Lc Table I. - (Continued) Per cent abundanceat: 1) Fission One One One Ten products week month year years Relative MPC Half life?) values?! Bal40 g.8 10.8 --- -=-- 13 days 300 Lal4d 9.4 12.5 --- --- 40 hours 200 Ce 144 --- 2.0 26.5 --- Pri44 --- 2.0 26.5 --- Pmi47 --- --- 5.7 15.8 285 days 100 17 mins. * 950 days 2, 000 Mn°?4 290 days 1, 000 Feo 950 days 8, 000 Fe59 45 days 600 Cod? 270 days 5, 000 Co58 71 days 1, 000 Co6E 1900 days 500 zn®5 245 days 1, 000 Nor-fission products 1) Hunter and Ballou (1951) 2) Strominger, Hollander and Seaborg (1958) 3) MPC values relative to Sr99; based upon values from Handbook 69 for which MPC for Sr90 ig 107Sye/cec * A short-lived daughter for which hazard is negligible in comparison to hazard for parent