The relative importance of collective and individual doses from routine releases of radioactive materials to the atmosphere

Abstract Two radiological quantities, the dose to the critical group and the collective dose to the exposed population, are of interest in assessing the significance of discharges of radionuclides to the atmosphere. This paper examines two aspects of these quantities, the distance over which collective dose must be integrated to ensure that the integral has converged and the extent to which collective dose is effectively limited because of regulatory control on the dose to critical groups. For most nuclides an integration to 1000 km is shown to be adequate when assessing collective dose. Regulatory control of airborne discharges has generally limited the critical group doses to small fractions of the ICRP recommended dose limit, when the resulting collective dose is unlikely to exceed a few man-Sv. Given the costs typically involved in waste management there can be little scope for the further cost-effective reduction of airborne discharges controlled on the basis of such doses to the critical group.