Computational fluid dynamics has been used for assessing the thermal comfort and air quality in an office ventilated with a displacement system for a range of supply air conditions. Thermal comfort is predicted by incorporating Fanger's comfort equations in the airflow model. Indoor air quality is assessed according to the predicted contaminant concentration and local mean age of air. The performance of the displacement ventilation system is then evaluated based on the predicted thermal comfort and indoor air quality.

The present case study refers to a larger office building in Sweden. The employees in this building, which was built in 1982, began to complain about the indoor environment around 1985-86. A preliminary examination of the building started in 1989. The preliminary investigation showed that the concrete framed floors were levelled off with self levelling compound containing casein and that there were relatively high concentrations of ammonia under the PVC-flooring.

The acquisition of temperatures and velocities is a permanent recurrent task for the investigation of air flow in ventilated rooms. On the one hand it is important to measure the temperature and velocity field with a high spatial resolution. On the other hand, in general, varying outdoor conditions prevent from reaching a steady state and an additonal demand consists in short measuring times. Sometimes, the obtained measuring results are used both to supply appropriate boundary conditions for numerical computations and to verify the CFD-codes used.

The reason for the present project is the need for more reliable information about the actual ventilation conditions in naturally ventilated, detached houses. The aim has been to quantify the ventilation and humidity conditions and to establish a better basis for elaborating directions and guidelines on proper ventilation of detached houses. A national questionnaire survey covering more than 2100 households has been carried out, together with detailed investigations in about 150 houses.

The airflow between a warm room and cool exterior can be significantly affected by an external headwind. Pollutant concentrations within the space depend on the relative sizes of the wind and the undisturbed stack driven flow. Two scenarios are described. Firstly, a space is filled initially with buoyant polluted air. The space is then naturally ventilated through a single opening. In the "no wind" case, a gravity current of external air flows into the space. All the polluted air is expelled from the room.

In the frame of the European PASCOOL project, several experiments regarding single sided ventilation were carried out at BBRI in the outdoor PASSYS test cel. The test room of 30 m³ has a vertical window of about 1 m². During a first measurement period, an open cold box, which allows one to control the vertical wind speed, was placed in front of this window. During a second measurement period, the window was directly exposed to "real wind". The air change rates were evaluated by using two different methods: a tracer gas technique and the heat balance approach.

Four classrooms of two secondary schools located around Lyon in France have been monitored. The objectives are to analyse the quality of the indoor air and the thermal comfort and also the behaviour of the occupants towards opening of the windows. This paper briefly describes the context and the nature of the monitoring campaign, and presents the results of the measurements with direct interpretation of the ventilation needs.

New Zealand homes have traditionally been ventilated through open windows and by background infiltration. In recent times, new materials and construction practices have led to more airtight buildings, and open windows are seen more and more as a security risk. These trends call for new ventilation options that are inexpensive and consistent with home security, weathertightness and draught control. This paper is part one of a study of passive ventilation options for NZ homes.

A possible alternative to mechanical extract ventilation for kitchens and bathrooms is passive stack ventilation (PSV). BRE has carried out work on this type of system in a test house under controlled conditions. To find out how well they worked in practice, four occupied dwellings were monitored over a period of 2 - 3 weeks each. Each dwelling had two ventilation ducts. Air flow rates within the ventilation ducts were measured, together with humidities, temperatures and climatological data.

The Annex 27 (A27), Evaluation and Demonstration of Domestic Ventilation Systems, is given a genaral introduction. The habits varys a lot between individuals, the dwellings are of various sizes with various numbers of occupants being at home for longer or shorter times. Those facts needed to be collected in the beginning of the annex. In this paper background data will be given to make it possible to discuss the varied need for outdoor air supply in dwellings. Data for the parameters have been collected from many sources.