SmogRank / United Kingdom / Wales

Air quality in Cwmafan

Wales, United Kingdom. Over the last 24 hours its air rated Good, the 470th most polluted of 738 cities measured.

24-hour average22US AQI
Good

PM2.5 4.0 µg/m³, 0.3× the WHO 24-hour guideline. The figure the 24-hour ranking uses.

Latest hour: 22 US AQI (4.0 µg/m³), local time

About usual for early October (4.3 µg/m³).

Last 4 days, hour by hour

15307 Oct 17:00 local, 2026-10-07 16:00 UTC: 2.0 µg/m³7 Oct 18:00 local, 2026-10-07 17:00 UTC: 0.0 µg/m³7 Oct 19:00 local, 2026-10-07 18:00 UTC: 3.0 µg/m³7 Oct 20:00 local, 2026-10-07 19:00 UTC: 7.0 µg/m³7 Oct 21:00 local, 2026-10-07 20:00 UTC: 7.0 µg/m³7 Oct 22:00 local, 2026-10-07 21:00 UTC: 4.0 µg/m³7 Oct 23:00 local, 2026-10-07 22:00 UTC: 0.0 µg/m³8 Oct 00:00 local, 2026-10-07 23:00 UTC: 4.0 µg/m³8 Oct 01:00 local, 2026-10-08 00:00 UTC: 5.0 µg/m³8 Oct 02:00 local, 2026-10-08 01:00 UTC: 3.0 µg/m³8 Oct 03:00 local, 2026-10-08 02:00 UTC: 5.0 µg/m³8 Oct 04:00 local, 2026-10-08 03:00 UTC: 2.0 µg/m³8 Oct 05:00 local, 2026-10-08 04:00 UTC: 0.0 µg/m³8 Oct 06:00 local, 2026-10-08 05:00 UTC: 1.0 µg/m³8 Oct 07:00 local, 2026-10-08 06:00 UTC: 4.0 µg/m³8 Oct 08:00 local, 2026-10-08 07:00 UTC: 3.0 µg/m³8 Oct 09:00 local, 2026-10-08 08:00 UTC: 2.0 µg/m³8 Oct 10:00 local, 2026-10-08 09:00 UTC: 6.0 µg/m³8 Oct 11:00 local, 2026-10-08 10:00 UTC: 10.0 µg/m³8 Oct 12:00 local, 2026-10-08 11:00 UTC: 7.0 µg/m³8 Oct 13:00 local, 2026-10-08 12:00 UTC: 8.0 µg/m³8 Oct 14:00 local, 2026-10-08 13:00 UTC: 5.0 µg/m³8 Oct 15:00 local, 2026-10-08 14:00 UTC: 3.0 µg/m³8 Oct 16:00 local, 2026-10-08 15:00 UTC: 3.0 µg/m³8 Oct 17:00 local, 2026-10-08 16:00 UTC: 4.0 µg/m³8 Oct 18:00 local, 2026-10-08 17:00 UTC: 5.0 µg/m³8 Oct 19:00 local, 2026-10-08 18:00 UTC: 4.0 µg/m³Oct 5Oct 6Oct 7Oct 8
Cwmafan's local time; hover a bar for UTC. Dashed line: WHO 24-hour guideline (15 µg/m³).

Where Cwmafan ranks

24 hours#470of 738, at 22 US AQI (4.0 µg/m³)
7 days–not enough data
30 days–not enough data
This year–not enough data

Unhealthy days this year: 0 of 74 measured days had a daily mean over 35.4 µg/m³ (US AQI 101+).

Peak not checked: Cwmafan is measured at one place (monitors within 3 km of each other count as one), and its worst hours need a second place to confirm them.

The last 12 months, day by day

1102031Nov 2025DecJan 2026FebMarAprMayJunJulAugSepOct2025-11-01: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-02: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-03: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-04: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-05: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-06: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-07: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-08: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-09: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-10: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-11: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-12: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-13: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-14: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-15: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-16: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-17: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-18: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-19: 2.7 µg/m³2025-11-20: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-21: 3.6 µg/m³2025-11-22: 3.1 µg/m³2025-11-23: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-24: 3.8 µg/m³2025-11-25: no daily value, under 18 hours of readings, or readings that failed our checks2025-11-26: 3.0 µg/m³2025-11-27: 3.5 µg/m³2025-11-28: 5.7 µg/m³2025-11-29: 3.5 µg/m³2025-11-30: 3.5 µg/m³2025-12-01: 3.5 µg/m³2025-12-02: no daily value, under 18 hours of readings, or readings that failed our checks2025-12-03: 4.1 µg/m³2025-12-04: 4.8 µg/m³2025-12-05: 6.2 µg/m³2025-12-06: 8.0 µg/m³2025-12-07: 5.5 µg/m³2025-12-08: 5.1 µg/m³2025-12-09: 5.0 µg/m³2025-12-10: 8.7 µg/m³2025-12-11: 6.2 µg/m³2025-12-12: 9.9 µg/m³2025-12-13: 7.9 µg/m³2025-12-14: 4.2 µg/m³2025-12-15: 4.3 µg/m³2025-12-16: 3.8 µg/m³2025-12-17: 4.3 µg/m³2025-12-18: 3.7 µg/m³2025-12-19: 4.5 µg/m³2025-12-20: 3.9 µg/m³2025-12-21: 2.8 µg/m³2025-12-22: 2.5 µg/m³2025-12-23: 5.4 µg/m³2025-12-24: 7.3 µg/m³2025-12-25: 4.5 µg/m³2025-12-26: 6.2 µg/m³2025-12-27: 6.4 µg/m³2025-12-28: no daily value, under 18 hours of readings, or readings that failed our checks2025-12-29: no daily value, under 18 hours of readings, or readings that failed our checks2025-12-30: 3.7 µg/m³2025-12-31: 4.8 µg/m³2026-01-01: 6.7 µg/m³2026-01-02: 2.9 µg/m³2026-01-03: 5.0 µg/m³2026-01-04: 3.4 µg/m³2026-01-05: 3.6 µg/m³2026-01-06: 2.9 µg/m³2026-01-07: 3.3 µg/m³2026-01-08: 5.7 µg/m³2026-01-09: 2.6 µg/m³2026-01-10: 4.5 µg/m³2026-01-11: 4.3 µg/m³2026-01-12: 7.8 µg/m³2026-01-13: 5.6 µg/m³2026-01-14: 4.5 µg/m³2026-01-15: 4.4 µg/m³2026-01-16: 4.8 µg/m³2026-01-17: 2.0 µg/m³2026-01-18: 4.9 µg/m³2026-01-19: 8.4 µg/m³2026-01-20: 4.1 µg/m³2026-01-21: 2.0 µg/m³2026-01-22: 3.3 µg/m³2026-01-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-01-24: 2.8 µg/m³2026-01-25: 3.6 µg/m³2026-01-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-01-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-01-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-01-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-01-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-01-31: no daily value, under 18 hours of readings, or readings that failed our checks2026-02-01: 3.3 µg/m³2026-02-02: 2.1 µg/m³2026-02-03: 4.0 µg/m³2026-02-04: 6.5 µg/m³2026-02-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-02-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-02-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-02-08: 2.6 µg/m³2026-02-09: 3.5 µg/m³2026-02-10: 2.6 µg/m³2026-02-11: 4.7 µg/m³2026-02-12: 7.1 µg/m³2026-02-13: 4.3 µg/m³2026-02-14: 2.0 µg/m³2026-02-15: 2.1 µg/m³2026-02-16: 4.1 µg/m³2026-02-17: 4.5 µg/m³2026-02-18: 3.9 µg/m³2026-02-19: 2.4 µg/m³2026-02-20: 7.4 µg/m³2026-02-21: 8.0 µg/m³2026-02-22: 4.2 µg/m³2026-02-23: 8.1 µg/m³2026-02-24: 6.6 µg/m³2026-02-25: 6.4 µg/m³2026-02-26: 5.8 µg/m³2026-02-27: 2.6 µg/m³2026-02-28: 2.5 µg/m³2026-03-01: 2.8 µg/m³2026-03-02: 4.9 µg/m³2026-03-03: 4.3 µg/m³2026-03-04: 9.6 µg/m³2026-03-05: 14.7 µg/m³2026-03-06: 6.8 µg/m³2026-03-07: 4.5 µg/m³2026-03-08: 13.5 µg/m³2026-03-09: 20.0 µg/m³2026-03-10: 5.0 µg/m³2026-03-11: 5.2 µg/m³2026-03-12: 6.4 µg/m³2026-03-13: 5.3 µg/m³2026-03-14: 4.2 µg/m³2026-03-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-03-16: 6.4 µg/m³2026-03-17: 6.8 µg/m³2026-03-18: 7.8 µg/m³2026-03-19: 7.3 µg/m³2026-03-20: 15.9 µg/m³2026-03-21: 18.1 µg/m³2026-03-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-03-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-03-24: 7.6 µg/m³2026-03-25: 3.9 µg/m³2026-03-26: 5.4 µg/m³2026-03-27: 3.7 µg/m³2026-03-28: 5.2 µg/m³2026-03-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-03-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-03-31: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-08: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-09: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-10: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-11: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-12: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-13: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-14: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-16: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-17: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-18: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-19: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-20: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-21: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-24: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-25: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-04-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-08: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-09: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-10: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-11: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-12: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-13: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-14: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-16: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-17: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-18: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-19: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-20: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-21: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-24: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-25: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-05-31: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-08: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-09: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-10: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-11: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-12: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-13: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-14: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-16: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-17: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-18: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-19: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-20: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-21: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-24: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-25: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-06-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-08: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-09: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-10: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-11: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-12: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-13: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-14: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-16: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-17: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-18: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-19: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-20: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-21: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-24: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-25: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-07-31: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-08: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-09: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-10: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-11: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-12: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-13: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-14: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-16: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-17: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-18: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-19: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-20: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-21: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-24: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-25: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-08-31: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-05: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-06: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-07: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-08: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-09: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-10: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-11: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-12: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-13: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-14: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-15: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-16: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-17: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-18: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-19: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-20: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-21: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-22: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-23: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-24: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-25: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-26: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-27: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-28: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-29: no daily value, under 18 hours of readings, or readings that failed our checks2026-09-30: no daily value, under 18 hours of readings, or readings that failed our checks2026-10-01: no daily value, under 18 hours of readings, or readings that failed our checks2026-10-02: no daily value, under 18 hours of readings, or readings that failed our checks2026-10-03: no daily value, under 18 hours of readings, or readings that failed our checks2026-10-04: no daily value, under 18 hours of readings, or readings that failed our checks2026-10-05: no daily value, no readings from the monitor2026-10-06: no daily value, no readings from the monitor2026-10-07: no daily value, only 7 of the 18 hours a day needs
3 of 127 measured days were over the WHO 24-hour guideline (15 µg/m³). 238 days without a value: 2 with no readings from the monitor, 1 with readings for part of the day (a day needs 18 hours), 235 with under 18 hours of readings or readings that failed our checks; point at a grey square for its reason (why days go blank). One row per month, one square per local day.
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Where it stood each day

Top 10Top 100#1#10#100#1,000#3,154NovDecJanFebMar#2,281
Its rank on each day's world board, #1 being the most polluted city that day. Higher is worse. Each gridline down is ten times the rank above it (#1, #10, #100, #1,000), so the top places get the most room. See it among every city.

2026 against 2025, month by month

15Jan 2026: 4.3 µg/m³JanFeb 2026: 4.5 µg/m³FebMar 2026: 7.8 µg/m³MarApr 2025: 7.5 µg/m³AprMay 2025: 6.7 µg/m³MayJun 2025: 5.6 µg/m³JunJul 2025: 5.6 µg/m³JulAug 2025: 5.3 µg/m³AugSep 2025: 3.2 µg/m³SepOct 2025: 4.4 µg/m³OctNovDec 2025: 5.3 µg/m³Dec
Faded bars: 2025. A month shows once it has 10 measured days.

Monitors

1 listed: 1 reference, 0 low-cost

PM2.5 from 1 reference monitor, updated hourly.

StationOperatorType
Port Talbot MargamOGL v3 (© Crown copyright Defra via uk-air.defra.gov.uk)DefraReference

The city's value is the median of its reference monitors each hour, when at least a third of them report (three are always enough); low-cost sensors are listed but not counted when reference monitors exist. Data via OpenAQ; licences as listed. How we rank. Embed this on your site.

Use this page

SmogRank, PM2.5 daily means, Cwmafan, United Kingdom, 8 Oct 2025 – 28 Mar 2026, smogrank.com/gb/cwmafan (accessed 8 Oct 2026).

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You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.

Compare Cwmafan with another city

Side by side with Swansea (the nearest), London (United Kingdom's worst on 30 days), Gujranwala (the world's worst on 30 days).

Other cities in United Kingdom

30-day averages, US AQI. All of United Kingdom.

Updated 2026-10-08 20:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the US AQI PM2.5 sub-index. Some readings: Uzhydromet (Uzbekistan's Hydrometeorological Service); Department of Environment, Nepal; Vietnam's government monitors; Aurassure; Umhverfisstofnun (Environment Agency of Iceland); Love My Air (City and County of Denver), no reuse terms published (why we use them).