‘Clean Air Scorecard’ 2024

Clean Air’ Scorecard 2024

Clean Air in London’s (“CAL’s”) final scorecard for the Mayoral and London Assembly elections on 2 May 2024 has been published here:


CAL has previously scored the manifestos of the leading candidates for Mayor of London in a Clean Air Scorecard for the elections in 2012, 2016 and 2021. This is our fifth mayoral election since being founded in 2006.

The Clean Air Scorecard has judged manifesto policy commitments in 2024 under six key headings (and 17 policy themes):

  1. Leadership on clean air – 2 points
  2. Build public understanding of air pollution and climate change including mitigation and adaptation – 2 points
  3. Diesel-free by 2030* – 2 points
  4. Promote active travel including pedestrianisation backed by public health campaign – 1 point
  5. Zero air emissions from buildings, renewable energy and banning incinerators – 2 points
  6. London will be the first vegetarian megacity by 2030 (with progress by 2028)** – 1 point

Our Clean Air Scorecard 2024 is our toughest yet because of the urgent need for bold action to address the public health and climate emergencies. Please remember that the World Health Organisation slashed its air quality guidelines on 22 September 2021 to save millions of lives.

*with limited exceptions

**success would be 51% vegetarian menus and people identifying as wholly or mainly vegetarian (or vegan) by 2030.

Penalty points have been deducted for backward steps on current pollution measures e.g. proposals to scrap the Ultra Low Emission Zone in Outer London.

Watch the short film about the Clean Air Scorecard:



Simon Birkett, Founder and Director of Clean Air in London, commented:

“Clean air is one of the top three issues for the London Mayoral election 2024. Our Clean Air Scorecard, for our fifth mayoral election, is the best way we can judge the candidates fairly against the urgent task ahead.”

“This election has produced the best and worst policies ever from candidates. But it has also produced a clear winner. Zoe Garbett and the Green Party thoroughly deserve their eleven out of 10. Sadiq Khan’s excellent 9/10, in second place, is important for anyone worried about ‘first past the post’ voting for Mayor. Voters have three votes – one for the Mayor and two for the London Assembly.”

“Clean Air in London reminds Londoners that Mayor Khan decided to expand the ULEZ to Outer London after the World Health Organisation slashed its air quality guidelines in September 2021. We need more ambition for clean air, not less, from the next Mayor of London.”

First – Zoe Garbett, Green Party (11/10)

“In every category, Zoe’s manifesto has smashed our toughest and most important Clean Air Scorecard in five Mayoral elections. Her manifesto is inspirational, energetic and extremely detailed.  It unambiguously includes everything in our Scorecard.  Zoe wins a bonus point for engaging positively with the Clean Air Scorecard.  Eleven out of 10.  Lost for more words.”

Second – Sadiq Khan, Labour (9/10)

“Sadiq’s manifesto is visionary for clean air.  It demonstrates a passionate commitment to cleaner air, backed by lots of detail.  He drops points for rejecting pay-per-mile, which could improve current ‘blunter’ congestion and emission charging, and not pledging a ‘diesel-free’ London by 2030.  But he then wins a bonus point for the resolution in his words after we awarded him an ‘A’ for his clean air achievements between 2021-2024.  Nine out of 10.”

Third – Rob Blackie, Liberal Democrats (6/10)

“Rob’s manifesto focuses on other issues. His score benefits from the Lib Dems’ national leadership, with the Green Party and the Labour Party, on a new Clean Air Act – Ella’s Law – that would enshrine the human right to clean air precisely and explicitly in UK law and include a pathway to comply with the WHO’s new air quality guidelines (published in September 2021). His manifesto is light on clean air detail. It won’t move the dial for cleaner air.  Six out of 10.”

Four – Susan Hall, Conservatives (Minus three)

“This is a ‘Car is king’ manifesto not one for cleaner air in a world leading megacity. It’s clear on negatives for air quality, such as scrapping ULEZ expansion, but vague and lacking commitments on potential ‘positives’. Our analysis shows average concentrations of nitrogen dioxide (NO2) monitored in outer London reducing significantly in the first six months following ULEZ expansion, so where’s the evidence for Susan’s claim that “The ULEZ expansion has only had a negligible effect on air pollution in outer London…”? Pledging to scrap the ULEZ expansion gets ‘Minus two’. Susan’s ‘High Pollution Hotspots Fund’ is reminiscent of Boris spraying ‘glue’ in front of air pollution monitors before the Olympics. In total, ‘Minus three’ out of 10.”



Scorecards in 2012, 2016 and 2021. See also our detailed manifesto in 2012.

Green Party – Zoe Garbett, Mayoral candidate


Labour – Sadiq Khan, Mayoral candidate


Liberal Democrat – Rob Blackie, Mayoral candidate


Conservatives – Susan Hall, Mayoral candidate


Nitrogen dioxide (NO2) monitoring data in Outer London (as at 24 April 2024)

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