Electrostatic air cleaners (precipitators) were tested in four classrooms during ordinarylessons for four weeks. Airborne dust in the classrooms was collected on filters using two different kinds of samplers: IOM-sampler and a new kind of ionizing sampler. The amount of collected dust was evaluated by visual inspection (filter blackening) and the content of cat allergen was measured using an amplified ELISA assay. It was found that the filter blackening was 64% lower when the air cleaners were active than when they where inactive (p

Previous work on an Underfloor Air Distribution (UFAD) system with a single heat source anda single cooling diffuser at floor level developed by Lin has been extended to study the effects of the vertical location of the heat source and of multiple cooling diffusers. This is an attempt to produce more realistic models of UFAD systems. Both experimental and theoretical modeling is described in this paper. In the experiments, a plume and fountains represent a heat source and cooling diffusers respectively.

Tracer gas measurements are commonly used to estimate the fresh air exchange rate in a room or building. Published tracer decay methods account for fresh air supply, infiltration, and leaks in ductwork. However, the time delay associated with a ventilation system recirculating tracer back to the room also affects the decay rate. We present an analytical study of tracer gas decay in a well-mixed, mechanically-ventilated room with recirculation.

Amongst various sources of polluting substances the open space gas-range have an impact onthe quality of living spaces. Carbon-dioxide and nitrogen-oxides occurring during burning considerably impair the air quality. Emission of polluting substances has been examined in the Laboratory of Air Quality of Dept. of Building Service. The results of the research supported by the Ministry of Education (T0375 96) will be presented here.

The research was oriented to analyze better the ventilation systems, in terms of cost-to-quality ratio. The matter of the paper is that a ventilation system is designed to work in certain quality conditions, but every quality has its cost. This cost comprises investment, energy consumption and operation-maintenance expenditures.

The paper reviews the effect of environmental parameters on the migration of particulate matter. Themethodology involves simultaneous monitoring of particulate matter using dust monitor at indoor and outdoor locations along with the ambient environmental conditions. The study is of great significance as Particulate Matter (PM) has been reviewed in terms of particle count, which is more significant as compared to particle mass. In this paper, the variation of Indoor (PM) /Outdoor (PM) calculated on the basis of count are studied as a function of ambient wind speed, temperature and humidity.

A recent survey study suggested that elderly people’s lifestyle and building + dwellings factors exposed them to an uncomfortable and poor environment regarding indoor air quality. In order to confirm the qualitative statements of this study, measurements

A three-dimensional drift-flux model combined with the deposition boundary conditions for wall surfaces in ventilated rooms are presented to study the particle dispersion in displacement ventilation rooms. Three ventilating air flow rates, 2 ACH, 5 ACH, 8 ACH and several particle sizes, 1, 2.5, 5, 7.5, 10 micron, are investigated. The results show that the particle dispersion characteristics are very different in displacement ventilated rooms with different air supply volume. In rooms with the same air supply volume, large-diameter particles diffuse more widely than small ones.

Aerosol particles are one of the main causes to pollute indoor air. Reliable models for particletransport save time, money and help to reduce risk of health problems for occupants. In this work, we simulate particles transport in a two-zone enclosure with different particle characteristics. A statistically based analytical model is used for particles equilibrium whereas a Lagrangian model is employed to determine particle trajectories.

This paper reports experimental study of air quality in the kitchen of the CSTB experimental house MARIA. These experiments are transition between measurements in an experimental cell and in situ measurements. Indeed, ventilation conditions are controlled via either a hood or via a mechanical ventilation at the exhaust. The kitchen studied is also equipped with a pan on an electric cook-top which temperature is controlled. However, unlike measurements in test cells, wall temperatures cannot be controlled. Impact of cooking vapour on indoor air quality is analyzed using a tracer gas (SF6).