Tunnel hazard detection in North Wales

The characteristics of road tunnels and the behaviour of drivers therein present particular hazards to the road user should an incident occur within a tunnel or its portal areas. The need to inform the emergency services and protect other road users demands accurate, rapid incident detection and presentation of associated information. The author discusses the detection of various vehicle hazards within a tunnel environment which has been demonstrated in North Wales. The Vehicle Hazard Detection System uses proven loop detector technology for a different application; that is, being able to monitor a continuous road section for a single stopped vehicle under light traffic flow conditions with standard, relatively inexpensive infrastructure requirements. The equipment employed is repeatable and does not require any civil engineering structures for implementation