Sewer Gas

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What is sewer gas?

Sewer gas is a complex mixture of toxic and non-toxic gases that can be present at varying levels depending upon the source.  It is formed during the decay of household and industrial waste. Highly toxic components of sewer gas include hydrogen sulfide and ammonia.

Sewer gas also contains methane, carbon dioxide, sulfur dioxide, and nitrous oxides. In addition, chlorine bleaches, industrial solvents, and gasoline are frequently present in municipal and privately owned-sewage treatment systems.


Last Revised: December 1, 2014