Most people have at one time or another walked into a home or building and were faced with the unpleasant odors associated with sewer gas. Sewer gas is a complex mixture of toxic and nontoxic gases that can be present in a home, school, business, or other type of building depending on various circumstances.

Sewer gas is formed during the decay of household and industrial wastes. There can be highly toxic components of sewer gas which include hydrogen sulfide and ammonia. Sewer gas also contains methane, carbon dioxide, sulfur dioxide, and nitrous oxides. Chlorine bleaches, industrial solvents, and gasoline are frequently present in municipal and privately owned sewage treatment systems and these substances can also release gases.

“Having sewer gas indoors is not only a concern due to its offensive odors, there can also be health effects associated with exposure,” said Michael Berrevoets, President, VOETS, LLC. “In extreme circumstances there can be asphyxiation concerns and the potential for explosion hazards. Even low levels of sewer gas can lower property values and turn away tenants.”

Tips to help avert sewer gas issues indoors include flushing floor and sink drains and other plumbing fixtures with water to prevent the traps in the pipes to the sewer from drying out. Checking roof plumbing vents for any signs of blockage and ensuring that exhaust vents are not located too closely to air intakes or windows used for ventilation. Any cracks in vents and drain pipes could also allow sewer gas to enter a structure or if the plumbing was not built to code.

Finding the source of sewer gas can be a challenge, but the building science professionals at VOETS offer comprehensive inspection, testing, and monitoring services for sewer gases and other airborne contaminants. They have extensive experience in resolving these types of issues and access to the most advanced field instrumentation and testing services. VOETS also recently sponsored an educational video about sewer gas and exposure concerns that can be seen at: https://youtu.be/3mRydjd6uQQ