Emittance Factors for Infrared Thermometers Used for Wood Products

Authors

  • Robert W. Rice

Keywords:

Emittance factor, infrared thermometers

Abstract

Most infrared thermometers and pyrometers require that an emissivity factor be set for the proper prediction of temperature. During this series of experiments, emittance values were measured for both solid wood and wood-based composites of various colors and surface textures. After establishing the correct values of emittance for the samples, temperature measurements were done at three temperature levels using two infrared thermometers. The thermometers were first tested using the suggested emissivity values from the manufacturer and then reset with the measured emittances. When compared, little difference between the temperature values measured with the infrared thermometers and the actual temperature values were found at room temperature, regardless of the emissivity setting. At nominal temperatures of 100 and zero Celsius, the differences in actual temperature and the temperature measured with the infrared thermometers were significant regardless of the emissivity settings.

References

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Published

2007-06-05

Issue

Number 4 / October 2004

Section

Research Contributions

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