The MQ-8 gas sensor is highly sensitive hydrogen and less sensitive to alcohol, and cooking fume. It could be used in gas leakage detection appliance in family and industry. The resistance of the sensor component changes as the concentration of the target gas changes.
There are two modifications of the sensor:
Standard - with sensitivity.
With analog and digital outputs - with the amplifier output signal and adjusting the heating element sensor. You can configure the sensor to a certain threshold, and connect to the digital input of the microcontroller.