Stephen Galsworthy died in the blast

But the HSE said it could be three weeks before they can enter the site to carry out a detailed investigation due to hazardous temperatures.

Five men remain on life-support machines at Swansea's Morriston Hospital and another five are still in general hospital wards.

A third worker, Len Radford, 53, from Maesteg, died in hospital on Monday as First Minister Rhodri Morgan revealed the content of safety talks held with Corus.

After a meeting with company officials on Friday, Mr Morgan said the explosion in blast furnace number five was "unprecedented."

Unexpected blast

"The explosion was unlike any previous explosion," he explained to the chamber at the Welsh Assembly.

"The accident happened after the furnace was being brought up to temperature."

But the first minister's comments came after it was revealed he met Corus bosses in April 2000.

Several inquiries are under way at Port Talbot

South Wales West AM Janet Davies claimed workers from Port Talbot told her the furnace was unsafe.

She passed on the concerns to Mr Morgan who, she said, had also been told of the worries by plant workers.

Corus, which is conducting its own investigation into the incident, maintains the facility was undergoing regular maintenance.

Workers Stephen Galsworthy, 25, and Andrew Hutin, 20, died after the explosion while five who remain in hospital are critically ill.

The company was fined �300,000 at Cardiff Crown Court on Monday after a smaller explosion at its Llanwern plant last year left a worker paralysed below the chest.