The aim of this study is to assess the performance of the mechanical ventilation system and air quality in an office building. The perfluorocarbon tracer (PFT) technique was used to measure air flow in an air handling unit and to estimate flow rates supplied to the office. In order to validate the PFT technique as a viable means of measuring air flow in the mechanical ventilation system, the PFT measurements were compared with measurements made using a pitot-static tube. Air exchange range, ventilation effectiveness and age of air were examined.

This paper critically examines the underlying premises of indoor climate control technologies and the HV AC industry (heating, ventilating, air-conditioning). It questions whether 'total environmental control' is possible, effective and desirable. The paper also reviews the methods and terminology of thermal comfort science focusing on the question of predictability of people's environmental preferences.

Personal exposure in a displacement ventilated room is examined. The stratified flow and the considerable concentration gradients necessitate an improvement of the widely used fully mixing compartmental approach. The exposure of a seated and a standing person in proportion to the stratification height is examined by means of fullscale measurements. A breathing thermal manikin is used to simulate a person. It is found that the flow in the boundary layer around a person is able to a great extent to entrain and transport air from below the breathing zone.

Mechanical ventilation of workrooms was formerly based mainly on the dilution principle. In recent years, however, 50% of new investments in industrial ventilation in Scandinavia have been spent on displacement ventilation. Very little data exist from industrial settings on the relative performance of displacement ventilation versus dilution ventilation as regards air quality and thermal comfort. The present study collected data on the indoor climate in a sewing plant before and after the ventilation was changed from dilution to displacement.