South Australian Class 3 Road Friendly Suspension Mass Exemption Notice 2022 (No.1)


  1. Purpose


1)      This Notice exempts certain heavy vehicles and combinations fitted with certified Road Friendly Suspension from mass requirements set out in the Heavy Vehicle (Mass Dimension and Loading) National Regulation (MDL Regulation), allowing operation at higher axle masses.


2)      This Notice revokes and replaces the South Australia Class 3 (Application of Higher Mass Limits) Mass Exemption Notice 2020 (No.1).


Note: This Notice removes references to Higher Mass Limits that existed in previous versions. Eligible vehicles are still granted access on South Australian Higher Mass Limits networks, but references to Schedule 5 of the Heavy Vehicle (Mass Dimension and Loading) National Regulation have been removed. The Notice is functionally identical to previous versions.

2.       Authorising Provision


1)      This notice is made under the following provision of the Heavy Vehicle National Law (HVNL):


a)      section 117 - Regulator’s power to exempt category of class 1 or 3 heavy vehicles


3.       Title


This Notice may be cited as the South Australian Class 3 Road Friendly Suspension Mass Exemption Notice 2022 (No.1).


4.       Commencement date


This Notice commences on 25 July 2022.


5.       Expiry date


This Notice expires on 9 February 2024.





6.       Definitions


1)      Unless otherwise stated, words and expressions used in this Notice have the same meanings as those defined in the HVNL and the National Class 2 Road Train Authorisation Notice and National Class 2 B-Double Authorisation Notice.


7.       Application


1)      This Notice applies to heavy vehicles or heavy vehicle combination that is a:


a)      rigid truck; or

b)      prime mover towing a semitrailer; or

c)       bus fitted with a single drive axle or a six-tyre tandem axle group at the rear; or

d)      B-double; or

e)      type 1 and type 2 Road Train.


2)      This Notice does not apply to a heavy vehicle combination that has:


a)      a tri-axle drive group; or

b)      a quad axle group.


3)      This Notice applies in South Australia.


4)      A vehicle to which this section applies is an eligible vehicle.


8.       Exemption - Prescribed mass requirements


1)      This notice exempts eligible vehicles from the following mass requirements specified in Schedule 1 of the MDL Regulation:


a)      Section 2 - Mass limits for a single vehicle or combination

b)      section 4 - Mass limits for a single axle or axle group

c)       section 5 - Mass limits in relation to axle spacing table 2, 3 and 4


2)      The exemptions in this section only apply to the extent provided under the conditional axle masses set out in section 9 of this Notice.



9.       Conditions - Axle mass limits


1)      An axle configuration described in Column 1 of Table 1 and a mass limit under Schedule 1 listed in Column 2 may have additional mass up to the limit listed in Column 3.



Table 1: Axle mass limits for non-articulated vehicles

Column 1

Column 2

Column 3

Axle Configuration

Prescribed axle mass limit (t) under Schedule 1

Additional axle spacing mass (t)

Single drive axle on buses fitted with 4 tyres



Tandem axle groups fitted with 6 tyres



Tandem axle groups fitted with 8 tyres



Triaxle group fitted with 12 tyres




2)      For a given axle spacing in a relevant axle spacing table, the axle group mass must not be increased by more than the additional amount provided in column 3 of Table 1.


3)      For the purpose of 2), a relevant axle spacing table is:


a)      For b-doubles – Table 3 of Schedule 1 of the MDL Regulation

b)      For road trains – Table 4 of Schedule 1 of the MDL Regulation

c)       For all other eligible vehicles – Table 2 of Schedule 1 of the MDL Regulation.


4)      On an eligible vehicle that is not a road train, if the steer axle is a complying steer axle then the steer axle may have a mass that does not exceed 6.5t.


Note: Regarding the exemption from section 2 of Schedule 1 of the MDL Regulation, a conditional total vehicle mass is not provided under this Notice. In practice, the total mass of an eligible vehicle may not exceed the sum of the axle masses of the vehicle as provided by this Notice.


10.   Conditions – Areas and Routes


1)      An eligible vehicle of a configuration stated in Column 1 of Table 3,  and complying with all of the conditions of this Notice, may operate on the network stated in Column 2.

Table 3: Networks for specified eligible vehicle configurations

Column 1

Column 2

Vehicle Configuration


Prime mover towing a semitrailer,

rigid truck or bus

19m Network (HML)

23m B-double

23m B Double (HML)

26m B-double

26m B Double (HML)

Vehicle Carrier up to 25m long

25m Vehicle Carrier (HML)

Type 1 Road Train up to 30m long

30m Road Train (HML)

Type 1 Road Train up to 36.5m long

36.5m Road Train (HML)

Type 2 Road train up to 53.5m long

53.5m Road Train (HML)

Type 2 AB Triple Road Train up to 42.0m long

PBS3B Network


Note: All networks are published the South Australian Department of Infrastructure and Transport and are available on its website.

The network map may contain conditions that only apply to particular sections of the network, or only at particular times. Conditions like these will usually be applied through the network map itself, but may also be published in the Operator’s Guide itself.

2)      For the purposes of section 121(1)(c) of the HVNL, a network set out in this section is a stated area and route to which this Notice applies.

3)      An eligible vehicle operating on a network stated in column 2 of Table 3 must comply with the following conditions relevant to it:


a)      Road conditions pursuant to section 160 of HVNL; and

b)      Travel conditions pursuant to section 161 of the HVNL; and

c)       Vehicle conditions pursuant to section 162 of the HVNL.


11.   Conditions – Mass Management Accreditation


The operator of an eligible vehicle with a tri-axle group exceeding 20.0t must hold Mass Management Accreditation.


12.   Conditions – Road friendly exemption


An axle operating at axle limits under Table 1 of section 9 and exceeding the General Mass Limits must be fitted with road friendly suspension.


Note: This means that an axle or axle group that is not using a mass exemption under section 8 and a conditional mass limit under section 9 is not required to have road friendly suspension.





Peter Caprioli

Executive Director (Freight and Supply Chain Productivity)

National Heavy Vehicle Regulator