Expand Highway Code Rule 123 "You must not leave a vehicle's engine running unnecessarily while that vehicle is stationary on a public road", to apply to all roads & open spaces inc. car parks, irrespective of whether they are public or private. National advertising campaign to educate the public.
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The law currently prohibits ‘vehicle idling’ but expanding the Highway Code and a public awareness campaign could help reduce damaging emissions and improve public health. It is common practice for car drivers to park up with their engines running e.g. when taking phone calls, waiting in drop off zones (hospitals, railway stations, schools), delivery drivers, etc. Private roads & spaces to be included as the air polluted at these sites is NOT PRIVATELY OWNED and should not be regarded as such.