pollutant

The ventilation efficiency in a displacement ventilated room with non-buoyant pollutant sources was evaluated under laboratory conditions. The contaminant removal effectiveness was measured for different positions of the pollutant sources and with different ventilation flow rates. The air change efficiency and the temperature gradient in the room was measured for the different ventilation flow rates. The contaminant removal effectiveness was much dependent on the position of the sources and varied from 30 to 240 %.

The New Zealand Building Code has kept with tradition in allowing residential building ventilationdesigns based entirely on openable window areas. Working against this tradition, however, is a trend inNew Zealand towards more airtight construction and declining reliance on open windows. Contributingto this trend are changing patterns of occupancy with fewer people at home during the working week,along with developing concerns for personal security.

The purpose of this report is to summarise the work of IEA Annex 18 on demand controlled ventilation. It is primarily aimed at building services practitioners, designers and policy makers who require background knowledge of the operational principles and range of applicability of this approach to ventilation. The primary focus is on applications and the conditions required for the operation of such systems. This international activity has been carried out by a working group of researchers from ten countries (Appendix 1) with Sweden bearing the main responsibility as Operating Agent.