Same as any other low emission zone, they would use dedicated ANPR cameras and levy a fine for the cars/trucks/vans that they deem to be dirty based on their manufacturers stated tailpipe emissions.
Shouldn’t affect the scheme at all, the most stringent emissions applied to these zones so far are Euro 6 (2015) for Diesels and Euro 4 (2006) for cars, so all scheme cars are already in the “clean” bracket.
In addition, although not mentioned, it is likely to have an exemption for the disabled – most other low emission zones do.
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