What is a reasonable cost for protection against radiation and other risks?

In Sweden, the National Audit Bureau is encouraging attempts at discussing the costs of protection. For many years, a government authority considering new regulations must provide the government with background material illustrating the costs, the expected benefits, and other aspects of the decision. Direct costs should be stated together with nonquantifiable factors indicated by a valuation of whether their consequences are positive or negative. Applied to radiation protection, this includes discussion of the resources worth spending in order to prevent a case of serious radiation injury. If the marginal cost for a protective measure is < 5 million Swedish crowns (5 MSEK: approximately 1 million U.S. dollars) per prevented case, the radiation protection authority considers the measure to be strongly justified. If the cost exceeds 25 MSEK per case, then very strong reasons are required for implementation of the measure. In the intermediate interval, measures are particularly justified if the marginal costs are in the lower end and the total societal cost of the protection is of little concern at the national economical level. The interval 5-25 MSEK per case corresponds to 0.4-2 MSEK person-sievert-1. Resource allocation for health protection in general, ethical aspects, and practical difficulties in assessing costs and risks are briefly discussed in the paper. Priorities in Swedish radiation protection are presented and a case study for the use of carbon fiber cassettes in x-ray diagnostics is given as an example.