Stephen Galsworthy, Andrew Hutin, and Len Radford died in the blast

One of the four pumps was out of action due to maintenance and two others had been stopped by safety systems.

For 12 minutes, the remaining pump was only able to supply 55% of the 20,000 gallons of water needed by number five furnace at Corus' Port Talbot plant.

Len Radford, 53, Andrew Hutin, 20, and Stephen Galsworthy, 25, died.

Former energy operations manager Mark Taylor told the inquest at Swansea's Guildhall that reduced water pressure could damage units which cooled the blast furnace, but could not say how long this would take.

Mr Taylor responded to questions from Lloyd Williams, a solicitor representing the families of the three men, saying he believed operating procedures at the time of the explosion were safe.

He also insisted that his department had not been blas� about safety.

Alarms activated

The jury at the inquest also heard from Gary Williams, a team leader at furnace number five, who had been alerted to a problem on the day of the explosion, 8 November 2001.

He said he had been doing paperwork in his office when his phone rang and a colleague told him alarms had activated on a panel.

The hearing heard an assessment of the systems by Mr Williams' team identified something wrong with the pumps and the supply of water.

One of Mr Taylor's team leaders, Martin Curtis, said he should have been told about the work on the transformer.

Mr Curtis told the hearing he would have made sure that the blast furnace team knew about it. He said he was not informed about the work.

Planned maintenance

On Monday, the jury was told that repairs had been carried out on water pumps inside furnace number five on 7 November after one tripped and another cut out under the power of a stand-in transformer.

The usual transformer had been taken out of action for planned maintenance.

The problem with the pumps had been fixed that afternoon but recurred the following day.

The hearing was adjourned and continues on Wednesday.