TABLE 4-4. RADIOACTIVE STANDARD SOURCES Source lsotope(s) Serial Number Reference Date Base Decay Material (dpm) Calibration _Purpose_ Elec troplated Dises (SS = stainless steel; Ni = nickel) 0c 905,90y S-1447 s-7668 5-5-77 5-9-77 Ss Ni 0.0049 + 0.0002! 16,420 + 490 Gamma spectrometer Beta counter 90,90 5~-1510 6-10-77 Ni 3,060 Beta counter 90580y 905,90y 230» 235) + 96 s-1914 s-1915 S-10764 S-1508 11-9-78 11-9-78 6-10-77 6-10-77 Ni Ni ss SS 1,320 1,700 1,630 1,250 + + + + 40 90 30 25 Beta counter Beta counter Alpha counter Alpha spectrometer 2365), S-1513 6-10-77 $s 8 20 + 20 Alpha spectrometer Mixed 8-151] 6-10-77 8S 3,760 + 80 Gamma spectrometer 239 bu S-1509 6-10-77 Ni 4,040 + 80 Alpha spectrometer S-7669 5-9-79 Ni 4,150 + 80 24) ay 241 am S-7680 6-10-77 Ni 1,260 + 25 Alpha spectrometer Alpha spectrometer Solutions 0G 7-1-76 2,904/ml Gammasystems I33R0 7-1-76 13,928/ml Gamma systems ISTE. 5-1-76 13,159/ml Gamma systems Internal tracer® 1S2py 4-16-77 444,000/ml 236 p,, 7-2-78 5.17/ml 239p, Mixed? 1281 4332 Gamma systems 10-1-76 Sept. 74 99.42 + 1% 134.5 + 1.4% Prepare spikes Internal tracer 6-1-74 2,434/ml Gamma and spikes 133R4 9-19-78 12,079/ml Gamma systems 241 ay 9-19-78 2,417/ml1 Gamma systems 241 am au & os NM he Petri Dishes (coral base) Unit is pCi rather than dpm. Source included 237Np, 38pu, and 239Pu, Used NBS 239Pu standard 1281 to cross-calibrate 286py, Alpha emissions pet second per gram of solution. From NBS. Source included 229Np and 243Am. Aetivity ratio of 241Am to 243am was 0.002. Nuclear transformations per second per gram. From NBS. 129