#24 Motorcycle Underrun Protection

Motorcycle run-off-road (ROR) crashes tend to be most severe when riders impact solid roadside objects. While various types of barriers can prevent impacts with trees, roadside furniture and other objects, the barriers themselves can sometimes contribute to greater injury severity than if no barrier were present. The Federation of European Motorcyclists’ Association’s (FEMA) Safer Roads for Motorcyclists report (2023) cites statistics from various countries on barrier-related injury and fatality risks for riders. These include that:

• Motorcyclist injury risk of barrier crashes is twice that of non-barrier crashes

• Riders are 15 times more likely to be killed in a barrier crash than car occupants

Generally, risk of barrier crashes is highest on curves, and especially those with a non-standard or tightening radius on exits. Importantly, it is often riders’ impact with vertical barrier posts rather than horizontal railings which contribute to the greater injury severity outcomes. For common W-beam guardrails, this is a factor that can be treated successfully in many instances to improve rider safety.

Source: Safe Direction

Treatments

Motorcycle underrun protection systems are also referred to as “ground level road safety barriers” and “rub rails”. VicRoads describes the treatment as “an extra protection system underneath the main beam of roadside barriers to prevent riders from hitting the steel posts if they fall and slide”. Different suppliers offer a range of options in terms of design and materials to meet the general objective.

While widely accepted as effective and endorsed by road safety experts and motorcycle safety advocates alike, various studies quantifying the effects of underrun protection have produced different (positive) results. This variability may be due to the research methods used and the many variables to consider, including material types, installation, road and rider characteristics, and so on. However, Transport for NSW (TfNSW) research found a 20% reduction in severity of single vehicle ROR motorcycle crashes attributable to underrun protection.

Considerations

With or without underrun protection, FEMA recommends that barriers be positioned as far from the traffic lane as possible.  In Victoria, funding for underrun protection treatments may be available through the Victorian Motorcycle Safety Levy.