An exhaust fan broke, filling part of Dumont High School with neutralized sulfur fumes Monday afternoon, responders said.
Neither the Science Department teacher involved nor any students or staff were injured or exposed in the incident just before 2 p.m., responders said.
Dumont Fire Chief Mark Abdulla called the incident a ventilation issue and not a spill.
Also responding were members of the Dumont Volunteer Ambulance Corps, a Bergen County Hazardous Materials Unit and a New Milford Hazardous Materials team.
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