Sewer gas in your home causes not only an unpleasant smell, but it can create a threat to your safety. Sewer gas has a distinctive rotten eggs smell that comes from the mixture of toxic and nontoxic gasses rising from a drain pipe. In high concentrations, these gasses can cause serious symptoms like nausea, dizziness, unconsciousness or death. For homeowners, the risk of a methane-gas explosion increases with very high concentrations of sewer gas, if ignition of the gas occurs. Fortunately, finding the source of the gas often leads to an easy solution to the smell.
Locate the point of entry for the sewer gas. The most likely culprit of sewer gas smell results from water trapped under a floor drain, laundry sink or wash basin. Water can evaporate from these drains after infrequent use, allowing the sewer gas to penetrate the house.
Pry open your floor drain using the standard screwdriver. While wearing the waterproof gloves, check the drain for a cleanout plug. The drain will have two pipes leading downward, and the cleanout plug functions as a stopper for the shallower pipe.
Seal the shallower pipe with a cleanout plug replacement that you can purchase at any local hardware store.
Check the drain for dryness by peering into the drain. You should see a small pool of water filling the elbow of the pipe.
Pour a pitcher of water into the drain if you have a dry drain or if you haven't used that drain for more than a month.
Pour three to four tablespoons of cooking oil into the drain on top of the water. The oil will create a seal, preventing sewer gas from reentering the home as the water evaporates.
Flush any toilets that you have not used in the last month. Toilets can leak sewer gas if the water in the toilet trap has evaporated. Flushing the unit will replenish the water in the trap.