Trivial risks and the new radiation protection system.

The International Commission on Radiological Protection proposes that doses below a certain level should be excluded from the system of protection, without regard to the number of people exposed. As the Commission assumes that there is a risk of harm even from very low doses, the proposal also disregards these very low risks. The arguments for this proposal are examined here. It is argued that the fact that risks are small compared to natural sources cannot be used as justification for accepting them. The principle 'if the risk of harm to the health of the most exposed individual is trivial, then the total risk is trivial--irrespective of how many people are exposed' is analysed. It is found to equivocate on the meaning of the word trivial and to ignore the total risk. It is also argued that the new proposal is not justified by a change from a utilitarian ethic to an ethic based on individual rights. Finally, it is suggested that small doses should only be disregarded if the expected value of harm is small, and the exclusion level should thus depend on the number of people exposed.