Narrow Results

It is demonstrated in this work, that PIXE is a good mass indicator for suspended particles in urban environments. Results are presented for several samplings performed in urban and other environments in Chile and other countries. Aerosols were collected on filters operated by a Stacked Filter Unit (SFU) in the range of particles < 15 µm (PM₁₅) and < 10 µm (PM₁₀), mainly the respirable fraction. For samplings performed in downtown Santiago, the sum of the concentrations of the elements detected by PIXE correlated well with the indices of respirable suspended particles (RSP) measured by gravimetry. There was no high correlation for other samplings, near a crushing plant and near mineral storage. On the average, the sum of the PIXE results for Santiago’s aerosols represents about the 15% of the total mass collected in the respirable fraction. A measurement of collection efficiency for the 0.4 µm Nuclepore filter was performed by means of PIXE and gravimetry. These results were η_PIXE=0.98 and η_balance=0.96, for the PIXE and the gravimetric method.