Document dYXLrLrg5pqNZ6LLa8Y3mevxb

American Society of Heating and Ventilating Engineers Guide, 1936 Definition of Effective Temperature Briefly, effective temperature may be defined as an arbitrary index of the degree of warmth or cold felt by the human body in response to tempera ture, humidity, and movement of the air. Effective temperature is not a true temperature of the air but an index which combines temperature, humidity and air motion in a single value. The numerical value of the -Ventilation and Air Conditioning Standards Chapter 3- signifies the minimum air movement it was possible to obtain in the Laboratory's psychrometric chamber. Actually, the air motion was between 15 and 25 fpm in all experiments, without qualification, as measured by the Kata thermometer. This was not a linear movement of air but it represented the turbulence or eddy currents produced by the air effective temperature index for any given air condition is fixed by the temperature of saturated air which, at a velocity or turbulence of 15 to 25 fpm, induces a sensation of warmth or cold like that of the given condition. Thus, any air condition has an effective temperature, of 65 deg when it induces a sensation of warmth like that experienced in practically still air at 65 F saturated with moisture. In all reports of the A.S.H.V.E. Research Laboratory, the term still air 64 uiv ma jo aNnod tad 3am.ston jo smvho change. Even in tightly sealed rooms, the natural air movement is not likely to fall below 10 fpm so long as there is a temperature or pressure difference between the air inside and that outside the room. The relation of temperature and humidity to comfort for persons normally clothed and at rest in still air is given in Fig. 1, while the effect of various air motions upon comfort for persons normally clothed at rest for velocities of 100 and 300 fpm are given in Figs. 2 and 3. The difference