Application of industrial painting is often carried out by air-atomization. In this case, health hazards arise from the exposure to solid and liquid aerosols as well as to solvent vapors. Control of these airborne pollutants may be achieved through the use of a spray booth, whose effectiveness depends also on the number and dimension of the openings, on the main air flow rate, as well as on the direction and flow rate of secondary air streams.

There has been lack of fact-based knowledge for design and operation of supply-air filters for general industrial ventilation. A multi-company project within the Industrial Ventilation (INVENT) technology programme was started in 1994 to tackle this problem area which is assumed to be the most problematic one, according to the feedback from end-users in several industries, who also made the initiative to this project.

Local exhaust ventilation systems are normally the most cost efficient method for controlling air pollutants and excessive heat. For many manual operations, capturing pollutants at or near their source is the only way to insure compliance with threshold limit values in the workers breathing zone. Local exhaust ventilation optimize ventilation airflow thus optimizing system costs especially where recirculation is not used.

This paper discusses two complementary techniques for modeling human exposures to airborne contaminants with a focus on control decisions involving ventilation. Particular attention is given to: (I) the use of empirical-conceptual models with dimensional analysis and (2) computational fluid dynamic simulations. Both techniques provide valuable information. An empirical -conceptual model is formulated with dimensional analysis for a spray painting operation.