Madison, WI – A carbon monoxide leak at an East Side restaurant forced the evacuation of the business Saturday afternoon, but customers were back inside less than an hour later.

Madison Fire Department firefighters were called to That BBQ Joint, 901 Williamson St., at about 4:45 p.m. Saturday, after complaints of an “odd smell” at the restaurant.

Firefighters were on scene in minutes since Station 3 is three blocks away.

Sensors showed slight levels of carbon monoxide in the main level of the building, but the owner told firefighters the smell was coming from the basement.

“Readings spiked to 800 ppm, so patrons were directed to evacuate the building until the carbon monoxide could be cleared out and the source identified,” said spokeswoman Cynthia Schuster.

Madison Gas and Electric was called in after the leak was determined to be coming from the boiler room.

The building was ventilated, carbon monoxide levels went to zero and patrons were let back into the restaurant.