Ultraviolet photometry analyzer has 2 measuring ranges as ppm or Vol.-%, and can also realize high-precision up to ppb range. It can measure 2 gas components simultaneously by using 2 UV-LEDs. Nitrogen oxides (NO+NO2), hydrogen sulphide(H2S), ozone(O3), sulphur dioxide(SO2) and chlorine(Cl2) can be measured.
Please see details in Ultraviolet photometry Analyzer.