The Magee Scientific Aethalometer® measurement principle is based upon the absorption of light by the aerosol sample, while continuously collecting on a filter. The filter tape advances automatically when a pre-set loading limit is reached, permitting the instrument to operate without attention. Depending on aerosol concentration levels, each roll of filter tape will last from one to several months of operation.

Sample collection and analysis is performed on two filter spots simultaneously at different flow rates. Mathematical combination of the data eliminates the “Filter Loading Effect” and provides continuously-compensated data in real time with no discontinuities at filter advances. The parameters derived from this analysis also offer additional insights into aerosol composition and aging.

Analysis is performed at seven optical wavelengths from the UV (370 nm) to the IR (950 nm). The spectral behavior of optical absorption by diesel exhaust emissions is completely different from that of smoke from biomass burning. Analysis of the spectral patterns from the 7-wavelength data allows for a real-time separation of ‘traffic’ and ‘biomass’ emissions. This allows for a speciation of the aerosol sources and a determination of their origins.

Light-weight design with external 12 V power supply (available optionally) for portability is offering operation up to 15 hours. Additionally, we offer a lightweight waterproof, crushproof and dustproof transit case for field transportation.