Innovative steps to reduce risk for motorway workers

Posted on August 25th, 2015 by James Luckhurst

Screen Shot 2015-04-29 at 11.38.40When at work, most of us don’t have to walk across high speed roads carrying heavy objects, but that is exactly what the workers who install signs for road works have to do every night on our motorways and dual carriageway roads. This has been normal practice for decades, but TRL has been working closely with Highways England (formerly Highways Agency) and the Road Workers’ Safety Forum to eliminate the need for road workers to undertake this high-risk activity.

Road workers installing (or removing) road works signing are at high risk of fatal or serious injury when working on high speed roads. One of the highest risk situations is crossing a live carriageway as all the sign equipment needs to be carried across live lanes by road workers. In support of the Highways England ‘Aiming for Zero’ strategy a work programme, led technically by TRL with financial and practical support from Highways England and the Road Workers’ Safety Forum (RoWSaF), was started in 2009 with the aim to eliminate road worker live carriageway crossings associated with Temporary Traffic Management (TTM) signing.

Research showed two potential approaches were possible; omit specific pairs of signs or all the offside (central reservation) signs. One potential barrier to either solution was the unknown impact on driver behaviour. If omitting some or all signs made road workers safer at the expense of road user safety, this would simply transfer risk from one group to another. The ideal situation was to demonstrate via operationally- focused research that road user safety was unaffected by actions designed to improve road worker safety.

Driving simulator trials were initially carried out at TRL to determine how driver behaviour would change if two of the five advance warning sign pairs were removed. This provided a completely safe environment in which to explore driver reactions and performance, which showed that driver behaviour was unaffected when removing sign pairs at 600 and 200 yards. Actual on-road trials then validated the simulator results, showing that driver behaviour did not change with sign pairs removed.

On the strength of the scientific evidence, the Highways Agency issued guidance in 2011 enabling this Sign Simplification technique to be used to reduce carriageway crossings substantially. This reduced risk to road workers but elimination of risk required a different approach. This was Off Side Sign Removal (or OSSR), where all the central reserve signs were omitted. This was tested using the proven on-road trial method used for Sign Simplification and developed in stages, with successful stages implemented immediately to reduce live carriageway crossings.

In summary, each trial in the development of OSSR showed that the technique has little or no impact on traffic behaviour under the conditions tested. Extensive objective monitoring and post- implementation evaluation confirmed that there has been no perceptible change in traffic behaviour at road works since OSSR was introduced.

The impact of this change on road worker risk is considerable with road worker injury risk decreased by 24 – 8%. More importantly, road workers are no longer forced to cross high speed dual carriageways to place signs in the central reservation as there is a proven alternative that is safe for road workers and road users.