Two driver alerting devices installed on the approaches to hazardous roundabout sites in Wiltshire have been compared. One of these devices known as rumble areas produces both an auditory and visual signal whereas the other device, consisting of a grid of yellow bars, produces essentially visual cues. The covert response has been examined in a total of twenty-five subjects using subjective assessments, and in the case of nine subjects, heart rate responses in addition. Results of the heart rate tests indicate that rumble areas generally increased levels of alertness although there was no significant support for this from the subjective assessment. Yellow bars did not appear to have a similar effect. The devices did not alarm subjects and although both tended to slightly increase levels of distraction the resulting level was still low. (Author/publisher)
Samenvatting