Drivers in Lambeth who leave their engine running while stationary will face a £20 fine in new measures to improve air quality.
The council has launched an idling awareness campaign in a bid to stop harmful engine fumes going into the air unnecessarily.
From Monday 18 May, drivers who allow their vehicles to run while parked will be asked to turn their engines off – if they fail to do so they will be slapped with a fine.
The council identified a series of idling hotspots across the borough – Waterloo, the South Bank, central Brixton, Clapham and the Vauxhall Gyratory.
Outside schools, hospitals, taxi ranks, and coach bays were also flagged as "key locations for idling offences".
Cllr Claire Holland, Lambeth's deputy leader and cabinet member for sustainable transport, environment and clean air, said: "Cleaning up toxic air is an absolute priority for this council.
"Poor air quality is a huge health risk to our residents, and engine idling is a major contributor.
"We are determined to tackle the issue and are confident these new measures will help encourage people to change their behaviour so that everyone in Lambeth – particularly young children due to the effects on their development – is able to breathe clean air."
Between February 2018 and September 2019 wardens in Lambeth asked 2,044 drivers to switch off their engine while stationary – 2,017 drivers complied and 27 people refused.
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