Occupational radiation exposure in Switzerland: Novel dose limit of 20 mSv/a proves to have positive effects

Personal dosimetry in Switzerland has been experiencing essential advancement during the last twenty years in terms of fundamental concepts, technical aspects, and quality. The measured results show considerable reduction of collective doses and personal doses, indicating a clear improvement of radiation protection. It is expected that the novel dosimetry regulation together with the radiation protection ordinance will be a suitable basis to continue this trend and to achieve further improvements with respect to incorporation monitoring, where the ''triage'' measurements performed under the responsibility of the plant operators will become official procedure, so that incorporation measurements by an authority or official office will be prescribed by the law only in cases exceeding official limits. There is still need for improvement in neutron dosimetry, although the number of persons to be monitored as well as the doses measured are small. Approval and application of electronic dosemeters as ''official'' instruments are likely to represent the most essential step forward in the near future, so that despite the given high quality level in dosimetry, changes to the better are due to come. (orig.)