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Clean air is critical care: the healthcare case for action
Air pollution is not just an environmental issue, it is a major health crisis. It affects us from before birth right through to old age, contributing to heart and lung disease, stroke, diabetes and even mental health conditions. This Clean Air Day (19 June 2025), we join partners across the health sector to call for urgent action to clean up the air we breathe, for the sake of our patients, our communities and future generations.
“Air pollution is associated with between 29,000 and 43,000 deaths a year in the UK. The World Health Organization and the UK Government recognise that air pollution is the largest environmental threat to our health“
– Clean Air Day 2025, Global Action Plan
At the Centre for Sustainable Healthcare, we recognise clean air as essential to a healthy environment and a healthy NHS. From redesigning care pathways to creating greener clinical environments, we support healthcare organisations in their journey toward a cleaner, low-carbon future.
Green Spaces: a natural defence against air pollution
Air pollution is now recognised in the UK as a cause of death. Green spaces have the capacity to save lives by combatting air pollution. All vegetation can play a useful role, but trees are particularly effective at improving air quality. Trees provide a shield against various air pollutants, including ozone (O3) and nitrogen dioxide (NO2) as well as carbon dioxide (CO2). By acting as physical barriers they effectively block pollutants from reaching people.Trees with a greater leaf area have the most pronounced effect. Safeguarding our existing mature trees is immensely important as they offer the most protection.
Green spaces cut pollution in urban areas
Research using the UK Tree Equity Score shows that neighbourhoods in the UK with the highest number of trees have up to 33% less air pollution than those with the least tree cover. Areas with high tree cover tend to be more affluent and have fewer people identifying with minority ethnic groups. This shows quite clearly the relationship between neighbourhood tree cover, air quality and health inequalities.
Healthcare sites leading by example
Healthcare facilities are increasingly recognising their role in reducing air pollution, not only through decarbonising operations but also by improving the natural environment around them.
• Great Ormond Street Hospital has embedded clean air priorities into their Green Plan through their Healthy Hospital Street initiative, using street redesign and planting to make the environment safer and healthier for children and families.
• Mid Yorkshire Teaching NHS Trust has developed a dedicated Greenspace Wellbeing Strategy. This includes a comprehensive hedge and tree planting programme that supports clean air goals and complements broader emissions strategies targeting transport and medical gases.
These examples show how green infrastructure can be a core part of healthcare’s climate and health response
The value of trees, in more ways than one
The air quality benefits of trees and green spaces can also be valued. A recent study by Forest Research evaluated the annual value of air quality improvement from trees at a single NHS site and estimated it at £8,595. This is an important consideration when looking at the triple bottom line for green space development on healthcare sites.
Developing green spaces at healthcare sites reduces air pollution. Sites can make significant improvements through planting green spaces and maintaining mature trees.
Tools and resources to support clean air action in healthcare
There are a number of useful tools to help assess and plan green space strategies to support cleaner air. Here is a selection of some of the best:
• The local air pollutant removal value of trees in the UK
• UK Air Interactive monitoring networks map
• Green Infrastructure for Roadside Air Quality
• Nature for Health – A Resource Hub for Healthcare Sites
Ending Entonox Waste project: tackling hidden emissions
In addition to green space action, the Clinical Team at CSH is addressing a critical but often overlooked source of air pollution: Entonox waste. Entonox, a 50:50 mixture of nitrous oxide and oxygen used commonly in maternity care, is a potent greenhouse gas with over 260 times the global warming potential of carbon dioxide. Alarmingly, research indicates that a large portion of Entonox emissions within the NHS are the result of gas leaks, not patient use.
The Ending Entonox Waste project was created to raise awareness and equip healthcare staff with the knowledge and tools to reduce these emissions. The project focuses on identifying leaks in pipework systems, promoting alternative pain relief options, and supporting the use of new technologies like catalytic ‘cracking’ that safely neutralise exhaled Entonox.
This work aligns closely with Clean Air Day’s mission to reduce health-harming pollutants and highlights the unique opportunity for healthcare professionals to drive change from within. By cutting Entonox waste, we not only protect the environment but improve air quality for patients and staff, and reduce unnecessary NHS emissions.
We encourage healthcare professionals to visit the project page, access the expert talk videos, and explore the toolkit to learn how they can take action in their own trusts.
Let’s keep building momentum
Clean air is a public health necessity. Whether through clinical innovation, green space planning or policy advocacy, healthcare professionals are vital to the clean air movement. Let’s make this Clean Air Day the start, or continuation, of meaningful action. Because every breath matters.
Add your voice: a call for health sector leadership
The UK Government is reviewing its air quality targets, presenting a pivotal moment for healthcare professionals to advocate for change.
This Clean Air Day, we’re supporting a joint letter to government, coordinated by Global Action Plan and Great Ormond Street Hospital, urging adoption of the WHO’s air quality guidelines. The letter will be delivered at a London Walk & Wheel event from Great Ormond Street Hospital to Parliament Square.
If you work in healthcare, add your name to the letter and call for action that protects health.
Deepen your knowledge with our Sustainable Respiratory Care course, case studies and network
Our Sustainable Respiratory Care course explores how respiratory healthcare contributes to environmental harm and what we can do to improve it. You’ll gain practical tools to reduce the carbon impact of inhalers, understand greener prescribing principles, and develop more sustainable, high-quality care pathways.
To support action beyond the classroom, we’ve built a library of real-world case studies showcasing successful interventions across the NHS: from switching to lower-carbon inhalers to redesigning patient care models. These case studies offer practical insights and inspiration for clinicians looking to make evidence-based, sustainable changes in their own settings.
We also invite you to connect with peers through our Sustainable Respiratory Care Network, a community of healthcare professionals committed to sharing knowledge, challenges and progress in sustainable respiratory care. The network is a space to learn, collaborate, and stay updated with emerging research and best practice.
