Berkhamsted has been warned that unless it can cut traffic in its high street the area’s air quality will suffer.
Dacorum Borough Council has been monitoring levels of nitrogen dioxide – caused by car exhausts – in the area.
The authority has already said that levels are above normal in Northchurch – and measures are being taken to cut them.
It says in a report that they are ‘just inside the safe level’ in Berkhamsted.
The report says:“It is clear that without sustained efforts to reduce traffic coming through the town these levels will be exceeded routinely in the coming years. There are no other major sources of these pollutants in the town.”