The potential to fine drivers who keep their engines running while stationary on Norwich streets is being explored by council bosses.
A year ago, Norwich City Council revealed it might consider whether it could use its civil enforcement officers to take action to try to lower pollution levels in the city.
And Transport for Norwich - the city and county council partnership behind projects such as the Norwich Northern Distributor Road - has been looking into how it could enforce the policy in certain streets.
Officers are carrying out research into the potential enforcement powers, what sort of signs would need to be installed and options for how the enforcement would be managed.
The inner ring road of the city is defined as an air quality management area, so, that is likely to be the area targeted if powers are to be used.
If the council does decide to press ahead with introducing fines, it would need to be considered by the Norwich Highways Agency Committee - made up of city and county councillors and by the city council's cabinet.
And it would need an application to the Secretary of State before enforcement could begin.
While the plan would be to stop mainly bus and taxi drivers from running engines, it could be also be used for other motorists in the city centre, for example those queuing for car parks.
Labour city councillor Mike Stonard, vice-chairman of Norwich Highways Agency Committee, said: 'Air quality is an important issue facing cities across the world.
'Working with Norfolk County Council, we want to keep emissions as low as possible in Norwich and an engine switch-off policy is one of the measures that could help.
'Research into the powers available to us as a city council is the next step in deciding whether to take this forward as an option.'
Earlier this year, Norwich South MP Clive Lewis called for cities to be given extra powers to enact clean air zones. The most polluting buses, taxis, coaches and lorries would be charged to enter those zones.
• Do you think fines would be a good idea? Write, giving full contact details, to Letters Editor, Prospect House, Rouen Road, Norwich NR1 1RE or email EDPletters@archant.co.uk
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