What are the Mass and Dimension Requirements under the Chain of Responsibility?

Heavy Vehicle National Law (HVNL) and Chain of Responsibility (CoR)

Under the Heavy Vehicle National Law:


  • “Parties in the supply chain must ensure the vehicle, the vehicle’s components and load, comply with the mass requirements applying to the heavy vehicle.”
  • “Parties in the supply chain must ensure the vehicle, the vehicle’s components and load, comply with the dimension requirements applying to the heavy vehicle.”


Under the Heavy Vehicle National Law and the specific Chain of Responsibility Duties no heavy vehicle may travel on a road when loaded in excess of its allowable mass and dimension limits. General dimension and mass limits apply to all heavy vehicles, unless operating on approved route or under an accreditation or exemption, or a permit that allows an approved increase in mass and dimension limits at that time.


Overloaded and oversize heavy vehicles have a disproportionate impact on public infrastructure and where an overloaded heavy vehicle is involved in a crash, the likely outcomes are more serious. Mass can also be an issue in heavy vehicle stability. High, dense loads result in a high centre of gravity and can increase the risk of roll-overs.


Mass, dimension and restraint can also be related because a poorly restrained and distributed load can result in instability, and it can result in other vehicle and road surface impacts.


Mass Limits

Mass limits are set according to the following mass management options which include:

  • General Mass Limits (GML)
  • NHVAS Concessional Mass Limits (CML)
  • NHVAS Higher Mass Limits (HML)
  • Over-size and Over-mass Permit or Notice
  • Grain Harvest Mass Management Scheme
  • Livestock Loading Mass Management Scheme


General Mass Limits, or GML apply to all heavy vehicles and is the allowable mass unless the vehicle is operating under an accreditation or an exemption under the HVNL. The National Heavy Vehicle Regulator or NHVR, has developed a “Common Heavy Freight Vehicle Configurations” chart that can be used for guidance.


Concessional Mass Limits (CML) allow a heavy vehicle to operate mass limits 5% above the GML where the Operator is accredited under the National Heavy Vehicle Accreditation Scheme (NHVAS).


General Dimension Limits

General dimension requirements may relate to the dimensions (width, height, length, overhang) of a:

  • Heavy vehicle or combination (together with its equipment);
  • Component of a heavy vehicle or combination; and
  • Heavy vehicle’s load.


The general WIDTH limit for a vehicle is 2.5 metres.

The general HEIGHT limit for a vehicle is 4.3 metres.


The maximum allowable length of a heavy vehicle is:

  • For a combination other than a B-double, road train or a car carrier—19 metres
  • For a B-double—25 metres
  • For a road train—53.5 metres
  • For a car carrier —25 metres
  • For another vehicle—12.5 metres


Managing Mass & Dimension Limits in your Business

The general requirements for Managing Mass & Dimension Limits in your Business include:

  • Conducting a risk assessment of your mass and dimension obligations.
  • Documenting mass and dimension limit policies and procedures that outline the control measures.
  • Consulting with other parties on how they manage mass and dimension requirements – for example, requesting a copy of their mass & dimension risk assessment, policies and procedures.
  • Conducting regular contract reviews of the effectiveness of controls implemented by others in the supply chain.
  • Ensuring contracts and agreements do not contain incentives that may cause or encourage the parties to breach mass and dimension requirements.
  • Ensuring Commercial arrangements include prescriptive requirements to comply with legal obligations.


Zenergy eLearning Program – Chain of Responsibility (CoR) for Operational Staff

This online course introduces you to requirements and obligations of Fatigue Management, Speed Compliance and Heavy Vehicle Safety and Roadworthiness, Load Management including Mass and Dimension and Load Restraint as they relate to Chain of Responsibility and the Heavy Vehicle National Law and the key aspects of these risks and how to manage them in accordance with the Heavy Vehicle National Law.


This course includes Module 5. Mass and Dimension Limits – Provides an overview of the Heavy Vehicle National Law (HVNL) and Regulations requirements and obligations for Mass and Dimension Limits.


Click on the following link to review further course details:  Chain of Responsibility (CoR) for Operational Staff


Zenergy – Heavy Vehicle National Law and Chain of Responsibility (CoR)

Zenergy experienced consultants can assist in the development of CoR Transport Safety Management System (TSMS) documentation, conducting independent audits of your Management System documentation for management of transport safety, including Chain of Responsibility (CoR), to ensure it meets your responsibilities under the Heavy Vehicle National Law (HVNL).



For more information on our services feel free to email us at info@zenergygroup.com.au or call 1300 333 400.

Chain of Responsibility (CoR) Training

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