Document 5kBmJwR7rX9N6R1EZj59aBQMR
Heating Ventilating Air Conditioning Guide 1939
OPTIMUM AIR CONDITIONS
No single comfort standard can be laid down which would meet every need. There is an inherent individual variation in the sensation of warmth or comfort felt by persons when exposed to an identical atmos pheric condition. The state of health, age, sex, clothing, activity, and
Chapter 3. Physical & Physiological Principles of Air Conditioning
heat regulating mechanism of the body. This belief is strengthened by results of studies on premature infants over a four-year period24. By adjusting the temperature and humidity so as to stabilize the body tem perature of these infants, the incidence of diarrhoea and mortality was decreased, gains in body weight increased and infections were reduced to a minimum.
Winter Comfort Zone and Comfort Line
In Fig. 6 is shown the A.S.H.V.E. winter comfort zone which was determined experimentally with large groups of men and women subjects wearing customary indoor winter clothing. The extreme comfort zone includes conditions between 60 and 74 deg ET in which one or more of the experimental subjects were comfortable. The average comfort zone
the degree of acquired adaptation seem to be the important factors affecting the comfort standards.
Since the prolonged effects of temperature, humidity and air move ment on health are not known to the same extent as their effects on com fort, the optimum conditions for health may not be identical with those for comfort. On general physiologic grounds, however, the two do not differ greatly since this is in accordance with the efficient operation of the
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Fig. 5.- Cooling Effect of Three Cold Walls in a Small Experimental Room, as Determined by Comparison with Sensations in a Room of Uniform Wall and Air Temperature
includes conditions' between 63;and 71 <lGg.-;ET conducive to comfort in
50 per cent or more of the experimental subjects. - The most popular
effective temperature was found to b.e 66 deg, and was adopted by the
Society26 as the winter comfort line foc indiyiduajs at rest wearing custom
ary winter clothing.
...
The comfort line separates the cool;,a.tr conditions to its left from the warmair conditions to its right. Under the air conditions existing along or denned by the comfort line, the body is able to maintain thermal
and<KBOD<:aB^tf^if/PSnuiS0Sinito Premature Nurseries in Hospitals, by C. P. Yaslou. Philip Drinker U' B ckfan (A.S.H.V.E. Transactions, Vol. 36. 1930, p. 383).
Vol. 38^932 p^iO)' EfIeCtive T'u'Perature index and Comfort Charts (A.S.H.V.E. Transactions,
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