The thing about a low-speed bus is there's less chance of a bus being involved in a rollover where children are being tossed around inside the bus. If anything happens, it's probably going to be a frontal impact where the children will come ahead and compartmentalization will contain the children.
In an issue of Bus & Motor Coach News there was an operator in the United States that actually fitted seats with two-point seat belts and it was involved in a collision. Children who weren't strapped in survived and children who were strapped in were killed because of the upper body trauma caused by the seat belts. We have to be careful with that.
Over 50 kilometres an hour on secondary highways where the speed is accelerated to 80 to 90 kilometres per hour, I think the kids should be strapped in and they should be three-point belts.