Keith Stiles was left unconscious for three weeks after being consumed by the fireball which ripped through the trains at the Paddington rail disaster.

He is now home with his family in Reading again, but he has suffered 70% burns and is badly scarred.

Keith, a technical manager for London Underground, was on the board the Cheltenham express service which collided with a Thames train on October 5.

The tragedy, which happened after the Thames train passed through a red signal at Ladbroke Grove in west London, left 31 people dead.

Mr Stiles told the BBC: "When I heard the bang, I knew immediately it was a serious incident. My first thought was that people might be dead.

"Immediately the train came to rest, I looked up and saw a fireball coming towards me."

His wife Shelagh says she feared he would die, and still thought he would not come through the tragedy alive after he had spent three weeks unconscious.

Mr Stiles still wears bandages on his face and arms and specialists at the Chelsea and Westminster Hospital are monitoring his progress closely.

"Things can't be the same - I am heavily scarred and my face is badly burned," he said. "It is really a case of learning to get on with life."

But with Shelagh's support he is confident he can face the future with optimism.

And consultant Bruce Bhilp at the hospital praised his courage. "He is very positive. He is an example to everyone else."

Mr Stiles called on the authorities to make sure the tragedy is not repeated.

"I would hope that lessons are learned. I would not like to think that the same thing could happen again."

Relative's anguish

Len Northcote, however, is not looking forward to such a bright future.

His son John, a computer programmer working in Slough, was killed as he travelled on the Thames train.

Mr Northcote said: "People are rightly happily getting ready for Christmas but for me it's devastating. Our Christmas just won't be the same.

"There's a numbness just going through the motions of everyday life with no point to it.

"You tend not to be happy; you laugh because you have to but it doesn't mean anything to you."

Mr Northcote said money should be found to improve safety and ensure that the Paddington tragedy could not happen again.

He said: "I think that me and other families, they will find a little bit of comfort that their son or daughter's life hasn't been in vain, that something is going to come out of this.

"But I would like to see someone taken to account for what has happened to these people's lives. I know the safety aspect is very important but I would like to see someone pay for my son's life."