A: The purpose of a trap is to hold water to prevent sewer gas from entering a room. 99 percent of the time, sewer gas smells occur due to a lack of water in the trap. If you don't use a drain for two to three weeks, the water may simply evaporate. If you don't use that sink very often, just be sure there is water in the trap.

If that is not the case, check for cracks or breaks in the drain piping. If you don't detect a leak, it could be cracked on top of the pipe.

If that doesn't take care of it, you will need to call a plumber to come check it out for you.

Q: In the last few days, a terrible odor has developed in our powder room. A neighbor suggested that maybe gases are leaking into the room from a pipe.

A: It does sound like you may be smelling sewer gas from your toilet or sink, so I advise you have a plumber come check it out and repair it for you.

To locate a plumbing professional, visit Home Advisor and click on "Plumbing." Submit a service request to repair a small plumbing fixture, and be matched with the ideal service professional in your area.

-- Tips courtesy of HomeAdvisor.com