© Thermoteknix Systems Ltd 2020
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8.1.1
Setup the Alarm Threshold value
Next an appropriate alarm threshold should be entered. Selecting an appropriate
value threshold is not an exact science because of the variability and range of human
skin temperature and ambient conditions. Too high a threshold and a feverish person
may not trigger an alarm. If the threshold is set too low then the system will trigger
on subjects with normal temperatures and not a raised skin temperature.
The objective is to set the threshold so that almost all subjects with abnormal
temperatures that might indicate the presence of a fever are detected. This will
inevitably generate a number of false alarms but these can be quickly discounted
using a quick otic temperature measurement. A threshold of 37°C could be usefully
selected as a starting threshold but adjusted according to local conditions.
When an alarm is triggered a red circle is overlaid on the screen to indicate the
position of the pixels that actuate the alarm. This will identify the subjects who
need secondary testing with an approved clinical thermometer. As temperatures
approach the alarm threshold it is sometimes possible for alarm activity shown by red
pixels to appear at a number of different locations.
Rather than displaying a multitude of red alarm circles FevIR Cam Software uses
integral proprietary algorithms to assess active alarm conditions for a locale within
the image and draws a red circle of appropriate radius. This enables the operator to
assess the severity of the alarm threshold condition more accurately.
