otherwise, the zuide for a suitable sanple (one-third the guide for the individual) is te se usel. This operational tecimique may be modifieu to meet special situations. The FRC primary numerical guides, expressed in rem, are provided in tvo reports, PAC Nos. Loanc 2, sitaarized in Table I. Seconlary numerical guides developed by FRC are expressed in terms of daily intake of specific radionsclides sorte cspoadin; to the annual W's, Consiieration is given to all radionuclides througi: all patinays to derive a total annual exposure for comparison ith FRC suides. Tlowever, for many practical situations a relatively few radionuclides yield the major contribution to total exposure; by comparison, exposures from others are very small. TABLE I FRC RADIATION PROTECTION GuipEsl/ Individual Whole body Gonads 0.5 rem/yr - Thyroid 2/ Bone marrow Bone 1.5 rems/yr 0.5 rem/yr 1.5 rems/yr Bone (alternate 2! 0. 003 pg of guide) 2262, in adult Population Group ~ 0.17 rem/yr 5 rems/30 yrs 0.5 rem/yr 0.17 rem/yr 0.5 rem/yr 0.001 ¥g of **°Ra in adult skeleton skeleton 1/ 2/ For conditions and qualifications see FRC Report Nos. 1 and 2. Based upon childs thyroid, 2 gms in weight and other factors listed in paragraphs 2.10-2.14 of FRC Report No. 2. 3/ Or the biological equivalents of these amounts of 2260p... 141-03