I'm no idler. Switch off engines for cleaner air.

Tackling vehicle idling

Traffic is one of the major causes of air pollution. Reducing emissions from road transport and avoiding idling whenever possible is why we're calling on Merton's drivers to switch off their engines for cleaner air.

Pledge your support or get involved

Idling is where drivers leave their vehicle's engine running while it is stationary.

‘Engine off every stop’

Switching your engine off reduces the emission of harmful pollutants.

Watch this YouTube video – it explains it all

By turning off your car you can:

  • improve the air quality inside and outside your car
  • reduce pollution
  • make our streets and level crossings nicer places to walk and cycle around

We are a partner borough in the Engine Off Every Stop campaign against vehicle idling, which is supported by The Mayor of London. Visit the Idling Action website for further information.

Idling myths and truths

Myth "If it's cold outside, I need to keep my engine running to keep the heater on."

Truth: If you switch the engine off but keep the ignition on, the heater should stay warm for up to 30 minutes.

Myth "If parked on a yellow line, keeping my engine running means I won't get a parking fine."

Truth: Traffic wardens can fine you for parking somewhere illegally, whether your engine is running or not.

Myth "Isn’t it better to idle because stopping and starting the engine will wear it out?"

Truth: This is no longer a problem with modern engines and by not idling you will use less fuel and reduce your fuel costs.

Myth "Idling does not contribute very much to air pollution in the grand scheme of things?"

Truth: Research has shown that switching off engines when parked can reduce air pollution levels in the street where the vehicles are parked. Turning off an engine and then restarting after a minute will cause less pollution than letting it run.

Idling facts

  • Every minute, an idling car produces enough exhaust to fill up to 150 balloons with harmful chemicals, including cyanide, nitrogen oxides (NOx) and tiny particulates called PM2.5.
  • An idling engine burns fuel less efficiently than when the vehicle is moving and so produce more emissions than when travelling.
  • The toxic gases produced by idling are all emitted in the same place, so localised air pollution is higher.
  • Too much idling can damage your vehicle.
  • Turning off an engine and then restarting after a minute will cause less pollution.
  • Even modern diesel engines don't need more than a few minutes to warm up in cold weather.
  • Idling for an hour can waste half a gallon or more of fuel.

Health facts

Long-term exposure to air pollution reduces life expectancy, mainly due to cardiovascular and respiratory diseases and lung cancer.

Short-term exposure to elevated levels of air pollution can also cause range of health impacts, including effects on lung function, exacerbation of asthma, increases in respiratory and cardiovascular hospital admissions and mortality.

According to the Royal College of Physicians, air pollution can cause organ damage and is linked to 40,000 premature deaths a year, with car idling being a contributing factor.

Children and the elderly are particularly vulnerable, as are people with existing conditions such as asthma and other lung complaints. Children’s growing lungs are particularly vulnerable to air pollution, it is thought pollution could be responsible for15-30% of new cases of childhood asthma.

What we are doing

  • We have installed around 250 anti-idling signs at key locations such as  schools, taxi ranks and level crossings and will continue to install them near sensitive areas
  • We are training council staff, councillors and residents to support anti-idling events in the borough
  • We attend local events increasing awareness of idling-related pollution across the borough
  • Working with schools as part of a coordinated London-wide scheme tackling idling, called Idling Action. Much work is ongoing with schools to educate children about air pollution and idling, and to promote active travel to reduce vehicle use for the 'school run'
  • Consulting on school streets.  Roads outside some schools are suitable for school streets which are designed to restrict motorised vehicles at school drop-off and pick-up times. They help to provide a cleaner, safer and healthier environment for everyone
  • Helping businesses to review their travel policies. Businesses are encouraged to reduce business travel where possible and to promote alternatives to using private vehicles for commuting
  • Raising awareness of business-related idling. Providing fleet training for businesses through our Idling Action London membership
  • Reducing the impact of the council fleet. The Council is aware of the need to reduce its own impact in the environment and has strict emissions clauses in its procurement documents

How you can help

  • Cut down your use of motorised vehicles – research has shown that drivers and passengers inside cars are more at risk than cyclists and pedestrians, even on busy road, as they are closer to the exhaust of the car in front.
  • Change your vehicle to a move environmentally friendly option
  • Use more public transport
  • Choose to walk or cycle
  • If you must drive, switch off your engine if you are stationary for more than a minute
  • Consider what your business can do to reduce its air pollution impact – in doing so you could promote a more active lifestyle for your employees

Idling Actions #EnginesOff campaign asks businesses to pledge that their drivers and other employees will not leave their engines on when parked.  As part of the #EnginesOff pledge, Idling Action is offering London drivers free training and is providing a toolkit of resources to businesses whose operations involve vehicle fleets, professional drivers, or employees who travel by car to work.

Report idling vehicles

If you see vehicles idling somewhere on a regular basis please let us know as it will help us to build a picture of idling hot spots in the borough. This will help us with targeting action and using our resources as best we can.

Email us at with the location, type of vehicle and time of day.

Volunteer at upcoming idling action days

Idling action events are held regularly throughout the year. Volunteers provide idling information and leaflets to encourage idling motorists to switch their engines off. These events produce very positive results as having direct conversations is one of the most effective ways of tackling idling. There's always a fun and friendly atmosphere.

Full training and materials will be provided. For more information contact

What more can be done to reduce exposure to air pollution?

Related information