Mass exceptions

There are exceptions under the Heavy Vehicle National Law (HVNL) which provide alternate mass limits when certain other requirements are met.

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Concessional Mass Limits

Concessional Mass Limits (CML) allows operators accredited under the National Heavy Vehicle Accreditation Scheme (NHVAS) to utilise mass limits above the national general limits.

For more information see Concessional Mass Limits.

Higher Mass Limits

Under the Heavy Vehicle National Law (HVNL), Higher Mass Limits (HML) provides a significant increase in the productivity of road freight transport heavy vehicles by allowing particular vehicles to access additional mass entitlements, subject to conditions.

For more information see Higher Mass Limits.

Quad axle group limits

Quad axle group limits (QML) provide semitrailers, B-doubles, and other PBS combinations fitted with quad-axle groups to operate at mass limits up to 27t on a defined road network.

For more information see Quad-axle group vehicle combinations.

1-Tonne Tri-Axle Mass Transfer Allowance

The 1-Tonne Tri-Axle Mass Transfer Allowance (1TMTA) provides increased mass limits on tri-axle groups so that they may be operated up to 1 tonne (t) above the tri-axle group 20t GML provided any additional mass loaded onto each tri-axle group is offset onto other non-steer axle or single axle groups.

For more information see 1-Tonne Tri-Axle Mass Transfer Allowance information sheet.

Euro VI vehicle mass transfer allowance

Euro VI vehicle mass transfer allowance provides up to 0.5t of the single steer axle mas limit to be offset onto the vehicle’s drive axle group.

The MDL Regulation provides mass limits for the following:

  • Euro VI vehicle (complying steer axle)
  • Euro VI vehicle (single steer axle)
  • Euro VI vehicle (twinsteer)

The Euro VI vehicles above must meet the exhaust emissions requirements contained in Australian Design Rule (ADR) 80/04  or later, as well as a number of other requirements as per the MDL Regulation. 

For more information see ADR 80/04 (Euro VI) emissions mass limits increase - Information sheet (PDF, 269KB) and National Class 3 Euro VI Vehicle (wide-spaced twinsteer) Mass Exemption Notice Operator's Guide.

The Department of Infrastructure, Transport, Regional Development, Communications and the Arts has further information on the impact of ADR 80/04 and its health benefits at Questions and answers on the new ADR 80/04.

Euro VI (ADR 80/04) heavy vehicle emissions and mass provisions

The Australian Government introduced a new emissions standard for new heavy vehicles last year through Australian Design Rule (ADR) 80/04, which aligns with the European Euro VI standard.

To meet this higher emissions standard, ADR 80/04 vehicles incorporate additional and more advanced emissions systems. As a result, these vehicles are generally heavier than equivalent ADR 80/03 (Euro V) and earlier models.

In response, the Heavy Vehicle (Mass, Dimension and Loading) National Regulations were amended to increase mass limits for ADR 80/04 heavy vehicles.

Current regulatory position

An issue has been identified in the Heavy Vehicle (Mass, Dimension and Loading) National Regulations that affects the operation of the Euro VI mass exception. In its current form, the legislation does not fully reflect the approved policy intent of the reform.

This issue is being addressed by the National Transport Commission (NTC), and amendments to the legislation are intended.

NHVR approach

The NTC has confirmed that the policy intent behind this regulation is that Euro VI vehicles may have up to 500kg additional mass distributed across the steer and drive axles, provided a 315mm tyre is fitted to the steer axle if this axle is loaded to more than 6.5 tonnes and no manufacturers' ratings are exceeded.

While amendments are being made, the NHVR will administer and enforce the Euro VI mass provisions in line with the approved policy intent. This includes providing advice to our on-road Safety and Compliance Officers and updating the processes for operators to obtain PBS Vehicle Approvals that make use of the approved policy intent. This approach provides clarity and consistency for industry during the interim period.

Further updates will be provided as amendments progress.