The workers were installing new residential gas main at Union County Parkway and Azalea Road in Union at around 8:30 a.m.
They were connecting an existing main to a new one when there was a flash explosion.
One worker was burned seriously to the arms, chest and face area. That worker was rushed to the burn unit at St. Barnabas Medical Center
The other worker sustained less serious injuries. He was treated at the scene and refused to go to the hospital.
A small ensuing gas leak was capped by Elizabethtown Gas workers.
The injured workers were employed by Henkels & McCoy, a private contractor.
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