- 44 emitting radionuclides in the deep respiratory zone is 2 particles. This corresponds to a MPLB of 0.14 pCi and repre- sents a reduction of 115,009 in the existing MPLB. implies that the DF for hot particles is 115,000. This Moreover, it requires a reduction of the MPCa for Pu-239 by 115,000 to a value of 3.5x10716 uci/mi unless it is determined that the plutonium is not in hot particles. B. - Exposure of the General Public As indicated in Table II, the MPLB for non-occupational o exposure (members of the public) for occupaticnal exposure. is tenfold less than that Such an exposure limit for a hot particle would be 0.2 particles. Exposure at this level implies that on the average one out of five individuals would be contaminated by a particle and the other four would not. Obviously the exposed invididuals would be assuming a disproportionate fraction of the risk. In fact, since an. individual is exposed to whole particles, any non-occup2tional exposure to hot particles would be an overexposure. This ‘condition docs not meet the recommendations and admonitions ‘of the FRC, ICRP and NCRP. Under certain conditions, such as widespread radicac 2 contamination of the environment, the cnly data € 1 able may be related to average centaminaticn or Qn levels. Under these circumstances, it 18 necessary < make assumptions concerning the relationshis pet