40293 7 TABLE I Factors for Converting Air Concentrations of Radioiodine to Thyroid Dose via Inhalation* (mrem/yrper pCi/m?) Age I-129 1-130 I-13) 1-132 I-133 1-134 1-135 Tyr 20.8 2.22 20.4 0.250 5.05 0.0637 1.12 4 yr 10.7 1.2] 10.6 0.135 2.59 0.0343 0.598 14 yr «(17.5 0.880 0.0824 1.91 0.0237 0.413 Adult 36.3** 1.01 0.109 1.99 0.0273 0.471 * 8.53 10.4 Breathing rates assumed: 1-year old, 5.6 m3/d; 4-year old, 7.0 m3/d; 14-year old, 13.5 m3/d; adult, 20 m3/d. Organic and inorganic forms of radioiodine give the same dose via inhalation. ** Dose in first year. Maximum dose rate after equilibrium is reached between thyroid burden and intake rate would be 1.09 times this value. Revised May 1976 . To change ty and t for short half-life radioiodines per ICRP Publ. 10.