Aethalometer® AE33

The Aethalometer® AE33 incorporates the patented DualSpot™ measurement method.  This completely solves the loading-dependent nonlinearity, which affects the data from any filter-based optical analyzer.  The method explicitly does not require any knowledge or assumption about the existence, origin, or magnitude of any optical nonlinearity. In fact, the calculation yields the “Loading Compensation Parameter” as an instrumental data output, which may offer insights into the origins and optical properties of the aerosol.

The analysis is performed at 7 optical wavelengths spanning from the near-infrared (950 nm) to the near-ultraviolet (370 nm).   The sequencing of illumination and analysis is performed on a 1-Hz timebase.  This yields the complete spectrum of aerosol optical absorption with one data line every second.

An Aethalometer model (Sandradevi et.al. from 2007) is used in real-time to calculate the fraction of BC that may be attributed to biomass combustion.

The optical performance of the Aethalometer® AE33 may be validated by the ‘Neutral Density Optical Filter Kit,’ consisting of four precision optical elements whose absorbance is traceable to fundamental standards.  Software routines measure the optical intensities at all wavelengths and compare the analysis instantly with the original reference values.  Other built-in test programs offer routine checks of stability and leakage.  These features provide Quality Assurance that is essential both for routine monitoring and research use.

User and communications interfaces permit remote monitoring of operation; data retrieval; performance of internal tests; and reporting of state-of-health parameters.