998 / 1726
Previously, source strength specification was based on
“contents”
, # of desintegrations per time unit
•
1 Ci (3.7 x 10
10
s
-1
) activity of 1g Ra-226
•
in SI-units: 1 desintegration per sec = 1 Bq
example: 1 mCi = 37 MBq
Source specification