Gas – LPG Gas sensor – MQ-6

This is a simple-to-use liquefied petroleum gas (LPG) sensor, suitable for sensing  LPG (composed of mostly propane and butane) concentrations in the air. The MQ-6 can detect gas concentrations anywhere from 200 to 10000ppm.

Sensor at Sparkfun

Datasheet

Wiring example (can be used similarly with Arduino)