Toshniwal Sensing Devices offers Gas sensor manufactured by Figaro, Japan. They have high sensitivity to methane making it ideal for CNG leakage detection. The sensing element comprises of metal oxide semiconductor layer formed on an alumina substrate of a sensing chip together with an integrated heater. In the presence of CNG the sensor"s conductivity increases depending upon the gas concentration in air. A simple electrical circuit can convert the change in conductivity to an output signal, which corresponds to the gas concentration. Due to its low sensitivity to alcohol vapours (typical interference gas in domestic/automobile environment), the sensor is ideal for domestic/automobile gas alarms. Due to miniaturisation of the sensing chip, TGS-2611 requires a heater current of only 62 mA and the device is housed in a standard To-5 package. Gas sensors for other gases such as CO2, O2, CO, alcohol, LPG and LNG, H2, H2S, etc, are also available.