GE RSDetection RS-S131-200-ER0000 - Sample Calculation

RSDetection
User’s Manual
March 2016 S131-200-UM Rev A
Page 56
g
6.4.1 Sample Calculation
1. Calculate the Exposure Rate at a distance “D” from Co
60
source ‘t” years after
source certification:
49.1uR/h =
E
0.63* 0.982* 0.07475* 1062uR/h =
E
e
*
e
*
365.8
100
1062uR/h =
E
K
*
e
*
D
100
*
E
=
E
uR/h 1062 =
E
1920days)5.26years( = T
)1230.8days3.37years( = t
cm)feet(365.8 12 = D
12
12
/5.26)0.693(3.51-5(265.8)-6.8E-
2
12
d
100)-(D
2
10012
100













1. Sensitivity of the sensor at distance “D” from Co
60
source:
D
EXPOSURE
RATE
P+S+A
S+A
P
k(Co60)
Feet
cm
R/h
amps
amps
amps
amps/R/h
12
365.8
202.8e-6
-6.124e-12
-1.403e-12
-4.722e-12
-2.328e-8
K = [(P+S+A) – (S+A)] / Exposure Rate
k = [-6.124e-12 – -1.403e-12 ] / 202.8e-6 R/h
k = -2.328e-8 amps/R/h
2. Calculate the average sensitivity. In a typical calibration, the following values of k
might be calculated:
D
k
Feet
cm
amps/R/h
12
366
-2.328e-8
14
427
-2.335e-8
16
488
-2.336e-8
18
549
-2.333e-8
Average(
k
)
-2.333e-8
3. Calculate the standard deviation σ = 3.6e-11.