Several UK cities have introduced a #CleanAirZone. Cities with a CAZ fared slightly better in the 2021-2023 period (11% drop ) than those without (5% drop, excluding Sheffield as data not available). Apologies for the small sample sizes, so this analysis should be taken with a grain of salt. #AirPollution #LetPompeyBreathe https://greenpompey.org.uk/let-pompey-breathe/2024/12/19/effect-of-clean-air-zones-on-uk-cities/