Current Levels

Current measured levels are shown in the table below - showing concentrations and, where applicable, the corresponding index and bands.

Site 8 Hour mean
Ozone
µgm-3
Hourly mean
Nitrogen dioxide
µgm-3
Max 15 min mean
Sulphur dioxide
µgm-3
Running 24 Hour mean
PM2.5
Particles
µgm-3
Running 24 Hour mean
PM10
Particles
µgm-3
Aston Expressway A494 Deeside
Updated: 27/04/2025 10:00
Not measured 21
Low (1)
Not measured Not measured Not measured
Aston Hill
Updated: 27/04/2025 10:00
67
Low (3)
2
Low (1)
Not measured Not measured Not measured
Bridgend Park Street
Updated: 27/02/2025 22:00
Not measured No data Not measured Not measured No data
Caerphilly Blackwood High Street
Updated: 03/12/2024 08:00
Not measured No data Not measured Not measured No data
Caerphilly Fochriw
Updated: 06/01/2025 22:00
Not measured Not measured Not measured No data No data
Caerphilly Islwyn Road Wattsville
Updated: 27/04/2025 08:00
Not measured 4
Low (1)
Not measured Not measured Not measured
Caerphilly White Street
Updated: 27/04/2025 07:00
Not measured 9
Low (1)
Not measured Not measured 14
Low (1)
Cardiff Castle Street
Updated: 25/04/2025 09:00
Not measured No data Not measured 10
Low (1)
21
Low (2)
Cardiff Centre
Updated: 26/02/2025 09:00
No data No data No data No data No data
Cardiff Newport Road
Updated: 27/04/2025 10:00
Not measured 7
Low (1)
Not measured Not measured 15
Low (1)
Chepstow A48
Updated: 27/04/2025 10:00
Not measured 19
Low (1)
Not measured 11
Low (1)
19
Low (2)
Cimla Road / Victoria Gardens
Updated: 28/06/2024 09:00
Not measured No data Not measured Not measured Not measured
Cwmbran Crownbridge
Updated: 27/04/2025 10:00
42
Low (2)
3
Low (1)
Not measured Not measured 12
Low (1)
Hafod-yr-ynys Hill Roadside
Updated: 27/04/2025 10:00
Not measured 14
Low (1)
Not measured Not measured Not measured
Marchlyn Mawr
Updated: 27/04/2025 10:00
No data 1
Low (1)
Not measured Not measured Not measured
Nantgarw Road
Updated: 27/04/2025 09:00
Not measured 13
Low (1)
Not measured Not measured Not measured
Narberth
Updated: 27/04/2025 10:00
65
Low (2)
2
Low (1)
1
Low (1)
5
Low (1)
8
Low (1)
Newport M4 Junction 25
Updated: 27/04/2025 10:00
35
Low (2)
30
Low (1)
Not measured Not measured Not measured
Newport M4 Junction 25 West
Updated: 27/04/2025 10:00
Not measured 6
Low (1)
Not measured Not measured Not measured
Newport St Julians Comp School
Updated: 27/04/2025 10:00
Not measured 4
Low (1)
Not measured 11
Low (1)
14
Low (1)
Port Talbot Dyffryn School
Updated: 27/04/2025 09:00
Not measured Not measured Not measured 6
Low (1)
9
Low (1)
Port Talbot Little Warren
Updated: 27/04/2025 10:00
Not measured Not measured Not measured 9
Low (1)
12
Low (1)
Port Talbot M4 Junction 41
Updated: 27/04/2025 10:00
Not measured 7
Low (1)
Not measured Not measured Not measured
Port Talbot Margam
Updated: 27/04/2025 10:00
51
Low (2)
7
Low (1)
2
Low (1)
6
Low (1)
10
Low (1)
Port Talbot Prince Street 2
Updated: 27/04/2025 09:00
Not measured Not measured Not measured 7
Low (1)
10
Low (1)
Rhondda Glyncoch Garth Avenue
Updated: 27/04/2025 10:00
Not measured Not measured Not measured 7
Low (1)
9
Low (1)
Rhondda Mountain Ash
Updated: 27/04/2025 05:00
Not measured 15
Low (1)
Not measured Not measured Not measured
Rhondda Pontypridd Gelliwastad Rd
Updated: 27/04/2025 06:00
Not measured 8
Low (1)
Not measured Not measured Not measured
Rhondda-Cynon-Taf Broadway
Updated: 26/04/2025 19:00
Not measured No data Not measured Not measured Not measured
Rhondda-Cynon-Taf Pontypridd A470
Updated: 27/04/2025 10:00
Not measured 6
Low (1)
Not measured Not measured Not measured
Swansea Cwm Level Park
Updated: 24/01/2025 13:00
No data No data Not measured Not measured Not measured
Swansea Hafod DOAS
Updated: 25/01/2025 18:00
No data No data Not measured Not measured Not measured
Swansea Morfa Road NOX
Updated: 23/01/2025 20:00
Not measured No data Not measured Not measured Not measured
Swansea Morriston Roadside
Updated: 14/11/2024 15:00
No data No data Not measured No data Not measured
Swansea Port Tennant Roadside
Updated: 31/01/2025 12:00
Not measured No data Not measured No data Not measured
Swansea Roadside
Updated: 27/04/2025 10:00
Not measured 10
Low (1)
Not measured 8
Low (1)
14
Low (1)
Swansea St Thomas DOAS
Updated: 25/01/2025 18:00
No data No data No data Not measured Not measured
Swansea Station Court High Street
Updated: 31/01/2025 13:00
Not measured No data Not measured Not measured Not measured
Wrexham
Updated: 27/04/2025 10:00
Not measured 16
Low (1)
2
Low (1)
9
Low (1)
12
Low (1)
Wrexham A483
Updated: 27/04/2025 10:00
Not measured 15
Low (1)
Not measured Not measured Not measured
Wrexham Chirk
Updated: 27/04/2025 10:00
Not measured 11
Low (1)
Not measured No data No data
Wrexham Chirk Community Hospital
Updated: 27/04/2025 10:00
Not measured 12
Low (1)
Not measured 2
Low (1)
5
Low (1)