English

To elucidate any connection between high radon concentrations and low-infiltration houses, the 222Rn concentrations and infiltration rates have been measured concurrently in US houses. Three housing surveys have been undertaken: one in energy-efficient houses located throughout the US and twoin conventional houses in the San Francisco area and in Maryland. In each of the groups surveyed, no clear correlation was observed between 222Rn concentrations and infiltration rate, although each parameter varied over a wide range.

Increased air tightness in new energy-efficient housing has led to serious problems with excessive indoor moisture in winter as well as with other trapped indoor air contaminants. Heat recovery ventilation systems are being used increasingly

Addresses air leakage of warehouses and light industrial buildings including the significance of infiltration/exfiltration, air leakage sites, and measurement techniques. Concludes that 1, only limited leakage data are available for components of this building category 2, no model has been developed specifically for use in warehousing and light industrial buildings. However, one of the existing models for residential buildings could possibly be adapted.

Describes the first stage of a project to study domestic background leakage. Fundamental flow measurements have verified the crack flow equation for the simplest crack type for a much larger range of crack and flow parameters than have previously been examined. It is hoped to develop a portable, automated pressurization system capable of identifying and quantifying background leakage areas in rooms.

The ventilation of a large room is often achieved by supplying inlet air from a small side-wall mounted opening. The velocity distribution in a typical room with a small circular inlet opening close to the ceiling is described. The supplied air forms a wall jet below the ceiling which is easy to describe in terms of velocity distribution, entrainment, etc. The jet is deflected at the end wall opposite the supply opening and the resultant flow in the lower part of the room - the occupied zone - has a rather complicated structure.

As airtight houses become more popular across Canada, reduced ventilation rates may lead to poor air quality and high humidity problems in these dwellings. This paper reviews the needs for ventilation, ventilation methods and systems, and current codes and standards, particularly with respect to airtight and energy efficient houses. Current research in Canada is reviewed and considerations for a new ventilation standard are discussed.

The state of practice in Canada, as described in the literature, concerning ventilation, air distribution and air quality in warehouses and light industrial buildings is reviewed. There is little documented field information available. Modelling processes have not been developed which can provide thenecessary detail. Measurement of air flows, both in the field and in models, is difficult. The regulatory environment in Canada allows considerable innovation in developing conservation procedures.

Describes a five month study which measured radon concentration, air exchange (ventilation) rate, weather and radon source parameters in a house near Chicago. Factors influencing radon entry rate were investigated. Discusses the measurements presented, noting some patterns in the data which are hard to explain. Applies two models for radon entry rate to high and low airborne alpha activity at the sump.

The design and calibration of a passive sampler operating according to the diffusion principle and its application to the analysis of indoor air are described. Taking aliphatic and aromatic hydrocarbons as representative pollutants, it is demonstrated that at constant concentration, the amount of substance trapped by the sampler is a linear function of the time of exposure. An equation is given relating this amount of substance to the mean pollutant concentration. The detection limit is of an order of 300 microgram/(m3.h).

This document reports on analytical work carried out in cooperation among three European laboratories. The purpose of this work was to carry out a first assessment on the performances of passive samplers for organic vapours when used in indoor air pollution monitoring and simultaneously to evaluate theinterlaboratory agreement on low concentration analysis of a variety of volatile organic compounds. Two types of passive samplers were thus exposed in the different facilities and replicate specimens were analysed at each of the three laboratories.