Photoacoustic Extinctiometer (PAX): This is a sensitive, high-resolution, fast-response instrument for measuring optical aerosol properties relevant for climate radiative forcing and carbon particle sensing. The instrument directly measures in-situ light absorption and scattering of aerosol particles, from which it derives extinction, single scattering albedo and black carbon (soot) mass concentration. read more =>

Single Particle Soot Photometer (SP2): This is an ideal instrument for black carbon measurement. The SP2 is the only probe in the world that directly measures the black carbon, known as soot, in individual aerosol particles. The high sensitivity, fast response, and specificity to elemental carbon makes it the premier instrument for characterizing pollution sources, black carbon in snow, ice or water, calibrating aethalometers and documenting thin, atmospheric layers of contamination. read more =>

Photo-Acoustic Soot Spectrometer, Three Wavelength (PASS-3): The PASS-3 is a sensitive, high-resolution, fast-response instrument for measuring the absorption coefficient of aerosol particles. It uses three wavelengths (red, green, and blue) to enhance measurement capabilities.read more =>

Photo-Acoustic Soot Spectrometer, Single-Wavelength (PASS-1): The PASS-1 is a sensitive, high-resolution, fast-response instrument for measuring the absorption coefficient of aerosol particles. This instrument has no filters to change and requires no intervention by the operator. The PASS is ideal for air quality and biomass burning studies, as well as for documenting pollution plumes from power plants, urban areas or other sources of black carbon emissions such as diesel exhaust emissions. read more =>