 52 in.See Table 6 for dock heights that create leve

DESIGN THE SITE Safety The Material Transfer Zone (MTZ), which acts as a bridge between the truck and warehouse, is a dangerous place where safety must be the most important consideration. Safety is often considered only after a serious accide