In Australasia, school buses over 3.5 tonnes are usually not fitted with seat belts and were not designed to have seat belts fitted. Retrospective fitting of seat belts to these buses is usually not possible for a number of reasons:In the event of a crash, it is unlikely that the seats and flooring of many early model buses could withstand the additional loads exerted if seat belts were fitted.
In some buses, it may be possible to strengthen the underfloor structure to allow at least twopoint seat belt anchorages to be installed, albeit at considerable expense and with dubious safety outcomes.
The optimum distance between seats equipped with seat belts needs to be approximately 85 centimetres. If seats are spaced closer, as is the case in many older buses, the possibility and severity of head, neck and spinal injuries are increased.