HVS Update 14-2021

Clarification on certain conditions within the Oversize Operating Conditions

Amendments to Clarify Operating Conditions

Please be advised that the following amendments have been made to the Class 1 Oversize Period Permit Operating Conditions and the Single Trip OSOM Vehicle Standard Operating Conditions:

  • Clause 5.1.1 of the Class 1 Oversize Period Permit Operating Conditions has been amended to allow RAVs up to 2.5 metres in width and 25 metres in length to operate on the Freeway.
  • The Swagman Roadhouse has been added to clause 5.8 Access to Service Stations under the Single Trip OSOM Vehicle Standard Operating Conditions.
  • The night travel provisions under clause 13 in the Single Trip OSOM Vehicle Standard Operating Conditions have been amended to reduce the need for OSOM Transport Management Plans.
  • The conditions relating to clearing built-up traffic have been amended. The requirements now only apply to RAVs in excess of 4.5 metres in width. Further clarification on these requirements is provided below. 

Clarification on Clearing Built-Up Traffic Behind an Oversize Vehicle

There has been some confusion regarding the conditions relating to clearing built-up traffic behind an oversize vehicle that was recently included in the oversize operating conditions. The conditions were included to ensure other road users were not disrupted for unreasonable periods that resulted in unnecessary risks being taken to overtake wide loads.

Traffic Escorts and pilots can facilitate clearing of built-up traffic wherever it is safe to do so. Some examples of where it is considered safe to clear built-up traffic is as follows:

  • Where the oversize vehicle can safely pull into a suitable parking bay to allow the built-up traffic at the rear to pass.
  • Where the oversize vehicle can safely pull into another suitable location adjacent to the carriageway such as a flat gravel area or similar. The oversize vehicle must be able to pull far enough to the left of the carriageway to provide sufficient clearance to allow the built-up traffic to overtake safely without crossing continuous centre lines.
  • Where the oversize vehicle can safely pull into a left turning lane or T-intersection. The oversize vehicle must be able to pull far enough to the left of the carriageway to provide sufficient clearance to allow the built-up traffic to overtake safely without crossing continuous centre lines.
  • Where the carriageway is wide enough to allow the oversize vehicle to pull far enough to the left of a lane, slow to a suitable speed (i.e. 60km/h or less) and provide sufficient clearance to allow the built-up traffic to overtake safely without crossing continuous centre lines.
  • Where a section of road is closed in accordance with an accepted Traffic Guidance Scheme, such as TGS RM0395-18-28 Facilitating Movement of Oversize Vehicle(s) Through Narrow Road Section. Once the oversize vehicle has cleared the narrow road section, the oversize vehicle can pull over to the far left of the carriage way, providing sufficient clearance to allow the built-up traffic to overtake while the road closure remains in place, even if the built-up traffic is required to cross a continuous centre line.
  • As documented in an accepted OSOM Transport Management Plan.  


For further information or clarification, please contact the Heavy Vehicle Helpdesk on 138 486 or email hvs@mainroads.wa.gov.au

Heavy Vehicle Services

15 September 2021

Acknowledgement of country

The Government of Western Australia acknowledges the traditional custodians throughout Western Australia and their continuing connection to the land, waters and community. We pay our respects to all members of the Aboriginal communities and their cultures; and to Elders both past and present.

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