Current measured levels are shown in the table below - showing concentrations and, where applicable, the corresponding index and bands.
Current Levels
| 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: 24/10/2025 06:00 |
Not measured | 6 Low (1) |
Not measured | Not measured | Not measured |
| Aston Hill Updated: 24/10/2025 06:00 |
65 Low (2) |
1 Low (1) |
Not measured | Not measured | Not measured |
| Caerphilly Islwyn Road Wattsville Updated: 24/10/2025 05:00 |
Not measured | 9 Low (1) |
Not measured | Not measured | Not measured |
| Caerphilly White Street Updated: 24/10/2025 05:00 |
Not measured | 3 Low (1) |
Not measured | Not measured | 6 Low (1) |
| Cardiff Castle Street Updated: 24/10/2025 06:00 |
Not measured | 36 Low (1) |
Not measured | 6 Low (1) |
13 Low (1) |
| Cardiff Centre Updated: 24/10/2025 06:00 |
48 Low (2) |
15 Low (1) |
1 Low (1) |
8 Low (1) |
11 Low (1) |
| Cardiff Newport Road Updated: 24/10/2025 06:00 |
Not measured | 35 Low (1) |
Not measured | Not measured | 9 Low (1) |
| Chepstow A48 Updated: 24/10/2025 06:00 |
Not measured | 69 Low (2) |
Not measured | 7 Low (1) |
10 Low (1) |
| Cimla Road / Victoria Gardens Updated: 28/06/2024 09:00 |
Not measured | No data | Not measured | Not measured | Not measured |
| Cwmbran Crownbridge Updated: 24/10/2025 06:00 |
66 Low (2) |
2 Low (1) |
Not measured | Not measured | 11 Low (1) |
| Hafod-yr-ynys Hill Roadside Updated: 24/10/2025 05:00 |
Not measured | 30 Low (1) |
Not measured | Not measured | Not measured |
| Marchlyn Mawr Updated: 24/10/2025 06:00 |
61 Low (2) |
0 Low (1) |
Not measured | Not measured | Not measured |
| Nantgarw Road Updated: 24/10/2025 05:00 |
Not measured | 15 Low (1) |
Not measured | Not measured | Not measured |
| Narberth Updated: 23/10/2025 18:00 |
No data | No data | No data | No data | No data |
| Newport M4 Junction 25 Updated: 24/10/2025 07:00 |
29 Low (1) |
59 Low (1) |
Not measured | Not measured | Not measured |
| Newport M4 Junction 25 West Updated: 24/10/2025 06:00 |
Not measured | 7 Low (1) |
Not measured | Not measured | Not measured |
| Newport St Julians Comp School Updated: 24/10/2025 06:00 |
Not measured | 16 Low (1) |
Not measured | 3 Low (1) |
6 Low (1) |
| Port Talbot Dyffryn School Updated: 24/10/2025 06:00 |
Not measured | Not measured | Not measured | 5 Low (1) |
11 Low (1) |
| Port Talbot Little Warren Updated: 24/10/2025 06:00 |
Not measured | Not measured | Not measured | 5 Low (1) |
14 Low (1) |
| Port Talbot M4 Junction 41 Updated: 24/10/2025 06:00 |
Not measured | 26 Low (1) |
Not measured | Not measured | Not measured |
| Port Talbot Margam Updated: 24/10/2025 06:00 |
55 Low (2) |
22 Low (1) |
1 Low (1) |
4 Low (1) |
9 Low (1) |
| Port Talbot Prince Street 2 Updated: 24/10/2025 05:00 |
Not measured | Not measured | Not measured | 6 Low (1) |
8 Low (1) |
| Rhondda Glyncoch Garth Avenue Updated: 24/10/2025 07:00 |
Not measured | Not measured | Not measured | 3 Low (1) |
6 Low (1) |
| Rhondda Mountain Ash Updated: 24/10/2025 07:00 |
Not measured | 17 Low (1) |
Not measured | Not measured | Not measured |
| Rhondda Pontypridd Gelliwastad Rd Updated: 23/10/2025 20:00 |
Not measured | 27 Low (1) |
Not measured | Not measured | Not measured |
| Rhondda-Cynon-Taf Broadway Updated: 24/10/2025 06:00 |
Not measured | 29 Low (1) |
Not measured | Not measured | Not measured |
| Rhondda-Cynon-Taf Pontypridd A470 Updated: 24/10/2025 06:00 |
Not measured | 5 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: 24/10/2025 06:00 |
Not measured | 41 Low (1) |
Not measured | 3 Low (1) |
8 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: 24/10/2025 06:00 |
Not measured | 2 Low (1) |
No data | 3 Low (1) |
6 Low (1) |
| Wrexham A483 Updated: 24/10/2025 05:00 |
Not measured | 7 Low (1) |
Not measured | Not measured | Not measured |
| Wrexham Chirk Updated: 24/10/2025 06:00 |
Not measured | 46 Low (1) |
Not measured | 7 Low (1) |
19 Low (2) |
| Wrexham Chirk Community Hospital Updated: 24/10/2025 06:00 |
Not measured | 15 Low (1) |
Not measured | 1 Low (1) |
2 Low (1) |