The answer to the two problems of diesel polution, fine carbon particles and NOx, is to ban diesels that do not have particle filters and Adblue. This means in effect that Bristol could significantly improve air quality by first banning pre Euro 5 diesels that do not have particle filters and then banning pre Euro 6 diesels that do not have Adblue.

An example is the current list of vehicles prohibited from the centre of Milan

Prohibitions in force

Euro 0, 1 petrol
Euro 0, 1, 2, 3, 4 diesel without DPF
Euro 0, 1, 2, 3 diesel with after-market DPF with particulate mass class lower than Euro 4
Euro 3, 4 diesel with DPF as standard and field V.5 certificate> 0.0045 g / km or no value in the V.5 certificate
Euro 0, 1, 2, 3, 4 diesel with after-market DPF installed after 31.12.2018 and with particulate mass class at least equal to Euro 4
dual-fuel diesel-LPG and diesel-methane Euro 0, 1, 2

Peter

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