Online gas analysers, such as those within Protea’s range of emission monitoring systems, measure the stack or flue gas concentration from an industrial process continuously. Protea’s CEMs are either extractive, pulling a sample of the emissions gas into the analyser, or in-situ, where the gas is measured within the actual stack. A real-time concentration is given, usually every minute, and then our emissions monitoring software (DAHS) provides averaging and reporting of the gases.