RayTek MARATHON MM SERIES User Manual

Appendix
Marathon MM Rev. D7 Jul 2017 87
NON-METALS
Emissivity
Material
1 µm
1.6 µm
2.3 µm
5 µm
7.9 µm
8 – 14 µm
Asbestos
0.9
0.8
0.9
0.95
Asphalt
0.95
0.95-1.00
0.95
Basalt
0.7
0.7
Carbon
Unoxidized
0.8-0.95
0,8-0,9
0.8-0.9
0.8-0.9
Graphite
0.8-0.9
0.8-0.9
0.7-0.9
0.45-0.70
0.7-0.8
Carborundum
0.95
0.9
0.9
Ceramic
0.4
0.8-0.95
0.8-0.95
0.95
Clay
0.8-0.95
0.85-0.95
0.95
Coke
0.95-1.00
0.95-1.00
0.95-1.00
0.95-1.00
0.95-1.00
0.95-1.00
Concrete
0.65
0.9
0.9
0.95
Cloth
0.95
0.95
Glass
Plate
0.2
0.98
0.98
0.85
“Gob”
0.4-0.9
0.9
Gravel
0.95
0.95
Gypsum
0.4-0.97
0.8-0.95
Ice
0.98
Limestone
0.4-0.98
0.98
Paint (non-al.)
0.90-1.00
0.9-0.95
Paper (any color)
0.95
0.90-1.00
0.95
Plastic, opaque at 500
µm thickness (20 mils)
0.95
0.95
Rubber
0.9
0.95-1.00
0.95
Sand
0.9
0.9
Snow
0.9
Soil
0.9-0.98
Water
0.93
Wood, Natural
0.9-0.95
0.90-1.00
0.9-0.95
Tab. 14: Typical Emissivity Values
To optimize surface temperature measurements, consider the following guidelines:
 Determine the object emissivity using the instrument which is also to be used for the
measurements.
 Avoid reflections by shielding the object from surrounding temperature sources.
 For higher temperature objects use instruments with the shortest wavelength possible.
 For translucent materials such as plastic foils or glass, assure that the background is uniform
and lower in temperature than the object.

RayTek MARATHON MM SERIES Specifications

General

Brand	RayTek
Model	MARATHON MM SERIES
Category	Thermometer
Language	English