Bus drivers in the city are still keeping their vehicles running while waiting despite a crackdown on idling engines - but the council behind it says it remains 'confident' the scheme will tackle air pollution.
In October, Norwich City Council confirmed they would have enforcement officers out to speak to drivers in the city centre with engines idling.
If, when asked, they refused to switch off engines, they risked a £20 fine.
While it won't impact drivers in traffic, it will affect those waiting to pick up children or passengers, including buses.
On Thursday, three weeks on, we visited Castle Meadow - one of the worst areas for air pollution - to count the number of buses leaving engines on while picking up and dropping off passengers.
In half an hour, of those that waited at least 90 seconds, 11 switched off, while another 14 kept their engines running. One, which had a 'not in service' label, kept its engine running for six minutes.
Jeremy Cooper, managing director of Konectbus, said their drivers supported 'this very reasonable initiative'.
'Buses are integral to our growing city to improve access, and reduce both congestion and total emissions,' he said.
It was echoed by Chris Speed, head of operations and engineering at First Eastern Counties, who said their buses were fitted with a system which would switch the engine off if a bus was stationary and out of gear for three minutes.
MORE: Norwich drivers could face £20 fine if they refuse to turn off idling engines
But he said it was more complicated than it may appear.
'This obviously helps with improving air quality and compliance with environmental policy within the city, but our drivers do also have a duty of care towards passengers travelling with us, especially in the cold weather,' he said.
'Passengers regularly ask our drivers to put the heating on if the bus is cold, this means starting the bus back up to get the heat to flow around the bus.
'In addition to this, the bus also needs to be switched on to activate the step which lowers to kerb level, allowing easy access for the elderly, people with disabilities and pushchairs.'
While the city council could not yet provide figures on whether any fines had yet been issued, they said it was important thank those who had listened to the plea.
'Switching off engines while waiting may seem like a small action, but it does make a difference,' they said.
They said signs, posters and enforcement officers were in places were emissions were highest, and they remained 'confident' that the continued work would mean that 'very soon it will become second nature to drivers'.
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