Troxler EGauge 4590, Manual Of Operation And Instruction

Page: 123 / 186

Model 4590 9–7
S
S
o
o
u
u
r
r
c
c
e
e
D
D
e
e
c
c
a
a
y
y
The strength of radioactive material is measured by its activity,
or rate of decay. This activity decreases with time. The length of
time it takes a given amount of radioactive material to decay to
half of its original strength is referred to as the
half-life
. The
half-life of the Cs-137 source is 30 years.
The
Source Decay
function allows the operator to view how the
decrease in the radiation intensity of the source affects gauge
density measurements. It displays the actual density standard
count, the predicted standard count, and the percent difference
between the two sets of counts. The gauge calculates the
predicted standard count based upon the density standard
count at the time the gauge was calibrated and the number of
days that have elapsed since calibration.
To access the
Source Decay
function, press
〈
4
〉
at the
Extended
menu. The gauge displays:
To return to the
Extended
menu, press the
〈
ENTER/START
〉
or
〈
ESC
〉
key.
Standard After Decay
Current: ###
Predicted: ###
%Diff: ###