What To Do If You Smell Sewer Gas In Your Home

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Do you smell rotten eggs or sewer gas in your home? It's a sign of a plumbing problem.
It’s not healthy to breathe sewer gas. In fact, sewer gas can be dangerous.
The foul smell is hydrogen sulfide, a gas that comes from decaying organic matter, aka sewage.
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In a residential home, it exists in low levels and can occur if a plumbing problem exists. When the home’s plumbing system is working properly, the naturally-occurring hydrogen sulfide is directed up and out of the building through a vent system, which exits through the roof. No smell should be present.
That's why you should learn how to tell if your home might have a leak and get it fixed immediately.
Basement floor drain a common source of sewer gas
When we smell this gas in homes, many times it's caused by a small problem, such as a dried out water seal in a floor drain. Other times a sewer gas smell is a sign of a bigger problem, such as a broken sewer or vent stack. Diagnosing this problem can be simple or complicated, depending on the cause of the problem.
Hydrogen sulfide is dangerous even at low levels. Prolonged exposure to sewer gas can cause irritability, headaches, fatigue, sinus infections, bronchitis, pneumonia, loss of appetite, poor memory and dizziness. It affects people and pets that are exposed to it over a long period of time. Even if the smell comes and goes, it needs to be addressed. Likely there is a blocked, broken, cracked or deteriorated pipe allowing the gas to enter your home. It’s not going to go away until it's repaired.

Dried out water seal in a floor drain can also be the source of sewer gas smells in your home. (Photo by Steve C. Mitchell)
Where is hydrogen sulfide gas smell strongest?
Hydrogen sulfide is a heavy gas and is strongest near the floor or ground. Once exposed to the smell you will become desensitized to it, which causes you to think it is no longer present. Hydrogen sulfide never occurs in high levels within homes because of the small amount of sewage and the amount of fresh air that moves through the system.
In large municipal sewers and in industrial settings, this gas can be found at much higher levels and cause sudden death. The Occupational Health & Safety Administration (OSHA) has put strict regulations in place at industrial settings where proper equipment to measure the levels and respirators are used.
If you smell rotten eggs in your home, you don't need to evacuate the building. However, you should call a plumber as soon as possible.
About this Experts Contributor: The Scottish Plumber is the trusted drain and sewer professional for Chicago and its suburbs with fast, reliable service from its friendly technicians.
As of June 17, 2015, this service provider was highly rated on Angie’s List. Ratings are subject to change based on consumer feedback, so check AngiesList.com for the most up-to-date reviews. The views expressed by this author do not necessarily reflect those of Angie’s List.