Gas mainly contains natural gas, liquefied petroleum gas, gas. Natural gas is mainly composed of methane, propane, ethane, and a small amount of nitrogen and carbon dioxide. Natural gas in the production and transportation process, the potential gas leakage risk, and natural gas is flammable, high temperature and open fire prone to explosion and fire. The project uses the ASD5330, ASD5300 gas detector and JB-TB-ASD5120 alarm controller to protect the gas industry.