Air quality
Air quality in Heshan today
Updated
Unhealthy for Sensitive Groups (US AQI 125) People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors. Model estimate for Mon, Oct 26, 2:00 am (18:00 UTC).
Live AQI, PM2.5, PM10 and ozone for Heshan, Hunan, China, with a 48-hour forecast and the best time to be outside.
- US AQI now
- 125 Unhealthy for Sensitive Groups
- PM2.5
- 43 µg/m³ 2.9× WHO 24-h guideline
- PM10
- 45 µg/m³
- Ozone
- 53 µg/m³
- Dominant pollutant
- PM2.5 sub-index 125
- Best hour today
- 9:00 pm AQI 102
- European AQI
- 56
Air quality in Heshan right now
Right now the modelled US Air Quality Index for Heshan, Hunan, China is 125, which falls in the "Unhealthy for Sensitive Groups" band (up to 150). People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors.
The index is driven mainly by PM2.5, whose own sub-index is 125. Fine and coarse particles come from traffic, heating, industry, dust and smoke; they build up on calm nights and clear when wind or rain arrives.
PM2.5 is 43 µg/m³, 2.9 times the WHO 24-hour guideline of 15 µg/m³; PM10 is 45 µg/m³ against a guideline of 45; ozone is 53 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 12 µg/m³ (below the 24-hour guideline of 25).
Also this hour: carbon monoxide 542 µg/m³.
Heshan AQI forecast: next 48 hours
Over the next 24 hours the AQI is forecast to range from 93 around Tue 2:00 am to 125 around Mon 2:00 am, from "Moderate" at best to "Unhealthy for Sensitive Groups" at worst.
The following day is expected to be cleaner, averaging about 103 against 113 for the next 24 hours.
| Local time (Asia/Shanghai) | US AQI | Category | PM2.5 µg/m³ | PM10 µg/m³ | Ozone µg/m³ |
|---|---|---|---|---|---|
| Mon 2:00 am | 125 | Unhealthy for Sensitive Groups | 43.2 | 45 | 53 |
| Mon 5:00 am | 123 | Unhealthy for Sensitive Groups | 42.7 | 44 | 41 |
| Mon 8:00 am | 121 | Unhealthy for Sensitive Groups | 46 | 47 | 33 |
| Mon 11:00 am | 119 | Unhealthy for Sensitive Groups | 40.7 | 42 | 98 |
| Mon 2:00 pm | 116 | Unhealthy for Sensitive Groups | 21.9 | 23 | 136 |
| Mon 5:00 pm | 111 | Unhealthy for Sensitive Groups | 19.7 | 20 | 124 |
| Mon 8:00 pm | 105 | Unhealthy for Sensitive Groups | 20.8 | 21 | 96 |
| Mon 11:00 pm | 97 | Moderate | 25.7 | 26 | 64 |
| Tue 2:00 am | 93 | Moderate | 33.8 | 34 | 45 |
| Tue 5:00 am | 91 | Moderate | 42.8 | 44 | 39 |
| Tue 8:00 am | 92 | Moderate | 54.9 | 56 | 34 |
| Tue 11:00 am | 95 | Moderate | 53.1 | 54 | 47 |
| Tue 2:00 pm | 99 | Moderate | 47.3 | 49 | 69 |
| Tue 5:00 pm | 108 | Unhealthy for Sensitive Groups | 45.5 | 47 | 69 |
| Tue 8:00 pm | 115 | Unhealthy for Sensitive Groups | 43.8 | 45 | 52 |
| Tue 11:00 pm | 122 | Unhealthy for Sensitive Groups | 48 | 50 | 41 |
| Wed 2:00 am | 129 | Unhealthy for Sensitive Groups | 50.8 | 53 | 34 |
Every third hour of the CAMS forecast via Open-Meteo. US AQI uses rolling averages (24 h for particles, 8 h for ozone), so it moves more slowly than the hourly concentrations.
Best time to be outside in Heshan today
Between 6 am and 9 pm local time, the cleanest air today is forecast around 9:00 pm (AQI 102, Unhealthy for Sensitive Groups) and the worst around 6:00 am (AQI 122). That is a swing of 20 points, so a run or walk around 9:00 pm is noticeably better.
Heshan vs the rest of China
Across 467 China cities we track, the average US AQI right now is 84 (Moderate). Heshan at 125 is 41 points worse than average.
It ranks 408 of 467 from cleanest to most polluted; the cleanest is Hulunbuir (21) and the most polluted Artux (264).
For context, the median across 3,909 cities worldwide is 57.
Air quality in cities near Heshan
| City | Distance | US AQI | Category | PM2.5 µg/m³ |
|---|---|---|---|---|
| Changsha | 74 km | 128 | Unhealthy for Sensitive Groups | 47.5 |
| Changde | 82 km | 128 | Unhealthy for Sensitive Groups | 42.5 |
| Xiangtan | 97 km | 128 | Unhealthy for Sensitive Groups | 47.5 |
| Loudi | 99 km | 133 | Unhealthy for Sensitive Groups | 57 |
| Zhuzhou | 114 km | 118 | Unhealthy for Sensitive Groups | 63.6 |
| Yueyang | 115 km | 111 | Unhealthy for Sensitive Groups | 43.4 |
| Guankou | 133 km | 92 | Moderate | 40.5 |
| Shaoyang | 172 km | 138 | Unhealthy for Sensitive Groups | 67.3 |
Model vs measured
We found no measured PM2.5 sensor cell within 25 km of Heshan, so the numbers on this page are model estimates. Models capture regional pollution well but can miss very local sources such as a busy road or a nearby fire.
Wildfire smoke
PM2.5 is forecast to reach 46 µg/m³ in the next 24 hours while NASA satellites detected 22 fire hotspots within 300 km in the last day (nearest about 78 km away). Smoke is a likely contributor: keep windows closed, run an air purifier or HVAC filter, and check the fire map before heading out.
Advice for sensitive groups
At 125, children, older adults, pregnant people and anyone with asthma, COPD or heart disease should limit time outdoors, especially strenuous activity. A well-fitted N95/FFP2 mask cuts particle exposure; it does not filter ozone.
What the US AQI numbers mean
| US AQI | Category | What it means |
|---|---|---|
| 0-50 | Good | Air quality is satisfactory and poses little or no risk; a good time for outdoor activity. |
| 51-100 | Moderate | Acceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors. |
| 101-150 | Unhealthy for Sensitive Groups | People with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors. |
| 151-200 | Unhealthy | Everyone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed. |
| 201-300 | Very Unhealthy | Health alert: everyone should avoid prolonged or heavy exertion outdoors, and sensitive groups should stay indoors. |
| 301-500 | Hazardous | Emergency conditions: everyone should avoid all outdoor physical activity and stay indoors with filtered air if possible. The scale tops out at 500; heavier dust or smoke is shown as 500. |
Values on this page are modelled by CAMS (Copernicus) and served by Open-Meteo; they are estimates for the area around the city centre, not readings from an official monitor.
Nearby cities
More for Heshan
Air quality elsewhere
Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), NASA FIRMS.