Edgefield County sheriff’s Cpl. Robbie Harter said the industrial explosion at the facility was reported about 9 a.m.
TranTech makes manifolds, headers and valves at its 126,000-square-foot facility at 1 Tranter Drive.
EMA Director Mike Casey said two employees were critically injured and sustained third-degree burns. They were taken by ambulance to the Joseph M. Still Burn Center at Doctors Hospital in Augusta.
A small fire resulted from the explosion, he said, but the cause of the explosion has not been determined.
Lesia Kudelka, communications director for the South Carolina Department of Labor, Licensing and Regulation, said the South Carolina Occupational Safety and Health Administration is evaluating the situation to determine whether it will open an investigation into the accident.