_— ALENDIL£ tyeeds B) The following (data are abstracted fror exrne-inertal results, wherein a thin pee source prepared by soaking a f‘iter paper in a solution of phosphetes, alloving !t to ¢ry, and then meas.ring surface dose rates with a evurfece ionisation charber.? Thiekness of source 9.6 rg/cx* Activity af source 77.0pe/oxt Surface dose rate ~ 0.127 rep/sec 457 Dosage rate at derth of x certinaters reps/hr e79-5x &. Ipeoretically UsingtheequetionfroxApreniixBP Re 22eTR (por 33°) Substituting above datas R 2 9.5 Roe ~(9,5)(0.907, , 4, a4 . a 27,90 C repa/hr Let C © 77) asc/ex* Fo g Then Re 7) x 77 . © 539 reps/hr at 7 meer ey 732) ffir le, Tacwon E. leGrawill Fook “7