The Grove MQ9 Gas Sensor module is useful for gas leakage detecting (in home and industry). It can detect Carbon Monoxide, Coal Gas and Liquefied Gas.
The Grove - Gas Sensor module is useful for gas leakage detecting (in home and industry). It can detect LPG, I-Butane, Methane, Alcohol, Hydrogen, smoke and so on. Measurements can be taken as soon as possible based on its fast response time. Also the sensitivity can be adjusted by the potentiometer.
Each Grove - Gas Sensor Kit consists of one gas sensor base and four detectors, including MQ2, MQ3, MQ5 and MQ9. Below is a contrast table of them. You can switch the detector on the base according to specific target gases.