Optimal (Comfortable) Operative Temperature Estimation Based on Physiological Responses of the Human Organism

Abstract

Problems following the application of optimal operative temperatures estimated on the basis of PMV and the necessity to apply correct values in the new Czech Government Directive No. 523/2002 Code led to experiments based on the physiological human body response instead of solely people’s feelings in a given environment. On the basis of experiments on 32 subjects (university students) it has been possible to estimate: a) the total balance of hygrothermal flows between the human body and the environment, b) the optimal operative temperature as a function of the subject’s activity, c) the thermoregulatory range for each optimal operative temperature, i.e. maximal (category Cmax) limited by the onset of sweating, minimal (category Cmin) limited by the onset of shivering (category C can be applied to naturally ventilated buildings), optimal (comfort level – category A) defined by time constant 0.368 (can be applied to air conditioned buildings), and submaximum (decreased comfort level – category B) defined by time constant 0.632 (can be applied to buildings with basic air conditioning systems).