Almost 43,000 MoT tests have been cancelled in Northern Ireland since the alarm was raised over structural defects in car lifts at government test centres, according to official figures.
he figures represent a huge surge of more than 35,000 in less than a month as the massive programme of cancellations which began in late January begins to bite.
On January 28, it was reported that the number of cancellations was around 7,000.
Cracks in vehicle lifts were first detected in November 2019, but it was not until January that MoT test centres were forced to close after cracks were spotted in 48 out of the 55 Maha DUO+1 scissor lifts supplied by German firm Maha to Driver and Vehicle Agency (DVA) test centres across Northern Ireland.
The lifting equipment is used to examine the undersides of cars and vans.
Tests cancelled since February 17 are not included in the figures obtained by the Belfast Telegraph, meaning the actual number of cancellations will be higher.
But despite the disruption, the Department for Infrastructure figures revealed that the DVA had managed to carry out 45,000 tests over the period to 17 February - a figure only slightly higher than the number of cancellations.
The scheduled testing of heavy goods vehicles, buses and motorcycles has been unaffected by the current disruption.
Northern Ireland motorists whose tests were cancelled are receiving special exemption certificates which permit them to be on the road legally without an MoT - provided their car is safe to drive.
The certificates will be valid for up to four months after the expiry of the vehicle's previous MoT, and owners will be contacted when a new test appointment becomes available.
SDLP Infrastructure Minister Nichola Mallon has ordered two independent reviews into the MoT crisis.
A spokesman for the Automobile Association said that they had not received any complaints from members in Northern Ireland about how the MoT certification delay was being handled by the authorities.
"The chief concern was that motorists whose MoTs had expired would face difficulties taxing their vehicles, or be caught with an untaxed vehicle on the road - but the authorities in Northern Ireland and Swansea seem to have dealt effectively with that issue," the spokesman said.
"The only other concern we would have is that there is a possibility that some of those 42,000 vehicles with expired MoTs could have serious faults which have gone undiagnosed - and which could be dangerous."
The Association of British Insurers said a motor insurance policy requires that the vehicle is kept in roadworthy condition - and it is the responsibility of the driver to make sure their vehicle is safe to drive and complies with all applicable laws.
An insurer would not penalise a policyholder for something that is entirely out of their control, such as the suspension of MoT test facilities, and would approach any claims on a pragmatic case-by-case basis provided that the policyholder had booked a test, the association said.
The Department for Infrastructure has advised drivers to make their insurance company aware of any MoT test delay and let them know if an exemption certificate has been issued, for their vehicle.