The transcutaneous partial pressures of oxygen (tcpO2) and carbon dioxide (tcpCO2) were measured at eight different sites in 10 adult male subjects with an electrode at a temperature of 44 degrees C. The mean tcpO2 values (mmHg) were significantly lower on the face (forehead 26.6, cheek 29.6) and the palm (26.4) than at other sites (60.6-69.6). The tcpCO2 values (mmHg) were only slightly higher on the face. Removal of the stratum corneum produced an average increase of the tcpO2 on the palm of 37.6 mmHg and on the forehead of 19.6 mmHg. However, in 10 children with an age range of 3-9 years, the difference in the mean pO2 between the cheek and forearm was very small. There was no significant difference in the cutaneous blood flow at 44 degrees C between the cheek, palm and forearm.