A refrigerant leak briefly cleared Fair Lawn High School Monday morning.
The Freon leak, discovered around 8:30 a.m., was traced to an HVAC unit on the roof, which "caused a smoke condition on the second floor," one responder said.
The building was ventilated and the all-clear was given to return shortly after 9 a.m.
No injuries were reported.
Fair Lawn police and firefighters were among the responders.
ALSO SEE: A battery on a piece of construction equipment in a Fair Lawn warehouse exploded Monday night, sending a worker flying, authorities said.
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