MQ2 SENSOR is useful for gas leakage detecting(in home and industry). It can detect LPG, i-butane, methane, alcohol, Hydrogen, somke and so on. Based on its fast response time. measurements can be taken as soon as possible. Also the sensitivity can be adjusted by the potentiometer. 

MQ-2 Semiconductor Sensor for Combustible Gas:

• Sensitive material of MQ-2 gas sensor is SnO2, which with lower conductivity in clean air. When the target combustible gas exist, The sensors conductivity is more higher along with the gas concentration rising. Please use simple electrocircuit, Convert change of conductivity to correspond output signal of gas concentration.
• MQ-2 gas sensor has high sensitity to LPG, Propane and Hydrogen, also could be used to Methane and other combustible steam, it is with low cost and suitable for different application.