Mirion Technologies GEM-5 User Manual

Chapter 7 Retrieving Information
262
Table 16 Column Label Description
Term
Description
Eff: The zone efficiency.
Result:
The monitoring decision for the detection zone (“Clean”, “Contaminated”,
“*Contam” or “Skipped”).
Gamma Alarm Test Points
Rb: Bkg (Rate) x Self Shield Factor
Tb: Background averaging time for Bkg (Rate).
ALS (Rate): “Alarm Level Setpoint”, defined in
High:
High Activity; enabled when High Contamination Alarm in is set to “Enable (High
Alarm Activity)” in the F1 – Common Values screen (on page 105)
CTP (Rate): “Contaminated Trip Point”, defined in Equation 27 on page 287.
ATP (Rate): “Alarm Trip Point”, defined in Equation 28 on page 287.
LLD (Rate): “Lowest Level of Detection”, defined in Equation 25 on page 286.
Equiv:
Alarm release limit that would give ATP = LLD in the fractional count time
seconds (not the rounded up integer seconds). This is an indication of the
sensitivity margin for the zone.
Used (s):
Actual counting time, including extended count time and total time for counting
feet, Gamma body, Gamma shoe, or items, or head (if Position=2 and counting feet
or Gamma body, etc. in two-steps).
Calc (s):
The count time required for ATP = LLD (from Equation 29 on page 289)
Gamma Statistics
Sum Ratio Ratio of the smallest to largest Net Count Rate for detector sections in the zone.
Gross (s): Gross count time
Gross
(Rate):
Gross count rate (Raw/Live)
Gross Var
Variance of gross count rate (similar to Equation 20 on page 277 but applied to
occupant collection).
G Var Ratio
Variance Ratio of gross count rate (similar to Equation 21on page 277 but applied
to occupant collection).
Gross (N)
Number of readings in Gross rate.
Bkg (s)
Time in background average.
Bkg (Rate):
Average background count rate for the zone (called R
B
in the Algorithms appendix,
Alarm Settings and Strategy on page 285).
Bkg Var
Variance of background rate per Equation 20 on page 277.
B Var Ratio Variance Ratio of background Average per Equation 21on page 277.
Bkg (N) Number of readings in background average.
Net (Rate): Net count rate = (Gross Rate – Bkg Rate x Self Shield Factor)
Activity Net Rate / Efficiency

Mirion Technologies GEM-5 Specifications

General

Brand	Mirion Technologies
Model	GEM-5
Category	Monitor
Language	English