Characterisation of aerosol individual particles in a controlled underground area

The aim of this study is to determine the sources and provide a physico-chemical description of the airborne particulate present in two communicating underground areas: a highway tunnel with heavy vehicular traffic and a controlled underground laboratory. Individual particles were collected in the two zones and examined using scanning electron microscopy with EDS X-ray attachment. The principal components of the particulate were analysed using principal factor analysis and hierarchical cluster analysis. The data obtained suggest that three main factors determine airborne particulate pollution in the laboratory: the ventilation system for air replacement, the access of motor vehicles into the laboratory, and the metallic installations and structure of the laboratory itself.