I-CAM 380/I-CAM 640 P-SERIES USER MANUAL
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All objects radiate infrared energy. The amount of energy radiated varies based
on the actual surface temperature and the surface emissivity of the object. The
Thermal imager senses the infrared energy from the surface of the object and
uses this data to calculate an estimated temperature value.
Many common objects and materials such as painted metal, wood, water, skin,
and cloth are particularly good at radiating energy and it is easy to get relatively
accurate measurements. For surfaces that are good at radiating energy (high
emissivity), the emissivity factor is >=0.90. This simplification does not work on
shiny surfaces or unpainted metals as they have an emissivity of <0.6. These
materials are not good at radiating energy and are classified as low emissivity.
Material
Emissivity
Water
0.36
Stainless steel
0.14
Aluminum plate
0.09
Asphalt
0.96
Concrete
0.97
Cast iron
0.81
Rubber
0.95
Wood
0.85
Brick
0.75
Tape
0.96
Brass plate
0.06
Human skin
0.98
PVC plastic
0.93
Polycarbonate
0.80
Oxidized copper
0.78
Rust
0.80
Paint
0.90
Soil
0.93
SURFACES WITH AN EMISSIVITY OF < 0.60 MAKE RELIABLE AND CONSISTENT
MEASUREMENTS PROBLEMATIC. THE LOWER THE EMISSIVITY, THE GREATER
POTENTIAL FOR ERROR WITHIN THE DEVICE’S CALCULATIONS. ERRORS MAY
STILL OCCUR EVEN WHEN ADJUSTMENTS ARE PERFORMED PROPERLY.
The following table gives typical emissivity of important materials:
