Abstract
Tunnel evacuation modelling has shown that the public are generally reluctant to leave the perceived safety of their vehicles. Radio communications in road tunnels for emergency services has been well defined for many years but the ability of an operator to speak directly with tunnel users has traditionally required the use of emergency telephones. Public address systems that use both radio break-in and loudspeakers have been installed in a number of tunnels in recent years. This paper considers an integrated solution that exceeds the requirements of the EU tunnel directive and provides an efficient response in the event of incidents. For the covering abstract see ITRD E134653.