Emergency refuge area simulation study

Greater use of the hard shoulder as an active running lane places increased pressure on use of the Emergency Refuge Areas (ERA) as safe havens in the event of a vehicle breakdown. Currently, more than 80% of ERA use is non-legal and non-emergency with a commensurate increase in exposure to risk. In addition there is evidence that stops can occur in the wrong place within ERAs which may have consequences for emergency vehicle access as well as the ability to leave the ERA safely and rejoin the carriageway. The aim of this driving simulator study was to evaluate drivers’ response and subjective evaluation of different ERAs designed to optimise their safe and effective use. Four design options were evaluated: 1) Low lit ERA at unlit motorway (night drive); 2) Unlit ERA at fully-lit motorway (night drive); 3) Small ERA format (total length reduced from 100 to 55m); 4) Revised ERA design (alternative road markings and position of emergency phone). 72 participants were asked to drive three routes in which they experienced a simulated breakdown requiring them to stop in an ERA. This allowed for the evaluation of drivers’ ability to exit the motorway and drivers’ stopping position within the ERA. By repairing the simulated fault, drivers were subsequently asked to rejoin the carriageway which in turn allowed for the evaluation of factors such as gap acceptance and speed choice. It was shown that the specific ERA designs differently affected driving behaviour and the results are discussed in the context of road safety and network performance. The simulator study was effective in identifying several critical design features that can be further explored in future research.