ExxonMobil’s giant oil refinery in Louisiana is currently operating at planned rates after a fire earlier this week, according to reports.
All refinery units apart from the compressor where the fire occurred are said to be operating normally.
The refinery is the fourth-largest in the US with capacity to refiner 502,500bpd in crude oil.
The fire broke out in a compressor associated with an 18,750-bpd alkylation unit.
Five people were preparing the compressor for restart following repair work and four people are now said to be in a critical condition after the fire, according to Baton Rouge Hospital.
Exxon has said it is investigating the cause of the incident and would not comment on the status of the refinery.
It said the first at the plant was extinguished at about 4pm on Tuesday and the firm had accounted for all staff at the refinery.