PREDICTION METHOD OF WET BULB TEMPERATURE AND WBGT, WBGT METER, AND HEAT STROKE RISK DETERMINATION DEVICE

PROBLEM TO BE SOLVED: To solve the problem wherein measurement of WBGT (Wet-Bulb Globe Temperature) requires measurement of a wet-bulb temperature and a black-bulb temperature. SOLUTION: A wet-bulb temperature is calculated numerically by adopting a relative humidity and an air temperature as variables by using a psychrometer formula, and function fitting is performed by polynomial approximation using a least-squares method, to thereby generate an approximation prediction expression of the wet-bulb temperature. Then, the wet-bulb temperature is approximated and predicted by substituting measured values of the relative humidity and the air temperature for the approximation prediction expression, and further an approximation prediction expression of the WBGT is generated by performing quadratic approximation from a relation between a wet-bulb temperature prediction value and the air temperature, and the wet-bulb temperature prediction value and the measured value of the air temperature are substituted for the approximation prediction expression, to thereby approximate and predict the WBGT. According to a heat stroke risk determination device 1 using this method, since the wet-bulb temperature or the black-bulb temperature is not measured directly, the size/weight and cost can be reduced, and handling is simplified, and a risk can be obtianed quickly by display on a display 5, lighting of a lamp 7 or rumbling of a speaker 13, and consequently the device 1 is suitable for a widespread type. COPYRIGHT: (C)2011,JPO&INPIT