A trial scheme to encourage drivers to switch off their engines when waiting in parked cars is to be expanded.
Teams of volunteers in the City of London have been asking motorists who leave their engine idling to turn it off.
And the programme is now set to be rolled out across some of the capital’s other major districts, including Hammersmith, Camden and Islington.
It is hoped the trial scheme will help to reduce air pollution, which has become a growing concern in the capital.
The squads of volunteers, who include residents and air-quality wardens, will be operating on certain days in pedestrian zones and residential areas.
They will also be sent to patrol areas outside schools and hospitals, as well as other hotspots for engine idling.
Sadiq Khan, London’s recently elected mayor, has been urged to look at more ways to improve air quality in the capital.
One of these includes tackling congestion to help speed up average vehicle speeds.
It is thought lower speeds throughout London could be making the air pollution problem worse.
Early evidence suggests the scheme to tackle idling has already had some success.
Volunteers have reported that most motorists have turned off their engine when asked to do so.
Financed by the Mayor of London’s Air Quality Fund and town halls, the initiative aims to cut unnecessary pollution by altering motorists’ behavior.
Jon Averns, the City of London Corporation’s public protection director, said that vehicles left running can produce a range of chemicals.
He said: “They emit pollutants including nitrogen dioxides and particulate matter, which are linked to asthma, heart disease, chronic bronchitis and cancer. We need to act now.”
Other efforts to help improve London’s air quality include urging people to commute to work on foot or by bike when possible.
Taxi firms, meanwhile, are being encouraged to use lower-emission vehicles.
Mr Khan said: “At a time when nearly 10,000 early deaths are caused each year by breathing in the capital’s poor air, we must do all we can to clean it up now and for future generations.”