Concessional Mass Limits

Concessional Mass Limits (CML) allow an operator to operate at mass limits above the national general limits provided the operator is accredited under the National Heavy Vehicle Accreditation Scheme (NHVAS). Companies wishing to benefit from the productivity gains of CML, are required to meet the eight standards of compliance in the National Heavy Vehicle Regulator’s (NHVR) Mass Management Accreditation Guide (PDF, 867KB).

What are the limits for CML?

Mass limits for CML are set at 5% above the General Mass Limit (GML), subject to:

  • a maximum of 1 tonne for a vehicle or vehicle combination with an allowable gross mass not exceeding 55 tonnes
  • a maximum of 2 tonnes for vehicle combinations with an allowable gross mass exceeding 55 tonnes
  • an upper limit on axle and axle group mass as described in the following Concessional mass limits for axle groups table.

Note: In Queensland, as a means of providing more flexibility to operators, the mass limits that apply in CML are extended to include the following mass limit increases:

  • In Queensland a maximum increase of 3 tonnes for vehicle combinations with an allowable gross mass exceeding 85 tonnes but not exceeding 120 tonnes
  • In Queensland a maximum increase of 4 tonnes for vehicle combinations with an allowable gross mass exceeding 120 tonnes.

Concessional mass limits for axle groups

See the Concessional Mass Limits fact sheet (PDF, 300KB) for axle group mass limits.

Ineligible vehicles

The following vehicles and combinations are not eligible for CML due to safety reasons or because they are eligible to operate at masses higher than those afforded by CML:

  • a bus
  • a combination consisting of a truck and pig trailer
  • special purpose vehicles, agricultural machine or agricultural implement
  • vehicles operating under any other permit, notice or other exemption that allows axle or axle group loads over those specified in the Heavy Vehicle National Law (HVNL).

Suspension maintenance

Standard 8 of Mass Management accreditation requires all accredited vehicles, including trailers supplied by other parties, to have their suspension systems maintained and replaced according to the manufacturer’s (or a qualified mechanical engineer’s) specification. Operators who have vehicles with air suspensions should refer to the Australian Road Transport Suppliers Association (ARTSA) Air Suspension Code.

The CML is not linked to a requirement for road friendly suspension nor does it restrict a vehicle or combination from routes that would have been used when complying with general mass limits. However, suspension must be compliant with the Australian Design Rules (ADR).

Hire trailers

Where a hire trailer is used by a mass accredited operator, a Statement of Compliance stating that the suspension of the trailer has been maintained equivalent to Standard 8 must accompany the trailer and be produced if requested. This will require that the hirer of the trailer to have an auditable maintenance system that demonstrates the trailer’s suspension has been maintained to Standard 8. See Mass Management accreditation.

Access restrictions

Operators of vehicles at CML have access to the same network as currently applies to the particular vehicle class, except where prohibited by a load limit specified for a road, bridge or causeway by a sign or notice.

Other requirements

Heavy vehicles must not exceed manufacturers’ ratings and must comply with the axle spacing formulae appropriate to GML.

See also the Concessional Mass Limits fact sheet (PDF, 300KB).