Gevolgen van nieuwe vergunningplichtige grenzen voor lozingen in lucht en water door radionuclidenlaboratoria

The Dutch government has laid down new limits in the Radiation protection decree (Besluit stralingsbescherming), above which radionuclide laboratories need prior authorization for emitting and discharging radioactive substances. These new limits were needed to implement the modified system for application of the individual radionuclide approach of the Euratom-directive 96/29 to Dutch legislation. The findings reported here give us a clear understanding of the dose received by members of the public from emissions into air and water which are equal to the new limits. The report also goes into the differences between the new and the old situations. For most of the radionuclides examined, the new limits turn out to be higher than the old limits. The increase in the limits is lowest for long-lived or alpha-radiation-emitting radionuclides, and may even represent a decrease. This is especially the result of taking into account the dose-coefficient, which is usually higher for the alpha-emitters examined than for the other radionuclides. Higher emissions are allowed in the new situation for short-lived radionuclides with a low dose-coefficient because of their low contribution to dose. As a consequence of conservative assumptions in the calculation of the dose, it is expected that, in practice, the respective doses associated with the new limits of 1 and 10 radiotoxicity equivalents for emissions into air and water will exceed the dose criterion of 0,1 microsievert per year in only a few cases