Air quality work at Guelph: GAViM and a traffic tunnel study

The Guelph Aerosol and Visibility Monitoring (GAViM) program presently runs three monitoring sites: two rural sites compatible with the IMPROVE protoc ol and one urban site mostly for special comparison studies. Fine aerosol i s analyzed by the Laser Integrated Plate Method (LIPM), Proton Elastic Scat tering Analysis (PESA), Proton Induced Xray Emission (PIXE) and gravimetric analysis. Air quality data from the presently running sites and from two r ural sites operated in the past are available through the WWW. The Guelph S canning Proton Microprobe Laboratory also participates in other aerosol pro grams: PIXE was employed to determine the composition of the ambient aeroso l in a Vancouver traffic tunnel, to identify the main emission sources and to make estimates of vehicle emission factors, The PIXE facility was also m odified for analysis of size-fractionated samples from the PIXE Internation al Cascade Impactor (PCI) sampler, Significant improvement in detection lim its for light elements due to the two-detector PIXE system used in Guelph, was justified particularly because of low air particulate loadings in case of PCI, (C) 1999 Elsevier Science B.V,All rights reserved.