The worker suffered injuries that included inhalation burns when he apparently was splashed by hydroflouric acid while hooking a hose to a vat at Diamond Chemical Company on Dubois Street off Union Avenue near Route 17, responders said.
A medical chopper flew him to St. Barnabas Medical Center in Livingston.
Diamond Chemical, which has a 150,000-square-foot complex on 12 acres, makes cleaning and sanitizing products for various industrial and institutional uses -- including laundry, housekeeping and sanitizing.
It includes what the company describes as a state-of-the art laboratory staffed by a "full complement of highly qualified chemists."
NOTE: The incident initially was incorrectly characterized as an explosion.
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