Sensors for measuring combustibles in the absence of oxygen

Calorimetric and semiconductor types of sensors for combustibles generally require the presence of oxygen in the measurement gas. This paper describes sensors incorporating at least one ZrO2 electrochemical cell together with a combustibles-sensing element that are capable of measuring combustibles even in the absence of oxygen. The ZrO2 cell is used as an oxygen pump to introduce into the sensor structure the amount of oxygen necessary for the proper operation of the sensing element. Devices of this type can also be used to determine the composition of simple fuel mixtures. Results of experimental investigation of these devices concepts are presented.