CLAYTON, Mo. – A high-rise building was evacuated Tuesday morning in Clayton after a carbon monoxide detector went off in one of the units.

Firefighters tell FOX 2 that they received a call about the issue from the Clayton on the Park building at the corner of Bonhomme and Brentwood at around 6:30 a.m. That call potentially saved lives.

“We had an individual resident that had a store-bought CO2 detector like the kind you get at Home Depot, which actually alerted,” said Clayton Battalion Chief Ryan Harrell. “She notified the fire department. The first crew on scene went ahead and checked her unit and realized it was a bigger problem. We were getting readings throughout the building.”

The 23-story building has about 20 floors of occupied condos. Bommarito Automotive Group SkyFOX was over the scene this morning. Windows can be seen open in the building and people are on the street level waiting for clearance to go back in at around 8:15 a.m.

Firefighters determined that the unit providing heat to the entire building was malfunctioning and sending carbon monoxide to the entire building. Harrell says the highest carbon monoxide readings came from the building’s heating units located on the roof. The building did not have carbon monoxide detectors.

Firefighters say a resident whose carbon monoxide detector went off contacted them. That action may have saved a lot of people from carbon monoxide exposure. Her store bought detector helped alert a lot of people to a potential issue.

Residents tell FOX 2 that the evacuation was orderly and everyone cooperated with orders to get out.

“I’ve been through enough of these where you just get out. That’s what I did.” Said 5th floor resident Joe Simmons.

“One of the maintenance people who works in the building knocked on the door and told us to evacuate the building,” said 20th floor resident Nicholas Sheppard.

“I just wanted to get out because you don’t know what’s happening,” said 8th floor resident Leone Fox.

“The nerves really set in once I found out the situation was a little more grim than I originally thought,” said 10th floor resident Alexander Ebel.

“This young lady who purchased that unit really saved a lot of people today by being able to notify us early,” said Harrell.

Harrell says no one was overcome by the gas or treated for carbon monoxide poisoning. Residents eventually returned to their apartments. He tells us many residential buildings are only required to have smoke detectors, but that’s not always the case for apartments.

If you live in an apartment, he encourages you to buy a carbon monoxide detector for your unit. It’s advice residents are taking to heart.

“It’s kind of a no-brainer to just have one It’s just a really cheap insurance policy,” said Simmons. “I’ve always had one, but this is the only unit I’ve ever lived in where I didn’t have one. I think I’m going to be buying one pretty soon.”