HOUSTON BP Plc (BP.L) said its largest U.S. refinery, at Whiting, Indiana, continued to operate on Thursday morning following a blaze the night before that was expected to have a minimal impact on production.
One worker was taken to an area hospital for treatment, but was later released, the company said.
BP said operations at the 413,500 barrel per day (bpd) Whiting refinery "were minimally impacted as a result of the incident and the refinery continues to produce products for customers."
The Whiting refinery is the seventh-largest refinery in the United States and the largest outside of the Gulf Coast.
The plant is the centrepiece of BP's shift over the past two years to emphasise using cheaper, heavy crude oil from Canada's tar sands fields in Alberta.
In November, BP completed a $4-billion revamp of the Whiting refinery to boost its intake of Canadian crude oil from 85,000 bpd to 350,000 bpd.
On July 29, BP's Chief Executive Bob Dudley said during a conference call that Whiting had been refining 270,000 bpd in heavy crude oil in the second quarter of this year and could likely run up to 300,000 bpd.
In its statement on Thursday, the company did not specify which unit was affected by the blaze, but said it was located in the north end of the refinery.
BP said the fire broke out at 9 p.m. Wednesday local time (03:00 a.m. BST Thursday). The fire was out by 10:55 p.m. local ( 11:00 a.m. BST) time Wednesday.
Firefighters from the city of Whiting were placed on stand-by to assist in battling the blaze, but the fire was contained and extinguished by BP's firefighting unit at the refinery.
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