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Tackling idling in Merton

Tackling idling

We're calling on Merton's drivers to switch off their engines for cleaner air.

Pledge your support or get involved

Idling means leaving a vehicle's engine running while it is stationary. Whilst this can often be the result of traffic, there are cases where you should turn your engine off such as:

  • waiting at level crossings
  • waiting outside schools or businesses

‘Engine off every stop’

Switching your engine off reduces the emission of harmful pollutants.

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 facts

  • Every minute, an idling car produces enough exhaust to fill up to 150 balloons with emissions containing carbon dioxide (CO2), harmful chemicals including cyanide, oxides of nitrogen (NOx) and particulate matter (PM).
  • Long-term exposure to NOx can cause airway inflammation, respiratory problems and decrease in lung function, while CO2 significantly contributes to climate change
  • According to the Royal College of Physicians, air pollution can cause organ damage and is linked to 40,000 deaths a year, with car idling being a contributing factor.
  • 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.
  • You do not need to keep your engine running to stay warm - your engine will stay warm for 30-60 minutes after it is switched off.

What we are doing

  • We have installed around 200 anti-idling signs at 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 will launch a school engagement programme in 2020 to raise awareness of the benefits of not idling


You may be exempt from needing to switch off if:

  • you are defrosting a window
  • the vehicle needs to be on for a technical reason, for example if it is refrigerated or is operating lifting equipment
  • you are elderly or unwell and trying to keep warm in cold weather

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.

Get involved

Pledge to stop idling

Pledge to stop idling - fill in the form to pledge your support for our campaign.

Volunteer at upcoming idling action days

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

We run action days throughout the year during which volunteers 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 and full training and materials are provided.

What can be done to reduce exposure to air pollution?

  • Emissions tend to be higher inside the car than out on the street, so it's better to walk or cycle rather than drive
  • Use tools such as the Clean Air Route Finder to choose low pollution routes
  • Sign up to airTEXT for free pollution forecasts