The incident took place Monday, Oct. 25, around 11:30 a.m. when an automatic fire alarm at Warring Elementary in the City of Poughkeepsie alerted firefighters to the problem.
Upon arrival, it was discovered that the building had been evacuated of all children and staff and a manual pull station had been activated due to a haze and there was an alarm sounding, the City of Poughkeepsie Fire Department said.
The building was checked out with multimeters and a carbon monoxide leak was detected.
The furnaces were shut off and the building was ventilated.
One staff member was transported to an area hospital for treatment and seven others were treated on the scene. None showed high levels of carbon monoxide.
Firefighters opened windows in the multi-story building to help with ventilation.
Poughkeepsie Schools Superintendent Eric Rosser said the odor was coming from a boiler, which was fixed, and the building was deemed safe.
During the incident, students were bussed from Warring to Morse Elementary School where they could be picked up by parents.
School officials decided to close the school for the remainder of the day as a safety measure.
The boiler and HVAC systems in all seven district school buildings are scheduled to be replaced over the summer break as part of the district's $98 million capital project.
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