1. Field Methods of Monitoring Atmospheric Systems Measuring the Size Distribution of Particulate Matter Copyright © 2006 by DBS

2. Introduction Diameter (μm) Commonly used term < 0.1fume 0.1-10smoke 10-100dust > 100grit

3. Sources e.g NH 4 Cl, SO 4 2- / NO 3 - salts Natural: forest fires, volcanoes etc. Man-made: fossil-fuel combustion, industry Mineral dust from weathering of rocks and soils Chemical composition can be used to ID source and fate

4. Particle Size Distribution Source: Keywood, M Fly ash Coal dust Sand

5. Particle Size Distribution Classify via Aerodynamic diameter (> 1.0 μm) –Use multistage impactor Electrical mobility (0.01-20 μm) –Electrical field strength is increased to remove progressively larger particles –Aerodynamic Particle Sizer Light-scattering properties –Intensity of scattered light is proportional to particle size Boubel et al, 1994 http://www.tsi.com

6. Further Reading Journal articles

7. Text Books Hesketh, H.D. (1994) Air and Waste Management: A Laboratory/Field Handbook. CRC Press, Florida. Lodge, J.P.A. ed. (1988) Methods of Air Sampling and Analysis, 3rd Edition. CRC Press, Florida. Wight, G.D. (1994) Fundamentals of Air Sampling. CRC Press, Florida. Winegar, E.D. and Keith, L.A. eds. (1993) Sampling and Analysis of Airborne Pollutants. CRC Press, Florida.