Design and implementation of a mini passive DOAS system for retrieval SO2 gas columns

The Differential Opitcal Absorption Spectroscopy (DOAS) is a technique to measure pollutant emissions like SO2, NO2 from point sources and total fluxes in the atmosphere. Passive DOAS systems use the solar radiation as the light source. Measurements with such systems can be made in situ and in real time. The goal of this work is to report the design and implementation of hardware and software of a portable system to evaluate the pollutants emitted in the atmosphere by industrial chimneys. We show SO2 measurements obtained around PEMEX refinery in Tula Hidalgo than enables the identification of their pollution degree.