| Abstrakt: |
The N.S.W. Division of Occupational Health was requested to provide information to assist a Mines Rescue Station to choose a type of self-contained breathing apparatus which would be likely to permit the greatest duration of exposure of Mines Rescue personnel to hot and humid environment whilst performing heavy work, without collapse. A number of subjects were tested in a heat chamber, performing a work cycle of 2 minutes duration, followed by a 3-minute rest period, at temperatures of 30°c, 35°c, 38°C and 4l°c Dry Bulb with a Wet Bulb temperature about 1° lower in each case, until the subject was either unable to continue or until the rectal temperature reached 38·8°c to 38·9°c. Pulse rates, skin temperature, and sweat losses were also recorded. The experiments confirmed that a rectal temperature of 38·8°c to 38·9° will, in most cases, coincide closely with the onset of exhaustion. Sweat loss and pulse rate were found to be unreliable methods of measuring fatigue and that skin temperature was completely unreliable as an index of fatigue except when the temperature and humidity were high. [ABSTRACT FROM PUBLISHER] |
