The development and construction of portable test equipment to determine air leakage has made it possible to carry out measurements on a large number of dwellings built using different construction technologies. The recording and analysis of the data collected is presented in this paper. This makes it possible to propose a method for taking sealing defects into account in the calculation of air infiltration of dwellings.

The filtering effects of three types of air control systems at two wastewater treatment plants on viable particles were investigated. Aspergillus fumigatus and other thermophilic organisms were used as monitors for viable particles. The indoor concentrations of viable particles were found to be affected by building design and the use of conventional mechanical air systems. Viable particles of approximately 4.0 microm and greater in aerodynamic diameter were filtered from the air while respirable size particles less than 4.0 micromwere not filtered as well.

This paper reviews the literature on sources and levels of pollutants in buildings and looks at the possible effects of a reduction in ventilation rates on the health and comfort of building occupants.

Large, multicelled and naturally ventilated buildings pose many inherent problems for the measurement of overall infiltration rates using tracer gases. Considering a single tracer gas decay technique, the most obvious problems are: (a) local variations in infiltration, (b) imperfect internal mixing of the air, and (c) practical difficulties in distributing (ie, seeding) the tracer gas and subsequently obtaining air samples.

Summarizes the factors affecting air infiltration, with definitions of the terminology used. Discusses minimum and optimum air change rate, and choice of ventilation system. Lists research in Switzerland.

Examines four pollutants found in significant amounts in biomass smoke: respirable particulates, carbon monoxide, formaldehyde and particulate benzo(a)pyrene, to effect a comparison between tobacco smoke and biomass fuel smoke. Nominal doses of formaldehyde and carbon monoxide are roughly similar. For respirable particulates, smokers receive more than a factor of 10 larger nominal doses. The reverse is true for benzo(a)pyrene.

A passive integrating radon gas dosemeter has been developed using electrochemically etched tracks in CR-39. The detectors were used in a survey of 2000 homes in the UK. The response of the dosemeters is shown to be linear with respect to exposure. It is shown that snap-on polyethylene lids allow 222Rn to diffuse into the detector cup while excluding radon daughters, dustand 220Rn. Initial results from a trial survey are presented.

Discusses indoor occupancy factors, including window opening habits, opening of internal doors, time spent indoors and patterns of occupancy, for inhabitants of the United Kingdom.

Discusses the future prospects of domestic ventilation and whether mechanical ventilation will be necessary to satisfy requirements as windows become more airtight. Suggests use of centralized mechanical ventilation, with openable windows for summer ventilation.

Reports on project designed to illustrate building and ventilation solutions which are or which can be expected to reduce the radon daughter content in indoor air in existing buildings or to prevent excessive radon daughter contents in newly-