© Thermoteknix Systems Ltd 2020
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the FevIR Cam factory pre-calibration to ensure ± 0.2°C accurate temperature
measurements.
The Calibration Reference Source is set to a midscale value of 35.0°C. Unlike the
internal body temperature which is very carefully maintained by the body at 37.0°C
(98.4°F), skin temperature is usually lower than internal body temperature and
varies with many factors, but typically will also be raised in the presence of fever.
A common consideration is that head temperature is generally 2.0°C lower than
core body temperature, except over the inner aspect of the orbit of the eye (eye
socket, closest area to the nose). The area around the inner aspect of the orbit is
served by a small artery which is just below the surface and this provides a close
approximation to core (inner) body temperature. This is a better indicator of
core temperature than the forehead which can have a raised surface temperature
due to many non-fever causes, whereas the temperature of the inner aspect of
the orbit is much more closely related to fever temperatures.
The ambient temperature will have a significant effect and you may want to change
this value higher or lower, depending on predominant skin temperature values
obtained in the location of use.
7.3
Scanning Area (Setup menu, F7)
The second region to be defined is the Scanning area. This is outlined by a white
rectangle and should be positioned to enclose the screen area in which target
subjects will be monitored. A high temperature threshold (typically set above 45°C)
will exclude any objects at this temperature or above from the Scanning area
measurement. This is to ensure that any hot objects (lights, coffee cups,
transformers etc.) do not trigger the monitoring region alarm.
Use the mouse cursor on the boundary to change the area size, hold the left mouse
button down anywhere inside the area to move the whole area from place to place.
Do not include the Calibration Reference Source heated reference area within the
area to be scanned; left click and move it to the desired position.
