The worker injured in a fire at Syncrude's oilsands facility north of Fort McMurray is still in an Edmonton hospital one week later.

The employee is in stable condition, Syncrude spokesperson Leithan Slade said Monday.

The company said it will not release any further updates about the worker's condition at this time, or say whether the employee's health has improved since the accident, citing concerns for the worker's privacy.

On the afternoon of March 14, an explosion and fire shut down Syncrude's Mildred Lake oilsands upgrader.

The company determined that the fire was caused by a leaking naphtha, or light oil, line, in the upgrader's hydrotreating area. The fire was isolated and extinguished early Thursday.

Syncrude said Monday that only essential personnel can access the fire scene while Occupational Health and Safety staff investigate.

Syncrude declined to share specific details about how the fire has affected production at the site, but it said several upgrading units remain idle or are running at reduced rates.

Consequently, bitumen mining at the Mildred Lake and Aurora Lake facilities has slowed to match the decreased demand from the upgrader, Syncrude said.

Pete Potipcoe posted this video on Facebook of a fire burning at Syncrude's Mildred Lake oilsands upgrader. 0:20

Alberta Labour spokesperson Trent Bancarz said the department opened an Occupational Health and Safety investigation on Saturday and investigators have taken control of the site where the fire happened.

"It's to determine what happened," Bancarz said. "It's to determine what possibly caused the mishap and also what may be done in the future to prevent something like this."

Bancarz said Occupational Health and Safety has two years to complete its investigation and its report will be made public.

The Alberta Energy Regulator is supporting Occupational Health and Safety in its investigation.

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