Protective actions in the late phase--intervention criteria and decision-making.

Major countermeasures in the late phase of a nuclear or radiological accident where long-lived radionuclides have been dispersed in the environment are relocation/resettlement, foodstuff restrictions, agricultural countermeasures and clean-up of contaminated areas. There has essentially been a broad acceptance internationally of the principles for their introduction, but it has not been possible to reach an agreement for the purpose of defining a net benefit based upon the exact weighting to be attached to each of the attributes influencing the decision on intervention, e.g. socio-psychological attributes. Optimisation of protection, i.e. maximising the net benefit, is not a question of developing radiation protection philosophy to fully include socio-psychological factors but rather to include these factors--in parallel with the radiological protection factors--in cooperation between radiation protection experts and e.g. experts in social and psychological sciences under the responsibility of the decision-maker, who will take the final decision on the introduction of long-term countermeasures.