Hioki 2D THERMO HiTESTER, Instruction Manual, Page: 64 / 70

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Chapter 7 Maintenance and Service
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Substance Thermal
emissivity
Substance Thermal
emissivity
Asphalt 0.90 to 0.98 Charcoal
(powder)
0.96
Concrete 0.94 Lacquer 0.80 to 0.95
Cement 0.96 Lacquer (matt) 0.97
Sand 0.90 Rubber (black) 0.94
Earth 0.92 to 0.96 Plastic 0.85
Water 0.92 to 0.96 Timber 0.90
Ice 0.96 to 0.98 Paper 0.70 to 0.94
Snow 0.83 Aluminium
oxides
0.76
Glass 0.90 to 0.95 Chromium
oxides
0.81
Ceramic 0.90 to 0.94 Copper oxides 0.78
Marble 0.94 Iron oxides 0.78 to 0.82
Fluorite 0.30 to 0.40 Nickel oxides 0.90
Plaster 0.80 to 0.90 Titanium
oxides
0.40 to 0.60
Mortar 0.89 to 0.91 Zinc oxides 0.11 to 0.28
Brick (red) 0.93 to 0.96 Brass oxides 0.56 to 0.64
Textiles 0.90 Uneven
bronze
surfaces
0.55
Cloth (black) 0.98 Rolled
stainless steel
0.45
Human skin 0.98 Heavily rusted
iron
0.69
Leather 0.75 to 0.80
7.3 Emissivity Table
When the emissivity of the object is low, the
readings may become unstable. In that case, use the
blackbody spray or blackbody tape available as
optional equipment.
Use the table below as a guide. Emissivity varies
depending on the smoothness of the surface and the
thickness of the material besides the material itself.