Conditions of ensuring thermal comfort for human beings

The conditions under which the man can achieve the state of thermal comfort are taking into consideration the temperature of the air of a certain space, the humidity of the air, the speed in which the air (currents) are moving and the average radiating temperature (the temperature of the interior surfaces of the elements closing a space). Estimating the thermal comfort is done through two different parameters: PMV (Predicted Medium Vote), which represents the average opinion of a group of people questioned regarding the thermal sensation of a space (measured with values within -3 and +3); and PPD (Predicted Percent of Dissatisfied), which represents the percent of dissatisfied people that were exposed to the same spatial ambiance. The parameters in which the PMV is measured are: the metabolic activity, the clothing, the temperature of the air, the average radiating temperature, the humidity and the speed of the movement of the air. The performance levels of a certain space ought to be a PPD<=10%.