Measuring Method - TESTO 104-IR BT Mode D'emploi

11. Information on infrared (IR)
measurement

11.1 Measuring method

IR measurement is a visual measurement
Keep lens clean.
Do not carry out measurement with a foggy lens.
Keep the measuring range (the range between the
instrument and the measurement object) free of obstacles.
There must be no particles of dust or dirt, no humidity (rain,
steam) and no gases.
IR measurement is a surface measurement
If there is dirt, dust, frost, etc. on the surface, only the
outermost layer is measured, i.e. the dirt.
For vacuum-packed food, do not measure at air pockets.
Where the values are critical, always measure separately
with a contact thermometer. Particularly in the food sector:
measure core temperature with a penetration/immersion
thermometer.
Adjustment time
If the ambient temperature changes (change of location,
e.g. measurement indoors/outdoors), the instrument must
be allowed to equalise for 15 minutes for infrared
measurement.
11.2 Emissivity
Materials have different emission levels. This means they emit
various amounts of electromagnetic radiation. The emission
level of the instrument has a default setting of 0.95. This is
ideal for the measurement of food, non-metals (paper, ceramic,
gypsum, wood, paints and varnishes) and plastics.
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