7
5 EMISSIVITY
The intensity of infrared radiation which is emitted
by a body depends not only upon the
temperature of the body, but also upon the ability
of the surface of the body to emit infrared energy.
This ability of the surface of the body to emit
infrared energy is characterised by a factor
known as the ‘emissivity’ of the material.
Your
Elcometer
214L
Infrared
Digital
Thermometer has a pre-set fixed emissivity value
of 0.95; this value is very common for most
organic materials and painted or oxidised
surfaces.
The fixed emissivity value of 0.95 is shown in the
bottom right hand corner of the display.
6 HINTS AND TIPS
• Shiny or metallic surfaces may result in
inaccurate readings. To prevent this, cover
the measuring surface with either matt black
paint or with a suitable tape. Remember to
leave extra time for the surface covering to
reach the temperature of the body being
measured before taking a reading.
• Infrared thermometers cannot measure the
temperature of objects through transparent
materials such as glass or plastic.
• Always keep the lens clear of steam, dust,
smoke or other particles which would
otherwise cause inaccurate measurement.
Temperature
Infrared energy
1
Emissivity
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214L_TMA-0379-00-02 19623.fm Page 7 Thursday, October 16, 2008 3:34 PM
