Workers were working on a roof of the hospital on Old Hook Road in Westwood when the incident occurred, sickening several people.
Police, firefighters and a Bergen County hazardous materials unit were summoned just after 12:30 p.m. Ramsey Rescue sent the decontamination unit in case any workers or others were exposed to the chemicals.
Ambulances were also put on standby before it was determined that evacuations weren't necessary.
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