On Board Mass (OBM)

On Board Mass (OBM) systems approved by Transport Certification Australia (TCA) may be used as a risk management option by road managers to allow specific access on road networks in NSW.

OBM systems monitor all the axle groups in the vehicle combination and provide the mass readings of these axle groups to the IAP system.

Approved OBM systems linked to the IAP are administered by Transport Certification Australia (TCA) and allow Transport for NSW and other road managers in NSW to grant access to routes approved as suitable that may have previously been unavailable for these vehicle types due to identified infrastructure risks.

Operators must only use certified IAP OBM service providers that can supply approved OBM systems linked to the IAP.

Vehicles requiring OBM

Approved OBM systems linked to the IAP are currently in use by Transport for NSW as an agreed road access condition for specific access for the following Performance Based Standards (PBS) combinations operating on approved Transport for NSW roads in NSW:

  • Some PBS Level 2 access category B and Level 3 access category A Quad Axle B-double combinations
  • Some PBS Level 2 access category B A-double combinations.

Registered operators seeking to operate the above vehicle combinations or other restricted access heavy vehicles over sensitive infrastructure or in elevated risk locations may be able to gain access by using an approved OBM system, enrolling in an IAP OBM scheme with Transport for NSW and applying for the appropriate access permit from the NHVR to travel in NSW.

Enrol in the OBM under IAP

Where OBM is an agreed condition of road access in NSW, the vehicle must have an NSW IAP Certificate of Enrolment showing the vehicle type enrolled in the IAP and that it is monitored in an OBM scheme.

Please note: If the vehicle is already enrolled in the IAP or OBM in another jurisdiction, the vehicle will still be required to separately enrol in the IAP OBM with Transport for NSW for travel in NSW.

To enrol in the OBM, registered operators must follow the steps shown in Enrol in the IAP with Transport for NSW.

All enrolments in the IAP or OBM are processed free of charge.

Your vehicle will require an access permit to operate in NSW for the vehicle type enrolled in the IAP, please apply for an access permit from the NHVR.

Why is OBM required and what are the benefits?

OBM enables Transport for NSW and other road managers to provide greater access to their managed road network, particularly infrastructure which is restricted due to heavy vehicle mass capacity, by provided greater assurance to Transport for NSW (and other road managers) that the heavy vehicles are operating within the approved mass limit for that part of the network and on routes that have been approved as suitable for their use.

Other operator interests

Operators who believe their productivity may be improved by using an approved OBM system as a risk management tool to extend their road network access may contact Transport for NSW Heavy Vehicles Branch by email at iap@transport.nsw.gov.au to enquire as to whether OBM may provide them with a productivity opportunity through improved road network access.