Heavy Vehicle National Law – Mass Contraventions

The Heavy Vehicle National Law (HVNL) is the primary law governing the mass management for heavy vehicles. Heavy vehicles are defined as vehicles that exceed 4.5 tonne gross vehicle mass.[1] Mass management law aims to improve public safety by reducing risks arising from overweight vehicles and to minimise the impact of overweight vehicles on road infrastructure or public amenity.[2] This is achieved through imposing requirements for mass, as well as restricting access to roads for certain heavy vehicles.[3] Overweight vehicles are at risk of overturning which can cause a serious injury or death.

Duty

The driver has a duty to ensure the vehicle and its load complies with the mass requirements applying to that vehicle.[4] Under the Chain of Responsibility this duty can also extend to other parties in the supply chain, which can include the driver’s employer, consignor, consignee, transport operator, loader, packer, or loading manager.[5] The mass requirements include:

  1. The tare mass of heavy vehicles
  2. The total mass of the heavy vehicle including the load
  3. The mass on tyres, axles, or axle groups of heavy vehicles
  4. Mass limits relating to axle spacing
  5. General mass limit applying to the vehicle or components[6]

Categories of Contraventions

There are three categories of contraventions under the HVNL for mass management offences. The differences in categories depend on the severity of the breach, based on the extent the mass limits have been exceeded. The categories are:

  1. Minor risk breach
  2. Substantial risk breach
  3. Severe risk breach

A severe risk breach is the most serious offence category for mass management contraventions. An offence is classified as a severe risk breach if the mass equals or exceeds 120% of the maximum mass permitted for that vehicle.[7] An example of this would be if the drive axle group of a vehicle was detected to weigh 25,000kg over the statutory limit of 16,500kg. The breach would have exceeded the maximum mass permitted limit for that vehicle by 151.51% and therefore would be classified as a severe risk breach.

An offence is classified as a substantial risk breach if the mass equals or exceeds 105% or 0.5 tonne (which ever is higher) of the maximum mass permitted for that vehicle.[8] If the mass measured is below 105% of the maximum mass permitted for that vehicle, it is classified as a minor risk breach.[9]

Contraventions can be detected by the National Heavy Vehicle Regulator (NHVR) or Victoria Police by checking of compliance to mass requirements using a weighbridge, portable scales or other calculation methods.

Legal Mass Limits

Manufacturer’s Mass Limit

The first mass limit applying to all heavy vehicles is the manufacturer’s mass limit. This is the first requirement duty holders must comply with in ensuring they comply with their duties in relation to mass management.

Manufacturer’s mass limits can include limits on the Gross Vehicle Mass (GVM), Gross Combined Mass (GCM), front axle and suspension limit and rear axle and suspension limit. This limit is prescribed by the manufacturer for that particular vehicle. If the manufacturer’s mass limit is lower than the General Mass Limit (GML) or an exception mass limit, the manufacturer’s mass limit applies.[10]

General Mass Limits (GML)

General Mass Limits (GML) is the default standard for all heavy vehicles to comply with once they comply with the manufacturer’s mass limits. However, certain mass limits of this standard may not apply if the duty holder has an exemption or accreditation for higher mass limits discussed in the next section.

The GML prescribes mass limits based on the type and configuration of the vehicle. It also prescribes mass limits for individual axles and axle groups, as well as mass limits for axle spacings of a heavy vehicle. The GML is contained in Schedule 1 of the Heavy Vehicle (Mass, Dimension and Loading) Regulation 2013 (Vic) and published on the NHVR’s web site.

An example of GML for certain heavy vehicles and axle groups are listed below for comparative purposes. Note these are not the full requirements and should not be relied on as such.

Examples of GML maximum vehicle mass:

  • 4 Axle Semitrailer – Maximum mass under 31.5 tonnes
  • 5 Axle Semitrailer (3 rear axle) – Maximum mass under 35.0 tonnes
  • 6 Axle Semitrailer – Maximum mass under 42.5 tonnes

Examples of GML axle mass limits:

  • Tandem axle group fitted with single tyres on all axles with section widths of:
    • less than 375mm = 11.0 tonnes maximum
    • between 375mm and 450mm = 13.3 tonnes maximum
    • More than 450mm = 14.0 tonnes maximum[11]

Mass Limit Exceptions

There are exceptions under the HVNL which can exempt operators from certain GML requirements and provide higher mass limits.

 Concessional Mass Limits (CML)

Concessional Mass Limits (CML) allow operators to carry higher mass compared to the GML in some areas. CML is only available to operators accredited under the National Heavy Vehicle Accreditation Scheme (NHVAS) for mass management. Under this accreditation, operators are required to comply with eight mass management standards to demonstrate risks arising from higher mass limits are adequately managed. The eight standards include responsibilities, vehicle control, vehicle use, records and documentation, verification, training and education, internal review and maintenance of vehicle suspension. Documentation of the CML accreditation is required to be carried in the vehicle.

CML can allow operators to carry mass of a maximum of 5% higher than GML requirements for some limits. This is limited to a maximum of 1 tonne increase from GML for vehicles of a gross mass up to 55 tonnes and a maximum of 2 tonnes increase from GML for vehicle combinations of a gross mass exceeding 55 tonnes.[12] However CML does not allow higher mass limits for all axle groups and configurations. For example, GML would still apply to the quad-axle group mass limit, as CML does not allow for higher limits for this axle group.

An example of CML for certain heavy vehicles and axle groups are listed below for comparative purposes. Note these are not the full requirements and should not be relied on as such.

Examples of CML maximum vehicle mass limits:

  • 4 Axle Semitrailer – Maximum mass under 32.0 tonnes
  • 5 Axle Semitrailer (3 rear axle) – Maximum mass under 36.0 tonnes
  • 6 Axle Semitrailer – Maximum mass under 43.5 tonnes

Examples of CML axle mass limits:

  • Tandem axle group fitted with single tyres on all axles with section widths of:
    • less than 375mm = 11.5 tonnes maximum
    • between 375mm and 450mm = 13.8 tonnes maximum
    • More than 450mm = 14.5 tonnes maximum[13]
Higher Mass Limits (HML)

Higher Mass limits may allow operators to carry higher mass compared to CML and GML for some configurations. HML is also only available to operators accredited under the NHVAS for mass management. This is the highest mass accreditation for mass management however is subject to conditions. Vehicles used for HML must be fitted with a certified road friendly suspension system to reduce the risk of damage to road infrastructure.[14]

The vehicles must also meet the vehicle requirements of schedule 5, such as, it must not be a class 1 vehicle type (agricultural vehicles).[15] The HML will also only apply to specific roads authorised for HML and cannot be used on all roads.[16] Operators are required to comply with the above eight mass management standards to demonstrate risks arising from higher mass limits are adequately managed. Documentation of the HML accreditation is also required to be carried in the vehicle.

However HML also does not allow higher mass limits for all axle groups and configurations. For example, GML would still apply to the quad-axle group mass limit, as HML does not allow for higher limits for this axle group.

An example of HML for certain heavy vehicles and axle groups are listed below for comparative purposes. Note these are not the full requirements and should not be relied on as such.

Examples of HML maximum vehicle mass:

  • 4 Axle Semitrailer – Maximum mass under 32.0 tonnes
  • 5 Axle Semitrailer (3 rear axle) – Maximum mass under 37.5 tonnes
  • 6 Axle Semitrailer – Maximum mass under 45.5 tonnes

Examples of HML axle and axle group mass limits:

  • Single drive axle on a bus – 10 tonnes
  • Tandem axle group – 17 tonne
  • 6 tyred tandem axle group – 14 tonnes
  • Tri-axle group – 22.5 tonnes [17]
Quad Axle Group Mass Exception

A quad-axle group means a group of four axles, under GML the quad-axle group on a heavy vehicle has a maximum mass limit of 15 tonnes or 20 tonnes depending on the section width of the tyre.[18] CML and HML does not allow a higher mass limit for this axle group.[19]

The quad-axle group mass exception allows for the maximum mass limit for this axle group to be increased to 27 tonnes subject to conditions. The conditions require all axles in the quad-axle group to be fitted with dual tyres and the vehicle to be approved under the Performance Based Standard (PBS) to carry a mass of 27 tonnes on the quad-axle group. The vehicle is required to comply with PBS standards and with any conditions of approval.[20]

PBS Approved Vehicles

PBS is a scheme which allows vehicles to be assessed and approved for higher limits in relation to mass and other limits compared to standard vehicles. PBS approved vehicles are of general higher standard than standard vehicles, to meet the high standard requirements of the PBS scheme.

PBS approved vehicles may be newer, have advanced safety features and be specifically designed for the task. If PBS approved vehicles are approved for higher mass limits, then the prescribed mass limit (GML,CML,HML) does not apply.[21] PBS vehicles are assessed against sixteen stringent safety standards which includes standards for powertrain, low speed performance, vehicle stability and high-speed performance.

As part of the PBS conditions, operators are required to be accredited under the NHVAS for mass management amongst other conditions.

One Tonne Tri-axle Mass Transfer Allowance (‘Tri-axle mass exception’)

A tri-axle group means a group of three axles, under GML the tri-axle group on a heavy vehicle has a maximum mass limit of 20 tonnes. The tri-axle mass exception allows the tri-axle group to carry a higher mass limit of 21 tonnes.[22] However the maximum mass capacity for the vehicle does not increase, but allows for a greater flexibility to distribute the mass onto the vehicle, by the increased mass limit for that axle group.[23] The heavy  vehicle is still required to comply with other maximum mass limits that may apply under the GML. This exception only applies to GML and does not apply to CML or HML or other permits.[24]

Other Exceptions

NHVR also has the power to grant exemptions to mass limit requirements for certain heavy vehicles (class 1 and 3) by a Commonwealth Gazette notice or permit.[25] An exemption under a Commonwealth Gazette notice can be issued for a maximum period of 5 years and an exemption under a permit can be issued for a maximum period of 3 years.[26]

Risk Controls

Duty holders should implement effective risk controls to manage the risks arising from overweight vehicles, which may include:

  1. Determining and communicating mass limit requirements to relevant persons
  2. Implementing systems to calculate mass, such as weighbridge, vehicle or portable weighing scales, air pressure gauges, liquid density calculations
  3. Reviewing and managing routes to identify and avoid any hazardous roads which may impact vehicle stability
  4. Utilising vehicles with a higher standard of safety measures and stability
  5. Implementing procedures to ensure vehicles comply with mass limit requirements
  6. Conducting random inspections to verify compliance with mass requirements
  7. Scheduling regular maintenance to ensure vehicles and any relevant mass compliance equipment is calibrated and maintained
  8. Implementing procedures to ensure weights are evenly distributed on vehicles
  9. Conducting regular training on the risks of overweight vehicles and mass management requirements
  10. Conducting regular auditing of mass management systems to identify any deficiencies and ensure continuous improvement

 


[1] Heavy Vehicle National Law 2013 (Vic) section 6.

[2] ibid section 94.

[3] ibid section 94(2).

[4] ibid section 96.

[5] ibid section 26A.

[6] ibid section 95(2).

[7] ibid section 100.

[8] ibid section 99.

[9] ibid section 98.

[10] ibid  section 8.

[11] Heavy Vehicle (Mass, Dimension and Loading) Regulation 2013 (Vic) schedule 1.

[12] ibid schedule 2.

[13] ibid schedule 2.

[14] ibid schedule 5.

[15] ibid schedule 5.

[16] ibid schedule 5.

[17] ibid schedule 5.

[18] ibid schedule 1.

[19] ibid schedules 1 and 5.

[20] ibid schedule 4.

[21] Heavy Vehicle National Law 2013 (Vic) section 96(4).

[22] Heavy Vehicle (Mass, Dimension and Loading) Regulation 2013 (Vic) schedule 5A.

[23] ibid schedule 5A.

[24] ibid schedule 5A.

[25] Heavy Vehicle National Law 2013 (Vic) sections 117, 122.

[26] ibid sections 117, 122.