The RETRACT study was sponsored by the Department of the Environment, Transport and the Regions (DETR), to investigate how transport telematics technologies could provide flexible solutions to predicted air pollution episodes in urban areas. This paper presents the results of a systematic attempt to bring together the experiences from isolated research studies and field trials of pollution-responsive telematics applications. Part IV of the Environment Act 1995 addressed air quality issues, and identified the need for a National Air Quality Strategy, whose first draft was published in 1996. The Strategy aims to establish air quality standards, set targets to limit airborne substances, and requires local authorities to produce Air Quality Action Plans (AQAPs). RETRACT identified eight main telematics-based measures that could be operated to respond to pollution: (1) traffic signal control; (2) traveller information provision; (3) traffic re-routing; (4) variable speed control; (5) variable high-occupancy vehicle (HOV) and bus lanes; (6) variable parking pricing; (7) environmental road pricing; and (8) environmental access control. Each type of measure could be implemented in UK urban areas to operate normally for most of the time, but switch to `pollution-responsive' mode during a predicted air pollution episode.
Samenvatting