Petrol-engined vehicles: Vehicles powered by petrol that were first registered before January 1, 1973, are exempt from the MOT emissions test.
Diesel-engined vehicles: Diesel-powered vehicles first registered before January 1, 1980, are exempt from the MOT emissions test.
Electric and hybrid vehicles: Electric and hybrid vehicles are generally exempt from the MOT emissions test, irrespective of their age.
These exemptions are in place because older vehicles may not have been designed with emissions controls in mind, and testing them using modern standards may not be appropriate or reflective of their original design capabilities. However, it's worth noting that some local authorities may enforce additional emissions regulations, so it's advisable to check with your local council or authority for specific requirements in your area.