’ natural backeround and medical procedures ar2 apniied to Neon? and FRC reco-mendations. ICRP developed the concept of “acceptable risk." Unless nan vishes to dispense with activities involving exposures to fonizing radiation, he must recomnize that there is a iesree wi cish and suse Linit the raltacion tt x Ghia ui e , be ( Patt ot. Liudeaci.a. ws tule tr dose to a level at «mich the assumed risk is deemed to be acceptable to activities. Tor planned or controlled exposures of individuals and populations, the ICR? has recommended the term "dose limit." Recommended dose limits are Shousit to be iwsoeciate! vith a very low decree of risk. Te Tor unplannel exposures from uncontrolled sources the term "action level" is recommended. In general it will be appropriate to institute countermeasures only when their social cost and risk will be less than those resulting from the exposure. Setting of action levels is the responsibility of national authorities. It is not desirable to exposure members of the public to doses as high as those considered to be acceptable for radiation workers because children are involved, members of the public do not make the choice to be exposed, and members of the public are not subject to selection, supervision and monitoring, and are exposed to the risks of their oim occupations. For planning purposes , dose linits for members of the public are set a factor of ten below those for radiation workers. pms 114-05