Chernobyl experience in field of retrospective dosimetry: Reconstruction of doses to the population and liquidators involved in the accident

Evacuees from the 30 km zone and liquidators are likely to have received the highest Chernobyl exposures. Doses to the majority of them remained unknown, calling for dose reconstruction. This need prompted development of new techniques of retrospective dosimetry. Application of state-of-an stochastic dosimetric models and determination of site-specific location factors allowed the determination of individual doses and uncertainty ranges for a significant pan of the evacuated population. A number of approaches were used to recover existing gaps in dosimetric information related to liquidators. EPR dosimetry with teeth is useful for high precision retrospective dosimetry of liquidators; now teeth from liquidators are being collected systematically in Ukraine. Analytical dose reconstruction was conducted for about 2000 Chernobyl workers. Reconstruction of doses to the rest of the liquidators requires application of a different methodology based on analysis of regularities of exposure and assignment of dose intervals according to attributes of the liquidators.