Abstract
A tracer gas (helium) has been used to determine the emission rate of a gaseous pollutant source of acetone. The method principle consists of measuring the pollutant concentration in the vicinity of the source and the pollutant transfer coefficient determined with the tracer gas. The ratio of the pollutant concentration by the tracer gas transfer coefficient gives the pollutant emission rate. The study demonstrates the validity of the tracer gas method for determining the emission rate of a pollutant source comprising a solvent bath. Nevertheless, limitations were highlighted when the source was placed in very still air (air velocity above the bath less than 10 cm/sec approximately). For that particular ventilation condition it was difficult to have a tracer emission representative of that of the pollutant source due to the high fluctuations of the pollutant emission rate. On the other hand, the helium and acetone transfer coefficients have been found equals whatever the ventilation in the vicinity of the solvent bath, when the tracer emission gives a true representation of the pollutant source. This method is intended to be used for on-site measurements of gaseous pollutant emission rates such as solvents or acids emitted from surface treatment tanks.