Hannah Tanhai said the family had suffered greatly

Luke Tanhai, 13, died of head injuries in September last year after he had been hanging on the outside of a bus.

On Tuesday, a jury at Cardiff Crown Court cleared driver Colin Haynes, 59, from Cardiff, of causing death by dangerous driving.

Luke's mother Hannah Tanhai said she wanted changes to the bus system.

She said her son's death, and the case of Stuart Cunningham-Jones, who was killed in a bus crash in Cowbridge in 2002, showed that something needed to be done.

"Two boys have died on public buses - something has to be put in place that cannot be ignored," she said.

Losing Luke has ripped us apart in terms of us as a family Hannah Tanhai

"There are many lessons to be learnt from this terrible tragedy."

She said that children who travel on buses should realise they should not "place themselves in situations they know they shouldn't be in".

"And the parents of those children have to look at the situation they are allowing their children to be placed in.

"But I think the responsibility lays mainly with the bus companies."

Luke died near Cardiff High School in the Lakeside area of the city.

Mr Haynes, who was also cleared of careless driving, had driven for more than 200 metres with the teenager hanging onto a rail by the doors of the bus.

Mrs Tanhai said the accident had left the family "totally shattered".

Luke suffered from attention deficit hyperactivity disorder

"Losing Luke has ripped us apart in terms of us as a family," she said.

"I don't think we can ever put our life back together."

The Welsh assembly's education committee has been reviewing school transport.

Its chairman Peter Black said most problems arose from pupils' "poor behaviour".

"I think that we can do things to improve on that," he said.

"We can put improvements in place which are going to give parents more confidence."

John Pockett, director of the Confederation for Passenger Transport in Wales, said driving a school bus posed many problems.

"If you imagine a bus full of 70 boisterous children who have been kept in school all day," he said, "they're let out and there's horse play, there's messing around.

"Driving a school bus is an unenviable task. You're the only adult on it usually, but your main focus has to be the road ahead."

He added that there had to be firm safety guidelines that could be enforced across Wales.

'Difficulties'

"There are 22 local authorities, they are responsible for school transport. Standards do vary, and that's not helpful for bus companies that need to deal with more than one authority."

David Brown, Managing Director of Cardiff Bus, said a "long-term solution" had to be found to the "difficulties that we all face in ensuring that our children travel safely to and from school".

Mr Brown added that the court case had raised a number of issues for transport providers and for society as a whole.

"We look forward to working with the local community, schools, local authorities, the Welsh assembly and others," he said.