BALTIMORE (WJZ) — Crews are investigating after 13 people were hospitalized after showing signs of Carbon Monoxide poisoning at the Baltimore City Fire Academy.

First responders were called to the academy located in the 6700 block of Pulaski Hwy. for reports of Carbon Monoxide poisoning.

Testing revealed a situation that could have proved potentially deadly.

“Once we were able to assess the building and get in, there were high levels of carbon monoxide our numbers were well over 200 ppm when the normal reading is around 8, anything under 8 ppm,” said Blair Skinner with Baltimore City Fire.

An official with the Baltimore City Fire Department said several people were showing signs of Carbon Monoxide poisoning just after 3 p.m.

The building was evacuated as a precaution, and CO readings showed the buildings had “elevated” CO levels.

Four people were experiencing Carbon Monoxide poisoning symptoms and were taken to a local hospital.

A captain who went home for the day also started experiencing symptoms and was taken to a hospital form his house.

In total, 11 recruits and two administrators experienced symptoms and were transported to area hospitals.

Everyone else who was in the building Thursday is also being evaluated.

The cause of the leak is still under investigation.

“The building has been evacuated and is being ventilated at this time,” Skinner said.

A ventilation process could take all night. Fire officials said it’s lucky it was caught early.

“Carbon monoxide is unpredictable, you know its a colorless, odorless gas and the first sign really is if someone experiences any sort of symptoms related to it,”

Fire officials also reminded the public it can happen at home.

“Would you know about CO exposure in your own household?” WJZ reporter George Solis asked. “I would not,” said Monica Jones, a Baltimore resident.

Donald Makuku said he has several carbon monoxide detectors.

He said it was the city’s awareness campaign that showed him the dangers and convinced him not to take any chances.

“You are not going to smell it, you’re just going to go to bed, take a nap and not wake up, see that’s the most dangerous thing about it,” Makuku said.

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