LPG is Liquefied Petroleum Gas, a mixture of propane C3H8 and butane C4H10. It is a high-efficient and cost-effective energy source, commonly stored in cylinders for domestic use. When using LPG cylinders, safety precautions must be followed such as only using certified cylinders, not dropping or tampering with cylinders or safety valves, and keeping caps on when cylinders are not in use.