Motorists drive through tunnels at high speeds. In consequence, they see the tunnel in a flash and have no idea how the tunnel looks like when they have to walk in the tunnel, for example, when evacuation is required. The authorities responsible for evacuation (and escape signs) are experts who fail to see the tunnel the way the general public does because they know too much. TNO studied how the nonexpert (the general public) reacts to signs when instructed to evacuate. The results showed that escape ways are ignored, and should be improved, for example, by making escape doors look like exits rather than access doors to technical rooms. One of the keys to improvement is a better signal-to-noise ratio, the signal being the evacuation signs - the noise all other visual stimuli including cars with flashing alarm lights. In a follow-up study, TNO investigated how motorists react to an unannounced disaster. Seven different groups of 50 cars each participated. They got stuck behind a "burning" heavy-goods vehicle that blocked the roadway. The study showed that motorists decided that the problem was a normal traffic jam, and so ignored the threat, waiting for the congestion to dissolve. This shows the need for an adequate "wake-up message" in order to start an evacuation.
Automobilisten die in een tunnel vast komen te staan achter een rokende vrachtauto, realiseren zich niet hoe riskant dat is, en blijven zitten. Het paper schetst dat ze met een kort omroepbericht in beweging gezet moeten worden en dat de vluchtwegen goed gemarkeerd moeten zijn.