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Clarification around FUPS and 69.1t B-Double Mass Limit

We have recently received several enquiries regarding the regulations surrounding Front Under-Run Protection Systems (FUPS) and the 69.1t B-Double Combination Mass Limit.

Front Under-Run Protection Systems (FUPS)
Mass limit regulations allow prime movers equipped with the following features to carry an additional 0.5 tonnes on the legal mass limit for the steer axle, raising it from 6.0 tonnes to 6.5 tonnes:
An engine compliant with ADR 80/01 (Euro IV).
Front under-run impact protection that meets UN ECE Regulation No. 93 or ADR 84.
Cabin strength that meets the requirements of UN ECE Regulation No. 29.
Typically, these trucks have been built from 2008 onwards.

Summary: It is essential to understand that simply having a prime mover fitted with FUPS/FUPD is insufficient; all the aforementioned conditions must be satisfied.

69.1t Combination Mass Limit
Road train-rated prime movers with steer tyres 375mm or wider are eligible for an additional 0.6 tonnes steer allowance, provided they meet the same conditions as the 0.5 tonnes allowance mentioned above. This results in a total additional mass limit of 1.1 tonnes on the steer axle, allowing for 7.1 tonnes instead of the standard 6.0 tonnes.
The National Class 3 Road Train Prime Mover Mass and Dimension Exemption Notice 2021 (No. 1) permits road train-rated prime movers to operate as a B-double or semitrailer.

Summary: Road train-rated prime movers may operate at 7.1 tonnes on the steer axle if they meet the FUPS/FUPD conditions and are fitted with tyres 375mm or wider.

If you would like to discuss this further, please feel free to call me at 0447 289 611 or fill out the contact form on our website.

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