The Idling Action London project and its expected outcomes align with Camden’s Clean Air Action Plan and our long-term Clean Air Strategy, which seeks to realise the vision for a borough with clean air for everyone. The campaign aims to improve public awareness of the avoidable dangers to health caused by idling petrol and diesel vehicles and encourages drivers to turn off their engines when parked to cut air pollution. The campaign highlights that air pollution is an “invisible killer” and is dangerous for all Londoners. While drivers of some vehicles like ambulances and waste collection vehicles cannot operate without leaving their engines on, all other non-exempt vehicles must not be left idling, and the drivers of these vehicles are the focus of the campaign.

Impacts of idling on public health

Idling vehicles emit pollutants including nitrogen dioxide (NO2) and fine particulate matter (PM2.5), which are linked to asthma, heart disease, chronic bronchitis and cancer. People with respiratory conditions, the elderly, pregnant women and children are particularly vulnerable.

Outdoor air pollution in the UK has substantially reduced in recent years. According to Air Quality in London 2016-2024 Report, average annual roadside NO2 concentrations in London dropped by nearly half (49%) between 2016 and 2023. However, research shows that there are no safe levels of exposure to air pollution. The Royal College of Physicians’ 2025 update report ‘A breath of fresh air: responding to the health challenges of modern air pollution’ estimates that about 30,000 lives will be lost to air pollution in 2025. It is estimated that every year more than 4,000 Londoners die prematurely from long-term exposure to air pollution. The RCP also estimated that the cost of healthcare, productivity losses and reduced quality of life due to air pollution cost the UK more than £27 billion and potentially as much as £50 billion if including wider impacts such as dementia.

This means that it is essential that we continue to reduce pollution from all sources to protect public health and reduce the financial burden on society.

‘Engine Off, Every Stop’ conveys a simple message: simply switching off the engine of a parked vehicle will make an immediate contribution to reducing exposure to unnecessary yet harmful exhaust air pollution.

The campaign, which is expected to reach millions of people across the capital, will ultimately play a part in driving down idling hot-spots and the pollution created by vehicles in London.

Councillor Katherine Dunne, Cabinet Member for Climate, Environment and Transport at the London Borough of Hounslow, said:

“We’re delighted to be working with Camden to jointly lead this London-wide campaign. We’ve set out ambitious targets to slash transport-related air pollution by 2041, and our Air Quality Action Plan has made tackling this issue a priority for our Borough. Raising awareness of the simple changes we can all make in our daily lives, such as remembering to turn engines off while stationary, will help us meet these targets and deliver a cleaner, healthier Hounslow.

“Idling needlessly pumps harmful pollutants into the air, damaging and shortening lives. Just because we can’t always see air pollution, this doesn’t mean it’s not a killer.

“This campaign delivers a crystal-clear message that’s memorable and easy to follow. I hope that this will encourage drivers across London to join us in cracking down on-air pollution by taking one very small, but powerful step – turning their engine off, at every stop.”

Mete Coban MBE, the Deputy Mayor of London for Environment and Energy said:

“Engine idling is unnecessary and significantly contributes to toxic air pollution, harming the health of Londoners. Supporting this campaign through the Mayor’s Air Quality Fund is just one of the ways we are improving air quality, including the Ultra Low Emission Zone, tackling pollution around schools and rolling out the largest zero emission bus fleet in Western Europe, as we work to build a safer, greener London for everyone.”

 

  • This round of the Idling Action London project (April 2024- March 2027) is funded by the fourth round of the Mayors Air Quality Fund and is jointly led by the London Borough of Camden and the London Borough of Hounslow on behalf of 21 London local authorities. The public campaign which commenced in January 2025 has already achieved over 60 million combined impressions across radio, online and other out-of-home platforms. The campaign will be revamped for winter 2025 starting in November.
  • For more information visit the website: Idling Action

 

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