Adjustment to the climatic conditions in the Sinai desert (Hebrew)

To determine the influence of the Sinai desert climate on ability to lead a normal life and work efficiently, 18 acclimatized workers in the Abu Rodes oil field, aged 22 to 24 yr, were examined. 13 were examined at the beginning of July when the ambient temperature averaged 25° to 38°C (D.I. less than 28 units) and seven were examined at the end of July, a month in which the ambient tempeature averaged 30 to 40°C (D.I. over 28 units during most working hours, the danger limit for a hardworking man). The subjects worked 12 hours a day, including short breaks. Living quarters were not air conditioned; the water supplied was cool, but did not remain so for very long, The work was moderate to hard. The average fluid intake was 4.0 L/12 hr on each of the examination days. Body temperature and pulse rate were within normal limits during the first examination day, as were serum electrolytes and osmolarity. However, body tempeature and pulse rate rose to high values during the second of the examination days, on which two of the workers became so dehydrated that they required intravenous fluids. The findings indicate that although the workers were in good physical condition and were well acclimatized, they were in poorer condition on the second examination day, when heat stress was the greatest. It is concluded that even acclimatized workers need to be encouraged to drink in order to replace fluid lost through sweating. Cold drinks (10 to 13°C) should be made available in quantity at all times. In addition to proper drinking habits, breaks from physical activity in air conditioned buildings must be taken in order to maintain work efficiency in the Sinai desert climate.