A primary school teachers' union has criticised the Government's school transport policy, and said escorts were needed on buses carrying young children.
Ahead of schools reopening on Monday, John Carr of the Irish National Teachers' Organisation (INTO) said: "The Government has not done enough to make sure that all children are safe on school buses."
The regulations governing safety belts mean every pupil now has to have a seat on a school bus, putting an end to passengers either standing up or sitting without wearing a seat belt.
However, a recent Bus Éireann survey showed that one in four primary school children were not wearing seat belts on school buses.
A spokesman for the Department of Education yesterday said all dedicated school transport buses were now equipped with safety belts, and pupils were required by law to wear them.
The INTO said this law alone was not enough to ensure that children put on seat belts on buses, and the union believed the law was not working because no adult was supervising the students.
"As well as individual seat belts, an adult supervisor, in addition to the driver, is a necessity.
"To expect a driver to be responsible for behaviour and the safety of up to 50 infants as well as driving the bus is not acceptable," Mr Carr said.
In response to a recent Dáil question, Minister of State Seán Haughey said the Department of Education had no plans to provide funding for the provision of supervisors on all school buses.
Mr Carr said Mr Haughey was fooling himself if he thought that belts alone would minimise risks.
"He [Mr Haughey] should make a few trips on school buses early in the new year and see the situation for himself. That would lead him to realise that current policy is flawed. Any parent will tell you that infants need help to put on seat belts."
The department said it allocated funding to schools to enable them to employ escorts on school transport services. However, these escorts were generally employed to cater for children with special educational needs who required continuous support.
