The accident happened at Swepco Tubing, which makes metal tubes.
Fire officials say a roofing company employee jumped into a vat of nitric acid to save a co-worker who fell 40 feet through a roof and into the tank.
Relatives say 44-year-old Martin Davis suffered a broken rib, punctured lung, and burns on his legs and side. He's in critical condition.
Clifton Fire Chief Vince Colavitti says 51-year-old Rob Nuckols was on the ground floor and jumped into the vat. He was waist-high in acid while he and three others pulled Davis out. Nuckols was treated for burns.
The company's website shows vats used in that process, some which contain acid baths for those tubes. Fire Chief Vince Colavitti says the company was adding a second roof above an existing roof, which was apparently weakened by the chemicals below, when it collapsed, and the worker fell into the vat of acid. A 9-1-1 call brought hazmat units and firefighters.
The acid was reportedly 40 to 70 percent strong.
Swepco declined to comment, but fire Chief Colavitti says the vats contain acid at 40 to 70 percent concentrate. The roofer works for Garcon Enterprises out of Flemington, New Jersey, but no one answered the phone there.
OSHA, the Passaic Health Department, and Clifton's Buildings department are all investigating the accident. The fire department says Garcon Enterprises did not have a permit to do the roofing work.
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