Sewer gas Sewer gas Sewer gas is a complex mixture of toxic and nontoxic gases produced and collected in sewage systems by the decomposition of organic household or industrial wastes, typical components of sewage. Sewer gases may include hydrogen sulfide, ammonia, methane, esters, carbon monoxide, sulfur dioxide and nitrogen oxides. Improper disposal of petroleum products such as gasoline and mineral spirits contribute to sewer gas hazards. Sewer gases are of concern due to their odor, health effects, and potential for creating fire or explosions. Sewer gas is typically restricted from entering buildings through plumbing traps that create a water seal at potential
2014 Kaohsiung gas explosions sky and flames reaching 15 stories high. The blasts ripped up roads, trapped and overturned cars and firetrucks, and caused a blackout to the electrical grid. About 6 km of road length were damaged. The explosions reportedly blew cars and motorcycles high up in the air; some vehicles and victims were found at the rooftops of buildings three or four stories high. One street had been split along its length, swallowing fire trucks and other vehicles. Premier Jiang Yi-huah stated that there had been at least five blasts around the city. The blasts cut gas supplies to 23,600 households, electricity