By Laura Sanicola

(Reuters] – A unit at Cenovus’ Lima refinery in Ohio, 185,000 barrels per hour, caught on fire Thursday, Cenovus stated to Reuters.

Cenovus reported that injured workers were seen by Cenovus and allowed to return to work after being treated on-site.

We are currently conducting an extensive investigation. We want to ensure we understand what happened and the steps we can take to make sure it doesn’t happen again,” the company said in a statement.

Cenovus employs non-union contractors in the multi-unit turnaround of the refinery, as per the local building trades union.

Cenovus declined to comment on the cause of the fire and what it was.

Ohio unions have been actively gaining political support in advance of the turnaround.

Mike Knisely was the Ohio State Building and Construction Trades Council’s secretary and treasurer. He said this earlier in the week that he supported state legislation which would have stricter requirements regarding contractors who work at high-hazard locations like refineries.

Knisely explained that this incident “reaffirmed all I had spoken about earlier in the week regarding the hazards of working in petrochemical facility… The legislation would have a tremendous impact to eliminate such things,” Knisely.