The barrier smashed through his windscreen and out of the window

Kenneth Farr, 37, from Penarth, south Wales, had taken his young daughter on a trip to buy a garden shed when the accident happened in May 2002.

The barrier at the Asda in Cardiff Bay crashed through his windscreen.

Witnesses who saw the accident said there were strong winds and that may have caused the steel barrier to fall.

The inquest jury heard how shoppers tried to help Mr Farr, an electronics company worker, and his daughter Jessica, three, who was strapped into the back of the family Austin Montego estate and was not hurt.

Kane Germon told the hearing how he heard a crashing sound as he drove into the supermarket and realised the car behind him had been hit by the barrier.

Kenneth Farr "idolised" his three daughters, the inquest heard

He described running to the car and seeing the barrier had smashed through the windscreen and out through the side window.

Mr Germon said: "I could see the driver was seriously injured and that his daughter was in the back.

"I unbelted her and carried her to my car, in a way so she could not see her father.

"I went back to the car and tried to give first aid with the help of instructions on my phone from the emergency services.

"But within a couple of minutes he appeared to draw his last breath".

Mr Germon said it was "very windy" and that may have caused the barrier to swing across the road.

Another motorist Diane Speer saw the moment of impact of the barrier.

How can a visit to a supermarket end with someone losing their life? Mr Farr's widow, Helen

"There was a crashing noise. It all seemed to happen in slow motion," she told the inquest.

"There were really strong winds that day."

The inquest heard that the steel barrier was at the exit of the store and was swung around at night to stop skateboarders and joy riders using the car park.

Mr Farr was a technician with Panasonic at its plant in Pentwyn, Cardiff, and had just received a gold watch marking 20 years' service.

His widow, Helen Farr, 42, said he "lived for their three daughters" - Jessica, now seven, and her sisters Emma, 11, and Hannah five.

Mrs Farr said:" My husband could be summed up by his email address - Ken.dadof3@hotmail.com

"That morning he was going out to buy a garden shed and Jessica asked to go with him.

"He said he would be back in an hour but he never came back.

"How can a visit to a supermarket end with someone losing their life?," asked Mrs Farr. "Ken idolised his daughters, every spare minute was spent with his family.

"Since Ken's death, which was avoidable, pointless and futile, our lives have changed beyond belief.

Before the hearing began Asda expressed its sympathy for Mr Farr's family. It said it no longer used the barriers and urged other retailers to follow suit.

The inquest, which is expected to last three days, is continuing.