MADISON, Wis. -

Madison firefighters helped prevent a potential disaster when they found a natural gas leak in a home Friday morning, according to a release.

Firefighters were preparing to install carbon monoxide alarms in a home on Adobe Way when they smelled natural gas, officials said. Crews used a monitor and found the source of the leak was a valve below the fireplace.

According to the release, the explosive level of the natural gas leak was at 100 percent.

Firefighters evacuated the homeowners, turned off the gas supply to the fireplace and ventilated the home, officials said. MG&E also responded to the home.

Crew members were at the home installing carbon monoxide alarms as part of a Fire Prevention and Safety Grant from the Federal Emergency Management Agency, officials said. Residents interested in receiving alarms can call 608-266-4709.