Load Classifications

AS3996 : 2006 - Access Covers, Road Grates and Frames

Access covers and grates shall be designated by classes A, B, C, D, E, F and G according to load capacity as set out in the table below. The design loads as specified in below table, shall be used for testing.

The appropriate class for a cover or grate depends upon the place of installation. Some places of installation, relative to class, are outlined below. The selection of the appropriate class is the responsibility of the designer and where there is doubt the stronger class shall be selected.

  Class Rating Typical Use Nominal Wheel Load (kg) Serviceability Design Load (kN) Ultimate Limit State Design Load (kN)
Loading Class A A Areas (including footways) accessible only to pedestrians and pedal cyclists and closed to other traffic (extra-light duty) 330 6.7 10
Loading Class B B Areas (including footways and light tractor paths) accessible to vehicles (excluding commercial vehicles) or livestock (light duty) 2,670 53 80
Loading Class C C Malls and areas open to slow moving commercial vehicles (medium duty) 5,000 100 150
Loading Class D D Carriageways of roads and areas open to commercial vehicles (heavy duty) 8,000 140 210
Loading Class E E General docks and aircraft pavements (extra heavy duty – E) 13,700 267 400
Loading Class F F Docks and aircraft pavements subject to high wheel loads (extra heavy duty – F) 20,000 400 600
Loading Class G G Docks and aircraft pavements subject to very high wheel loads (extra heavy duty – G) 30,000 600 900


  1. Nominal wheel loads are given for guidance only. Consideration should be given to the type, size and pneumatic pressure of the load applied.
  2. Class B design loads exceed AS 5100.2 requirements for footway loading.
  3. Class D design loads exceed AS 5100.2 requirements for a W80 wheel load.
  4. Class C units are based on an intermediate load.
  5. The serviceability load is set at 2/3 of the ultimate limit state design load.
  6. A force of 1 kN approximately equal to the weight of 100 kg.