samee ae tnt ws : tem ee ETT Peta ee . ep weet one ease oe ae Ptegee oat e ~ 45 - average and maximum doses. The Federal Radiation Council sugyests the use of the arbitrary assumption that the majority of individuals do not vary from the average by a factor greater than three. Thus, we recommenc ‘ne use of 0.17 rem for yearly whole-body exposure tI average population groucs. (It is noted that this cuide is also in essential agreement with current rocommendations of the NCRP and the ICRP.) It is critical that this guide be apolied with reason and judgement. Especially, it is noted that the use of the average figure, as a substitute for evidence concerning the dose to individuals, is permissible only when there is a probability of aspreciable homogeneity concerning the distribution of the dose witnin the population included in the average. /? Strict adnarence to these guidelines implies that the ambient air standard snould be zero particles, 99 'd While a variety o ro suggestions could be pro osed, we recommend a slight deviaczion from tnese guidelines and the acceptance of the Gisproccriionate risk implicit in the 0.2 varticla standareé. This is a workable solution since best estimates ef lung burdens can be fractional quantities. Thus, we recommend thai tn= MPLP3 for menbers of the sublic be 0.2 N ~~ ~ Gg t= it 0 Go he u a 1f ~ (D 'g oO i oy cy km fu Ou ' 2 tt ry tg etoal wm ‘f9 public be 0.97 ot particles, a factor of 3 less than the rd on a 1/10,909 risk per “W933 would have would not 2xist. b2an ons ome ao we