The 15-year age limit was brought in following the deregulation of the bus industry in 1986, with Mr Scales acknowledging in a Merseytravel report “there was concern at that time aged vehicles would be used in school contracts and they might not have been to an acceptable standard”.
But he stressed the “world has moved on” and progressed with the acquisition of predominantly single-deck buses.
The once readily-available surplus of double-decker buses is also no longer available.
This is proving so problematic some school contractors are resorting to sending two single-deck buses, which Mr Scales said is “clearly a more expensive option”.
He added: “There are a number of double-deck buses in the area which are approaching 15 years old and, if adequately and sufficiently maintained, would fulfil a role in school bus contracts.”
But Ian Andain, chairman of Liverpool Schools Forum and head at Broadgreen International School, said “a large number” of the region’s heads “would be concerned about reliability and safety”.
He added: “All school buses cannot be brand new, but to extend the period for vehicle use like this is beyond the pale as far as I am concerned.”
Steven Peach, head teacher at The Oldershaw, in Wallasey, where 50% of pupils catch a school bus, said: “Profit should not come before children’s safety, and vehicle checks would have to be stringent.”