Safety_Series_025_1968 - gnssn - International Atomic Energy ...

This publication is no longer validPlease see http://www.ns-iaea.org/standards/3. RADIATION PROTECTION STANDARDS3.1. G E N E RALBy 'radiation p rotection standards' is meant the whole systemo f lim its which can be set to extern al irradiation and internal co n ­tam in ation o f human bein gs so that no a p p re cia b le dam age shouldresu lt eith er fo r in dividuals o r fo r the population at la r g e .The standards recom m en d ed by the International C om m issionon R a d iolog ica l P ro te ctio n (IC R P) [13] and the IA E A B a sic SafetyStandards fo r R adiation P ro te ctio n [14] in clude both lim its to theirra d ia tio n o f the w hole body o r v a rio u s o rg a n s - th ese fo r m theb a sic standards - and p ra ctica l lim its o r standards d eriv ed fro mthe fo r m e r and rela tin g to valu es d ir e c tly m e a su ra b le o r e a sy toestim ate, nam ely the d ose fro m exp osu re to the differen t types o fradiation and the m axim u m p e r m is s ib le con cen tra tion s o f r a d io ­n u clid es in w ater and a ir .3.1.1. B asic fa cto rs in the establishm ent o f radiationp rotection standardsT o d eterm in e what irra d ia tio n le v e ls can be re g a rd e d as a c ­ceptable account must be taken of : (a) the fact that man has alwaysbeen exposed to natural radioactivity; (b) the results o f experim entsm ade on an im a ls; and (c) fin a lly , data d e riv e d fr o m hum ano b se rv a tio n .3. 1.1.1. E xp osu re to natural ra d io a ctiv ityE xposure to natural radioactivity can be broken down as follow s:external irradiation : c o s m ic radiation, radiation presentin the s o il, radiation presen t in theatm osphereinternal contam ination: 40K; 14C; Rn; R a.T his am ounts to a total value o f 100 m r e m /y r fo r the gonads,about 100 for the bone m arrow and 130 for the osteocy tes. Thus theaverage annual amount o f natural radioactivity receiv ed by the individualis of the o rd e r o f 0.1 rem .63