BATH — Colleagues say that a Bath Iron Works maintenance worker, who was injured Monday afternoon while changing a tire, made it through surgery and is in stable condition at Maine Medical Center in Portland.

Don Bowen, chief steward for BIW’s largest production union, Local S6, said the 40-year-old worker was changing a forklift tire at the northern end of the shipyard when the tire exploded.

“He made it through surgery (Monday night) and he’s stable,” Bowen said. “But as his doctors have told us, the next 48 hours are critical.”

The worker’s identity is being withheld until all of his relatives have been notified. Spokesman Jim DeMartini issued a brief statement today on behalf of the shipyard that said, “Our thoughts and concerns are with the employee and his family.”

DeMartini said the accident, which remains under investigation, took place around 1 p.m. The worker was treated at the shipyard and transported by ambulance to Maine Medical Center.

Bowen said investigators from the Occupational Safety and Health Administration arrived in Bath late today.