909 / 1778
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
Now, specification of sources is performed in terms of energy
deposition, per unit of time at a given distance:
•
in air KERMA rate [
Gy . h
-1
@ 1 m]
K
inetic
E
nergy
R
eleased per unit
MA
ss
Not used anymore