Kentekening caravans en aanhangwagens : een onderzoek naar parkcijfers en een enquête onder eigenaren van caravans en aanhangwagens. In opdracht van Rijksdienst voor het Wegverkeer, Centrum voor Voertuigtechniek en Informatie.

Registration numbers for caravans and trailers : a study of vehicle stocks and a survey of owners of caravans and trailers. From February 1st 2002, trailers (or semi-trailers) and caravans with a mass of more than 750 kilograms must have a registration number. For RDW Vehicle Technology and Information Centre, SWOV has determined how many trailers and caravans require a registration number and to what extent owners are willing to apply for a registration number. The number of owners possessing a registration certificate which belongs to a (semi-) trailer or caravan heavier than 750 kg also had to be determined. The necessary data for answering the research questions was obtained in two ways: - personal interviews with various organisations (Central Bureau of Statistics, trade organisations, etc.) to determine the vehicle stocks in 2002; - a written survey of owners, with questions about the willingness to apply for a registration number, possession of a registration certificate, and the number of kilometres travelled. For answering the RDW questions, only the results for caravans and trailers heavier than 750 kg. were relevant. The object was to make the best estimate that was then possible. On account of the method used and the statistical margins the estimates can differ from the real numbers. The estimate for the number of caravans heavier than 750 kg. in 2002 is 405,000. For trailers between 750 and 3,500 kg. and those heavier than 3,500 kg. the estimates are 206,000 and 152,000 respectively. About 4% of the owners of a caravan heavier than 750 kg. do not have a registration certificate. For the lighter and heavier trailers this is 16% and 3 % respectively. About 97% of the owners of a caravan heavier than 750 kg. will apply for a registration number. For both weight classes of trailers this is 96%. SWOV was concerned about the risks of driving with a trailer, but especially with a caravan. The survey of trailer and caravan owners made it possible to (also) ask questions about kilometres travelled per year, accidents, and safety inspection. For the time being, SWOV considers this data as basic data that is useful for other SWOV research.