Find out if you've entered the Clean Air Zone

We have information that will help you determine whether you've entered the Clean Air Zone (CAZ). 

You can:

• find out how the zone is sign-posted
• view a map of the Clean Air Zone (CAZ) boundary
• use our map to search for addresses you may have visited or streets you drove on

If you contact us, we'll aim to help you retrace your route using a series of prompts and the CAZ boundary map to plot likely routes you may have taken.

How you can tell if you've entered the CAZ

Before reaching the zone, advance warning signs are on the main routes to inform drivers there is a Caz ahead.

At the entry points to the zone there are restriction signs. You can view images of these on the CAZ Sign Inventory.

Within the zone, there are also signs to remind drivers they have entered a CAZ. Here is an example of the sign.

You can see GOV.UK: Rules for motorists for more detail about traffic signs and rules.

Why we can't tell you if you've entered the CAZ

We're unable to confirm whether an individual contacting us about a Vehicle Registration Mark (VRM) is in fact the registered keeper of the vehicle. 

Sharing this information could identify an individual and details of their location. This would lead to a data breach and potential safeguarding issues.

We will however always aim to help an individual to retrace their route and have a series of prompts to plot likely routes they took from A to B. This includes using the online CAZ boundary map.

Vehicle Registration Marks

Under the Data Protection Act 2018, we and the Driving and Vehicle Licensing Agency (DVLA) are unable to provide information using a VRM to confirm whether a vehicle has entered the CAZ.

Automatic Number Plate Recognition

Automatic Number Plate Recognition (ANPR) data is personal data. 

It doesn't necessarily identify a living individual, but the vehicle registration plate number is a unique identifier. It could be used, with additional information or knowledge, to make someone more identifiable.

The VRM is captured on an ANPR system that records:

• images
• details of the time / date
• which cameras the vehicle was captured on

It records no other information. This ANPR system then links into the central government CAZ national exemption and payment systems, plus our local exemption lists, but not DVLA keeper information.

We don't receive details of who the registered keeper is until after the daily charge payment has ended and the camera evidence has been reviewed. A Penalty Charge Notice can then be issued.