SIR- Bradford's 'controversial' Clean Air Zone (CAZ) will now begin on September 26, 2022 after being delayed. Imagine if the Covid-19 vaccine rollout had been delayed by six months.

To be less controversial, I'd like to suggest a catchy slogan to be used by the clean air campaign that reflects the general public indifference on this issue and may bring more support: "Pollution: The silent killer that never gets a minute's silence".

Alan Bates, Bowland Avenue, Baildon