The worker was taken to St. Barnabas Medical Center in Livingston by Saddle Brook EMS after the chemical reaction Friday night at Chem Aid Laboratories on Mayhill Street, Police Chief Robert Kugler told Daily Voice.
The flash fire was immediately extinguished, he said.
"A Garfield Hazardous Materials Unit responded and determined no cause for hazmat concerns," the chief said.
The building was occupied by a dozen or so people, he added.
Chem Aid was investigating, Kugler said.
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