Abstract: The monitoring of oxygen percentage in flue gases is one of various ways of controlling efficiency
and emissions of industrial combustion. In general, flue gases analyzers are expensive and not accessible to
small scale industries. The automotive Lambda sensor is an oxygen sensor which controls the electronic
injection of the modern internal combustion vehicles. The aim of this study is to present two methods of
measuring the oxygen concentration in flue gases of industrial combustion by the use of the automotive
Lambda sensor. One method uses the voltage signals of a heated Lambda sensor and the other one uses the
Current Reversal Mode (CRM) of operation of such sensor. Results presented in this study show that such
methods are effective to control industrial combustion.