Evaluation of the Applicability of Infrared and Thermistor-Thermometry in Thermophysiology Research

The accuracy and reliability of temperature measuring devices in thermal physiology research and clinical practice has been subject of various investigations. Research data have been conflicting in some cases. Further investigations are therefore needed to elucidate the reliability and sensitivity of these devices under different temperature settings. The aim of this study was to evaluate the reliability and sensitivity of the tympanic thermistor (TT), infrared tympanic thermometer (ITT) and oral thermistor (OT) in the detection of body temperature changes in adults exposed to heat load. A single set of three simultaneous temperatures i.e. oral, left and right tympanic membrane were measured. At rest, core temperature (Tc) measured by TT was 0.45℃ and+0.10～-0.12℃ (changed range) higher than that measured with OT and ITT respectively. At the end of 30min 43℃ water bath leg immersion, Tc measured by TT was 0.48℃ and 0.04℃ higher than that measured with OT and ITT. This showed that when subjects were exposed to heat load, there was no difference in Tc measured by TT and ITT, although both were significantly higher than that measured with OT. From these results, it might be thought that the sensitivity for Tc detection increased in the order tympanic thermistor>infrared thermometer>oral thermistor. Further-more, in addition to the merits of infrared thermometer, the hazards and difficulties of tympanic temperature measurement were discussed from the view of development of the various kinds of thermometers