Air quality

Air quality in Hai Bà Trưng today

Updated

Unhealthy for Sensitive Groups (US AQI 112) 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, 3:00 am (20:00 UTC).

Live AQI, PM2.5, PM10 and ozone for Hai Bà Trưng, Hanoi, Vietnam, with a 48-hour forecast and the best time to be outside.

US AQI now
112 Unhealthy for Sensitive Groups
PM2.5
69 µg/m³ 4.6× WHO 24-h guideline
PM10
71 µg/m³
Ozone
58 µg/m³
Dominant pollutant
PM2.5 sub-index 112
Best hour today
2:00 pm AQI 113
European AQI
69

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Air quality in Hai Bà Trưng right now

Right now the modelled US Air Quality Index for Hai Bà Trưng, Hanoi, Vietnam is 112, 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 112. 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 69 µg/m³, 4.6 times the WHO 24-hour guideline of 15 µg/m³; PM10 is 71 µg/m³ against a guideline of 45; ozone is 58 µg/m³ (below the WHO 8-hour level of 100); nitrogen dioxide is 32 µg/m³ (above the 24-hour guideline of 25).

Also this hour: carbon monoxide 773 µg/m³.

Hai Bà Trưng AQI forecast: next 48 hours

Over the next 24 hours the AQI is forecast to range from 112 around Mon 3:00 am to 176 around Mon 6:00 pm, from "Unhealthy for Sensitive Groups" at best to "Unhealthy" at worst.

The following day is expected to be worse, averaging about 156 against 131 for the next 24 hours.

Local time (Asia/Bangkok)US AQICategoryPM2.5 µg/m³PM10 µg/m³Ozone µg/m³
Mon 3:00 am112Unhealthy for Sensitive Groups68.77158
Mon 6:00 am118Unhealthy for Sensitive Groups434570
Mon 9:00 am116Unhealthy for Sensitive Groups26.130136
Mon 12:00 pm115Unhealthy for Sensitive Groups25.226195
Mon 3:00 pm137Unhealthy for Sensitive Groups3536199
Mon 6:00 pm176Unhealthy41.642133
Mon 9:00 pm138Unhealthy for Sensitive Groups60.16161
Tue 12:00 am126Unhealthy for Sensitive Groups107.110827
Tue 3:00 am141Unhealthy for Sensitive Groups99.210028
Tue 6:00 am150Unhealthy for Sensitive Groups87.38826
Tue 9:00 am154Unhealthy4343133
Tue 12:00 pm155Unhealthy29.130201
Tue 3:00 pm155Unhealthy26.427195
Tue 6:00 pm176Unhealthy50.351108
Tue 9:00 pm156Unhealthy69.47047
Wed 12:00 am156Unhealthy103.110531
Wed 3:00 am156Unhealthy106.210721

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 Hai Bà Trưng today

Between 6 am and 9 pm local time, the cleanest air today is forecast around 2:00 pm (AQI 113, Unhealthy for Sensitive Groups) and the worst around 6:00 pm (AQI 176). That is a swing of 63 points, so a run or walk around 2:00 pm is noticeably better.

Hai Bà Trưng vs the rest of Vietnam

Across 68 Vietnam cities we track, the average US AQI right now is 83 (Moderate). Hai Bà Trưng at 112 is 29 points worse than average.

It ranks 57 of 68 from cleanest to most polluted; the cleanest is Phu Quoc (38) and the most polluted Hạ Long (113).

For context, the median across 3,909 cities worldwide is 56.

Air quality in cities near Hai Bà Trưng

CityDistanceUS AQICategoryPM2.5 µg/m³
Hanoi1 km112Unhealthy for Sensitive Groups68.7
Hoàn Kiếm2 km112Unhealthy for Sensitive Groups68.7
Đống Đa2 km112Unhealthy for Sensitive Groups68.7
Tương Mai3 km112Unhealthy for Sensitive Groups68.7
Ba Dinh3 km112Unhealthy for Sensitive Groups68.7
Cầu Giấy5 km112Unhealthy for Sensitive Groups68.7
Thanh Xuân5 km112Unhealthy for Sensitive Groups68.7
Long Bien6 km112Unhealthy for Sensitive Groups68.7

Model vs measured

We found no measured PM2.5 sensor cell within 25 km of Hai Bà Trưng, 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 107 µg/m³ in the next 24 hours while NASA satellites detected 136 fire hotspots within 300 km in the last day (nearest about 32 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 112, 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 AQICategoryWhat it means
0-50GoodAir quality is satisfactory and poses little or no risk; a good time for outdoor activity.
51-100ModerateAcceptable for most people. Unusually sensitive people should consider shortening long or heavy exertion outdoors.
101-150Unhealthy for Sensitive GroupsPeople with heart or lung disease, older adults, children and teens should cut back on prolonged or heavy exertion outdoors.
151-200UnhealthyEveryone should reduce prolonged or heavy exertion outdoors; sensitive groups should avoid it and keep windows closed.
201-300Very UnhealthyHealth alert: everyone should avoid prolonged or heavy exertion outdoors, and sensitive groups should stay indoors.
301-500HazardousEmergency 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 Hai Bà Trưng

Air quality elsewhere

Data: Open-Meteo Air Quality API, Copernicus Atmosphere Monitoring Service (CAMS), NASA FIRMS.