The following report documents the design and development of an automatic vent closure system for residential exhaust systems. The report discusses the rationale behind the perceived need for such a system and defines the objectives of the design and development work with respect to these needs. A detailed account of the development of the design and construction of successive prototypes will be given along with a thorough description of the testing procedures employed to evaluate the operational characteristics of each prototype as their design was further refined and developed.

The Air Lock Floor and the Pressure Ring are two effective measures for control of air flow directions between rooms or zones in buildings. They create a pressure hierarchy that controls spread of pollutants. Here an example has been given for radon from a crawl space, odours from a bakery into a dwelling above and an isolation chamber with a leaky facade. The Air Lock floor can operate with a 7 W fan and at the same time extractthe normal dwelling ventilation flowrate. Used in the ground floor, the Air Lock Floor results in a warmer floor and contributes to energy savings.

The purpose of this study was to test an Indoor Air Quality model on a variety of Canadian homes, and use this model to determine the optimal ventilation levels necessary to provide appropriate comfort levels. The Indoor Air Quality model tested (the AQ1 program), was a single zone hour-by-hour model of air leakage, mechanical ventilation and pollutant concentration. Measured weekly air change rates were compared to the model's predicted rates, and sensitivity analysis' performed on a number of inputs.

This paper investigates possible natural ventilation strategies to reduce exposure to environmental tobacco smoke (ETS) in dwellings. Particular attention is paid to the migration of tobacco smoke from the living room (usually the smoking room) to the bedrooms which may be occupied by children. This addresses an area of current concern regarding the possible association between passive smoking and adverse health conditions; in particular the link between parental smoking and respiratory illness in children.

Occupant response in a good indicator of the effectiveness of a ventilation system. In a one-year study in the province of Quebec region, 20 public buildings were studied. Occupants were asked to answer questions on their perception of their environment and the ventilation at their workstation. Annual energy consumption for each building was recorded. The ventilation systems were studied as well as their rates; minimum outdoor air rates and average total air rates, at each workstation and at the ventilation system. Ventilation rates were plotted against energy consumption.