In 1977, the Dutch Government selected two urban districts for an experiment with traffic controls aiming to reduce the disruption of living conditions. This paper summarises the effects of later reconstruction of the traffic zones to improve road safety and traffic flow. It compares the study periods: (1) 1972 to 1977, before these measures were introduced; (2) 1982 to 1986, after they became fully effective. Control zones were selected to establish the impact of trends. The accident study aimed to measure effects in terms of changesin the numbers of road accidents with casualties, and considered three groups of accidents, involving: (1) no motor vehicles; (2) motorvehicles only; (3) both motor vehicles and other road users. The following conclusions are drawn: (1) creation of residential areas seems to reduce injury accidents less effectively than cheaper measurescurrently recommended in zones with a 30 kph speed limit; (2) 30 kph zones are safer, have lower speeds and less through traffic, and keep their residents happy; (3) main roads function better with good facilities for through traffic; (4) access roads to an urban district do not function well if used by through traffic.
Abstract