The total area covered by the Clean Air Zone is approximately three square kilometres. It is situated to the south west of Portsmouth and extends to Portsmouth harbour on its most western side. Running east past the University of Portsmouth and then up along the west of Fratton and Kingston Road to the start of the M275. It then heads down along the A3 past the Cascades and Alfred Road back to Portsmouth Harbour.

The Clean Air Zone is permanently active, including weekends, evenings and public holidays. The affected area is clearly marked with boundary signs showing the letter ‘B’ on a white background.

In addition, there are warning signs with a cloud symbol on blue background on the approach to the CAZ. These warning signs are located so that motorists have the option to take an alternate route to avoid being charged.

Enforcement of the Portsmouth CAZ is done by Automatic Number Plate Recognition (ANPR) technology, utilising 55 cameras within the zone.

The charge for non-compliant taxis and private hire vehicles to enter the Portsmouth CAZ is £10 per day and for HGVs, buses and coaches the daily charge is £50.

The daily charge covers the period from midnight to midnight (not 24 hours from the time of first entering the CAZ). You can enter the Portsmouth CAZ as many times as you like on the day the charge is paid for.

The Portsmouth CAZ charge can be paid up to six days in advance, on the day and up to six days after entering the CAZ.

The Portsmouth clean air zone (CAZ) charge can be paid via the Government website.

For those unable to use the government’s online service, or need help, there is a clean air support number to call: 0300 029 8888. This is available from 8am to 7pm (except bank holidays) from Monday to Friday and Saturday, 8am to 2pm. Call charges apply.

The Portsmouth CAZ charge can be paid up to six days in advance, on the day and up to six days after entering the CAZ.

If the Portsmouth CAZ charge is not paid within the time allowed, a penalty charge notice of up to £120, plus the original CAZ charge for the vehicle, will be issued to the registered keeper of the vehicle.

The Portsmouth Clean Air Zone is rated as Class ‘B’.

This means that the following vehicles are exempt for charges:

• Passenger vehicles
• Motorcycles
• Vans (LGVs)

The Sheffield CAZ Class ‘C’ rating means that buses, coaches and HGVs need to meet Euro 6 emissions standards to avoid being charged while vans, minibuses, taxis and private hire vehicles must meet Euro 6 (diesel) or Euro 4 (petrol) emissions standards.

There are also local exemptions which apply only to Sheffield’s CAZ, including:

• Large motorhomes over 3.5T GVW
• Buses, coaches or minibuses being used for educational school trips
• Vehicles used for community transport
• Non-commercial vintage buses or vintage emergency service vehicles
• If you have a compliant vehicle (or retrofit) on order (and the application is not through the Sheffield Financial Support Measures
• Disabled adapted minibuses, buses or coaches
• Hard-to-replace vehicles
• Specialist emergency service vehicles

The vehicles below are also exempt if they meet Euro 6 emissions standards (diesel) or Euro 4 emissions standards (petrol):

• Taxis
• Private hire vehicles
• Buses
• Coaches
• HGVs

There are also some specific vehicle exemptions

Vehicles eligible for national exemption from charges to drive in any clean air zone include:

• Ultra low emissions vehicles
• Disabled passenger tax class vehicles
• Disabled tax class vehicles
• Military vehicles
• Historic vehicles
• Certain agricultural vehicles
• Vehicles retrofitted with technology accredited by the Clean Vehicle Retrofit Accreditation Service (CVRAS) from the Energy Saving Trust.

Some vehicle types, such as non-commercial vintage buses or horse transporters are exempt for up to 10 days per year. You can apply for the exemption anytime, even if you don’t know the exact dates you will be travelling in the Portsmouth CAZ.

There are also some vehicle types that are exempt for life, such as emergency service vehicles and specialist heavy vehicles.