Fourteen people have been taken to the hospital after high levels of carbon monoxide were found Wednesday in a building in New Haven and one of them is in critical condition.
The incident happened around 8 a.m. at a Yale-owned building on Howe Street that is under renovation.
Construction workers were using a propane saw to cut concrete and were not using a carbon monoxide monitoring system or proper ventilation, according to New Haven Mayor Justin Elicker.
Since there was no monitoring system, the construction workers weren't able to quickly identify the carbon monoxide risk, Elicker added.
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One person was found outside passed out and was taken to the hospital, officials said. When that person recovered, he told the hospital what he was doing and emergency crews came to evaluate the site.
When the fire department arrived, they said they found the construction workers and high levels of carbon monoxide at the front door. They evacuated the building and the building next door.
Medical evaluations determined some people had high levels of carbon monoxide in their bodies. In total, fourteen people were taken to the hospital with one person's condition being described as critical by the mayor's office.
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The person who is in critical condition was taken to New York.
Nine of the people who were taken to the hospital were alert and active and four university staff in an office next door were taken for an evaluation as a precaution, officials said.
Yale officials said four of those people have been admitted for observation and nine others are being discharged.
The building inspector has issued a stop work order on the building. The Occupational Safety and Health Administration has responded to the scene.
Howe Street has fully reopened to traffic.
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