Setting standards for trivial concentrations of radioactivity

The ICRP system of dose limitation implies that a level of radioactivity exists below which the material should be considered for properties other than its radioactivity. The need for agreement on this trivial level or concentration of radioactivity is discussed. The basis for the choice of a trivial dose was discussed in relation to the variation in natural radiation dose (4-400 mrad/annum) and also to the comparison of risks from other natural causes. A value of 10 mrad/annum is proposed as a trivial dose to the individual. The application of the trivial dose when considering the disposal of radioactivity waste is discussed. An annual dose commitment of 0.1 mrad is proposed. To ensure that the dose commitment from future practices will not accumulate and exceed the trivial dose, the application of a specific activity approach may prove valuable for setting trivial concentration levels to radioactive wastes. (UK)