BALTIMORE - Hours after last Friday’s explosion and fire at the Domino Sugar Corp. refinery, the plant’s employees didn’t know when the downtown manufacturing facility would resume normal operations.

What the workers did know, though, was the sooner the plant was cleaned and repaired, the sooner they would be back on the job. Because of the collaborative recovery efforts of the plant’s 500 employees, the refinery was back up and running on Thursday afternoon.

“It is impossible to understate the importance of this accomplishment,” Stuart FitzGibbon, the refinery’s manager, said Friday at the Baltimore Museum of Industry.

The plant resumed operations less than a week after an explosion in a confectionery sugar system on the plant’s eighth floor and a fire in a dust collector on the sixth floor caused what FitzGibbon estimated to be “tens of millions of dollars” in damages. No one was significantly injured in the blast, FitzGibbon said.

The cause of the explosion and fire, as well as whether the two events are related, is still under investigation, FitzGibbon said. “It’s not a simple matter. We don’t know yet.”

Plant managers and employees met last Friday evening after the explosion and decided to immediately start the cleanup process.

Beginning that Friday night, plant employees volunteered to work 12 to 16 hours a day removing all of the plant’s inventory, cleaning the facility from top to bottom and repairing production equipment.

Mark Folderauer, president of the local branch of the United Food and Commercial Workers union, said he didn’t think the plant would resume operations so quickly.

The workers were doing everything they normally wouldn’t do as part of their normal jobs, including hauling debris, Folderauer said.

“It’s our livelihood. It’s our second home,” he said.

The facility passed a Food and Drug Administration inspection on Thursday.

Jim Cochran, a plant engineer manager, said most of the workers believed resuming operations a week after the explosion was an “aggressive but attainable goal.”

“It was a roller-coaster ride. We met each challenge, regrouped and moved to the next challenge,” Cochran said. “The teamwork was incredible.”

The Domino Sugar refinery supports more than 1,000 direct and indirect jobs and is a significant contributor to Baltimore and Maryland’s tax base, FitzGibbon said.

FitzGibbon spoke Friday with two white-and-yellow bags of Domino Sugar in front of him.

“These are the first two five-pound bags produced after the recovery,” FitzGibbon said. “I’m going to keep these for a long time.”