A vapor cloud and fumes that people in the area said smelled like chlorine were reported at the Diamond Chemical Company around 1:30 p.m.
Homes and businesses were evacuated in the area surrounding Diamond Chemical, located at the corner of East Union and Dubois Street.
Shelters-in-place advised on the east side of Rutherford from Ridge Road to Meadow Road and in Lyndhurst east of Orient Way were lifted around 5 p.m., when air quality readings came back negative.
The incident brought firefighters, at least two ambulances and a hazardous materials unit to the plant.
Chlorine is among the many chemicals used by the plant to make several products, which is what residents smelled when the chemical reaction reached the air, fire officials said at a news conference.
Motorists were urged to avoid the East Rutherford area on Route 17. The northbound lanes in the area were temporarily shut down.
Rutherford police urged residents on the east side of their town to close their windows and take refuge in a small, preferably windowless room out of an "abundance of caution," East Rutherford police said.
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