Low Temperature Thermometer
RT8B
User Guide
13
EMISSIVITY
7
In order to obtain accurate temperature measurements, the emissivity value of the
target surface must be known. This section of the
RT8B
Thermometer User Guide
contains typical emissivity values of the most commonly measured materials. Where
no emissivity value is quoted, this means that either the thermometer is not suitable
for the measurement application or the temperature of the target is outside the
thermometer’s measurement span. If you have a query regarding the emissivity
of the target in your measurement application, contact AMETEK Land Instruments
International for assistance.
7.1 Refractories
Refractories
Material
Emissivity Value
Magnesite
oxidised
0.60
0.85
Brick
Red
0.90
White
Refractory
0.80
Silica
0.80
Sillimanite
0.60
Ceramics
0.90
Alumina
0.60
Fig. 10 Typical Emissivity Values for Refractories
