pollutant

In order to study pollution dispersion in built up area, aeraulic simulation at reduced scale in a boundary layer wind tunnel is intensively used at CSTB. The experimental set up and the associated procedures are described here. A comparison with complementary approaches developed at CSTB, numerical simulation and full scale measurements using tracer gas release is also provided.

This paper identifies the significance of pollution at five sites amongst the worst on the British mainland hence indicative of other polluted areas within Europe. Three sites are located in London and one each in Birmingham and Cardiff. The pollutants examined are NO2, SO2, O3 and PM10. Newly proposed DOE figures defining poor air quality have been used to re-examine the frequency of excess pollution episodes between 1992-1995. The results identify the most appropriate periods for natural ventilation of offices in urban areas in terms of the hour in a day and time of year.

Laboratory hoods are designed to capture contaminants generated in the laboratory and discharge them outside. In many laboratories this results in several fan systems. To provide a convenient location for maintenance to service the fans, the fans are often located in penthouses. Good design of laboratory ventilation requires that the duct be negative in occupied spaces. However. it is not possible to design a fan room or penthouse with the duct negative downstream of the fan.

This paper presents results of applying the capture and containment test procedures in ASTM Fl 704-96, Standard Test Method for Performance of Commercial Kitchen Ventilation Systems, to determine the threshold capture and containment exhaust flow rates for a number of cooking appliances and two types of kitchen exhaust hoods.

The influence of wind is an important part of the bioclimatic town planning criteria. Ventilating and mechanical action of the wind towards reduction of air pollution in urban areas is becoming increasingly important and must be analyzed along with other factors such as · thermal losses, comfort etc.

Air quality in urban areas is often poor, creating problems for local buildings forced to ventilate with polluted air. Most of the pollution comes from traffic, with the worst periods during rush hours. What role can the automatic control of ventilation play in reducing the impact of pollutants?