The assessment of the interaction of airborne contamination with building ventilation performance.

Investigations have been carried out over the last three years in industrial buildings having a variety of manufacturing processes. Data were collected on contaminant source and behaviour, exhaust ventilation, supply air, workroom pressure differentials, air currents in the workroom and discharges from exhaust ventilation systems. From these measurements a workroom air balance was drawn up and the re-entrainment of contamination from discharge into the breathing zone of people in the workroom was studied.