Reduction of BAC limit from 0.05 to 0.02 percent in Norway : effects on driver knowledge and behavior : some preliminary results.

The first hypothesis is that the new BAC limit will reduce the driving with BACs between 0.02 and 0.05 per cent. There is no change in the percentage of license holders saying that they are at least a little likely to drive with a BAC below, but not above the former limit of 0.05 per cent. Consequently the first hypothesis has to be rejected. However, the percentage claiming that they will drink no alcohol before driving has increased by 8 per cent. The second hypothesis is that the new limit will also reduce the driving with BACs above 0.5 per cent. There is no significant change in the percentage of license holders saying that they are likely to drive with a BAC above 0.05 per cent. The number of persons saying that they will drink two bottles of beer or more, i.e. the amount it takes to get to the 0.05 limit, is so small that significant changes cannot be measured by the method used in this project. Thus, the second hypothesis has to be rejected as well. The objective of the reducing driving with BACs below or above 0.05 per cent has not been achieved so far. However, the after-survey was carried out less than six months after the amendment came into effect. Another explicit objective of the amendment was "to demonstrate that driving of a motor vehicle and the consumption of alcohol do not belong together" (Odelsting Proposition 26 (1999-2000). In terms of this objective the amendment may be considered successful as the social norm of driving after only one bottle of beer has become stricter and more people claim that they drink no alcohol before driving. The most important question whether or not the reduced limit will reduce the number of alcohol-related road accidents cannot be answered by the kind of data presented in this paper, it is also too early to say. Bernhoft and Behrensdorff (2000) have shown that even if drinking and driving was reduced in Denmark by a reduced BAC limit, the number of alcohol-related accidents need not be reduced. If no reduction of alcohol-related accidents is observed in Norway, the question could be asked whether the reduced BAC limit is a necessary restriction on Norwegian drivers. (A) For the covering abstract of the conference see ITRD no 207828. The reprints are also available at the web - http://www.vti.se/pdf/reports/K18APart1.pdf; http://www.vti.se/pdf/reports/K18APart2.pdf and http://www.vti.se/pdf/reports/K18APart3.pdf.