In November 1967 the Minister of Transport and Waterways in the Netherlands asked the Institute for Road Safety Research SWOV to examine the advisable design of reflectorized registration plates from the aspect of perceptibility. Allowance had to be made for the identification of motor vehicles. especially when such plates are photographed by police and tax officials. This report gives recommendations regarding reflection. diffuse reflection, colour. Dimensions of plates and types of letters and figures. Solutions for the problem of photographing the plates are also given. A number of requirements are not given in this report. These are of a technical nature and relate to resistance to impact. bending. vibration. corrosion and the effects of petrol. And also the requirements regarding adhesion of the reflectorizing coating and securing of the plates. An interim report on a number of findings from the investigations was completed in May 1968. These findings were elucidated for government authorities during laboratory and road demonstrations. arranged at SWOV's request by the Institute for Perception RVO-TNO (Visuology Department). Soesterberg. The conclusions following the demonstration were: 1. On the basis of present knowledge it is possible to make recommendations for designing reflectorized registration plates. 2. Further research is required into the use of reflectorized registration plates. as compared with alternatives. for: a. motor vehicles in groups: making them recognizable as to categories of speed. length and width; b. individual motor vehicles: detection and estimation of differences in speed and distance. A start has meanwhile been made with preparations for the investigations mentioned in 2. For the purposes of research into design, KEMA (N.V. tot Keuring van Electrotechnische Materialen) Arnhem, made reflection measurements. A report on these is appended. The Wassenaar municipal police (Mr. G. J. Boven and Mr. J. J. Flamman) co-operated in examining the possibilities of photographing reflectorized registration plates.
Samenvatting