A lorry or trailer must be fitted with an underrun (otherwise known as a bumper) on the back. An underrun prevents other road users from ending up underneath the vehicle in the event of a collision. The requirements are laid down in ECE Regulation 58.
"The new regulations on underride protection have a positive effect on the safety of fellow road users, but also major consequences for constructors. Expertise in this area is necessary to find the right solution."
What is changing in the new ECE R58-03 guidelines?
The stricter requirements affect the construction, height, location and mounting of the bumper bar on the truck. And in some cases, the truck's chassis must also be reinforced. The biggest changes in the new ECE R58-03 directive for vehicles >8t in unladen condition;
- the underrun must be able to withstand higher forces at 5 test points
- the height of the underrun profile was 100 and is now 120 mm
- the more stringent requirements that are being placed on the installation of the underrun on the vehicle
- the height from the ground to the underrun (the footboard height) was 550 and is now 450 mm
- the distance from the back of the vehicle to the underrun structure must not exceed 400 mm.
What do the new requirements mean for the structure and the vehicle?
The underrun must be able to withstand higher forces at 5 test points. This has consequences for the structure. The underrun structure must be made heavier or from a different grade of steel. In many cases, this causes the weight of the underrun structure to increase, potentially causing the total weight of the vehicle to increase. This does not necessarily have to be the case, of course; an engineer will try to recover weight in other places (such as by using lightweight toolboxes) in order to keep the useful load capacity the same. However, the vehicle structure must be made stronger. If calculations show that the structure meets the requirements, a practical test will often not be required. Each underrun structure must include a distinct and indelible seal of approval. Any changes to the structure must be reported to the RDW at all times.
Exceptions to underrun requirements
Special requirements apply to dump trucks and vehicles that have tailgates. For tractor units and vehicles where it is not possible to use an underrun structure as it would render the vehicle unusable, an exemption may be requested from the RDW in the Netherlands.
Our underrun supplier Pommier has adapted its entire range to the new R58-03 requirements. This ready-made product line has no fewer than 54 versions, so there is always one underrun that best suits your customer's requirements. Naturally, all Pommier bumpers are European certified and meet all new legal requirements and dimensions. You can find the most important underruns online.