Can the use of road safety measures on national roads in Norway be interpreted as an informal application of the ALARP principle

Abstract The ALARP principle, stating that risks should be reduced to a level “As Low As Reasonably Practicable”, is widely known and discussed in risk management. The principle is flexible, as the interpretation of the key concepts of reasonable and practicable can be adapted to different contexts. This paper discusses whether the use of road safety measures on national roads in Norway can be interpreted as an informal application of the ALARP-principle. According to official guidelines, priority setting for major road investments should be based on cost-benefit analysis. Most road safety measures are low-cost projects that have traditionally not been subject to cost-benefit analysis. A use of these measures regarded as reasonable in the ALARP sense may include considerations of cost, efficiency and fair distribution. Data on 328 road safety measures implemented around 2000 is used to evaluate factors influencing their use. It is argued that the use of these measures is consistent with an informal application of the ALARP-principle.