An early morning blaze that shut down a Durban oil refinery on Thursday will not affect petrol supplies despite the refinery's closure, Engen said.

Refinery general manager Willem Oosthuizen said the blaze that had broken out in the refinery's crude unit — the facility that feeds crude oil into the refinery's processing units — would not affect fuel supplies as there was sufficient stock on hand and Engen would secure supplies from abroad.

"Other oil companies also have significant stocks, so we don't expect shortages," he said.

He said that Engen had enough in storage to keep supplies going for the next two to three weeks, by which time ships from abroad would be arriving with further stocks.

Oosthuizen said the blaze would cost the company in the region of US$600 000 (R6.22-million) a day. The refinery is expected to be shut down from between two and four months.

Earlier Engen spokesperson, Herb Payne said the blaze broke out shortly after midnight and had been extinguished by 3.10am by the refinery's own fire fighting team.

He said: "It is not possible to pinpoint the cause of the fire or the cost of the damage at this stage. It is also not yet possible to say what impact this will have on fuel supplies or when the refinery will be back in operation."

The refinery, located in Durban's southern Wentworth suburb, supplies the country with almost 20 percent of its refined fuel.

An investigation is underway to determine the cause of the fire. Air samples that were taken would be sent to laboratories for testing.

Payne said that the city's eThekwini municipal fire brigade had been on standby to offer assistance.

Oosthuizen said at a press conference on Thursday afternoon that the pumps where the fire had broken out had been checked two days previously and were found to be in working order.

Preliminary investigations had also not revealed any breakages in the pipes.

"We still need to find out what caused this fire. It seems it could be pump or seal failure, but that would be surprising because the pump was checked two days ago," said Oosthuizen.

He did not believe that there had been any form of sabotage.

Oosthuizen said that if the facilities could not be repaired, then it would take at least three months before production resumed.

Payne said that effluent used in fighting the blaze had been contained and would be disposed of safely.

In November last year R120-million worth of petrol and equipment went up in smoke at the refinery after a 45 metre high petrol tank containing 7.5 million litres of petrol was struck by lightening.

That blaze continued for nearly three days.

Sapa