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In high voltage SF6 insulated switchgear, the level of SF6 concentration needs to be monitored regularly because of its degradation by switching arcs and on-going partial discharges or coronas. In the work reported here, measurements of SF6 dissociation rate following 75 μA positive and negative coronas have been made using a mass spectrometer and Raman spectroscopy. The two sets of data correlate well, the rates of degradation of SF6 and production of gaseous by-products being shown to be proportional to the charge transported by the corona. SF6 provides a particularly strong Raman signal at 773.5 cm-1, and the results demonstrate the feasibility of using Raman scattering to monitor SF6 degradation in high-voltage switchgear.