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LAWRENCE R. PROUTY AND JAMES D. HARDY 



complished by means of two black bodies (Leslie cubes) at different 

 temperatures. Two Leslie cubes are employed in order to rule out 

 the necessity of measuring the temperature of the thermosensitive 

 elements of the radiometer {29,30). 



3. Applications of Radiometers 



Radiometers have been extensively used in the measurement of 

 skin and surface temperature. An instrument of this tyi^e is shown 

 in Figure 14. The latter measurement is of particular importance 



Fig. 14. Hardy dermal radiometer. (Courtesy Baird Associates.) 



in bioclimatology. The radiant temperature of the nighttime sky, 

 the terrestrial surroundings, and the sun are all of importance in 

 evaluating thermal stress. Experimental investigations of the sensi- 

 tivity of the human skin to temperature and to pain have involved 

 the use of radiometric techniques as skin thermometers. As can be 

 seen from Table I, there is no other instrument as dependable as the 

 radiometer for temperature measurement of exposed surfaces. 



