The FTA has poured cold water on suggestions that operators could perform annual roadworthiness tests on their own vehicles.
Allowing operators with testing facilities to carry out MOTs on their own vehicles and those they maintain on behalf of others is a measure supported by the RHA and British Vehicle Rental and Leasing Association, as a way of improving the testing system.
But James Firth, head of road freight and enforcement policy at the FTA, told the Transport Select Committee recently that such a move was akin to "marking your own work".
He added: "FTA members have expressed caution about operators testing their own vehicles, also testing a vehicle they have maintained."
The committee, which is currently scrutinising the workings of Vosa, heard anecdotal evidence of operators facing lengthy journeys or waits of up to three months to get a test slot at some of the 300 authorised testing facilities (ATFs) due to a shortage of Vosa testers.
RHA director of policy Jack Semple said it was "just a short step" for good operators already maintaining vehicles throughout the rest of the year to do the annual test.
He dismissed concerns raised by some committee members that it would lead to corner cutting.
He added: "A haulier has an enormous amount to lose by abusing the system - his own vehicle and good repute as a haulier would be under threat.
"He is already maintaining the vehicle 364 days of the year; what we're talking about is him maintaining it for the 365th day."