Proposal of New Clearance Limits for the Safe Transport of Slightly Radioactive Materials

Because philosophy on exemption is evolving, it appears necessary to recalculate transport clearance levels on a more modern basis and to combine both types of regulations. Dose equivalent limits are presented and discussed; calculations based on the adjustement of the \"Q system\" are explained and the main results are the following : Mass activity limits should depend on radiotoxicity of nuclides Surface activity limits should concern the total activity and should be much higher than t~I present limits. A dose rate limit of 1 ~Sv.h would be interesting Clearance levels for transport should be generally higher than the other clearance levels and thus transport of slightly radioactive material would be free for most of the practices considered.