The BC 1054 Multi-spectrum Black Carbon Analyzer from Met One Instruments Powered by Acoem continuously measures the transmittance of light across filter media onto which particulate matter is accumulating and in real-time calculates the black-carbon “BC” concentrations at 10 different wavelengths ranging from the near-UV to the near-IR. By employing the same widely accepted calibration constants and principles of operation as those used in the Magee Aethalometer, the BC-1054 produces nearly identical results, but at a fraction of the cost.