~ 50 - the value selected by Kathren be used when the RF is unknown to determine the ambient ground contamination standard. Applying an Rr=ic74 m71 to the ambient MPCa standard recommended in the previous section, we obtain a maximum pere missible surface contamination of 9x1078 uci/m. 86 (MPSC) ; This is roughly 1 hot particle/m. In areas where an RF greater or less be shown to apply, E, level for hot particles than 1074 m1 could the MPSC could be altered appropriately. As Low as Practicable Hearinas It is to be understood that the above recommendations do not represent Sndorsement on our part of the risk inherent in the existing radiation protection guidelines upon -which these recommendations are based, Rather, we offer the admonition that the exposures should be kept as far below these guidelines as is practicable. Therefore, we further recommend that these guidelines be incorporated into the existing regulations without’ delay and that the appropriate agency or agencies convene hearings to determine for the regulations what constitutes as low as practicable limits for exposure to hot particles. 86/ This value is derived as follows: for hot particles is 9xl07 18 The recommended MPCa uci/ml which corresponds to 9xl0712 uci/m3. The maximum ground contamination level, using RF=1074 m-1, is 9x10712/10-4 = 9x10-8 uCi/m2. wate uy . M4 ald etd soho ae “i tp 3 7. 3 i: ’ Ne vos °- . ce Maite ’ aennE ae Ww Sey ey * “he io : - } Ae rua a: at. ‘+ ae - ‘ y ase oo an “a6 ot4 ye . at ‘he? pee? the. * i : .