Glossary
Catalytic converter (CAT)
A catalytic converter (CAT) is an exhaust-mounted device that reduces harmful emissions.
CATs are a high-theft item on cars parked outside; also a common MOT emissions-fail component.
More glossary terms
MOT
The MOT is the annual UK roadworthiness test for vehicles over 3 years old. Here's what it means for a garage.
Class 4 MOT
Class 4 covers most cars and light vans up to 3,000kg. Here's how it affects workshop scheduling.
Class 7 MOT
Class 7 covers goods vehicles between 3,000kg and 3,500kg. Here's what it means for a garage.
DVLA
The DVLA is the UK's driver and vehicle licensing agency. It's the source of truth for reg-based data.
DVSA
The DVSA regulates MOT testing and vehicle standards in the UK. It's the rule-maker your MOT bay follows.
Workshop bay
A workshop bay is one work area — usually a lift or a floor space — that can hold one vehicle at a time.