Is the air quality good in Johannesburg?
As of May 31, 2026, at 9:30 AM (local time, GMT+2), air quality in Johannesburg, South Africa, is poor, with the AQI at 170, classified as "unhealthy," with PM2.5 as the dominant pollutant.
Johannesburg ranks as the most polluted major city in the world at this hour. These conditions pose serious health risks, particularly for children, the elderly, and those with respiratory or cardiovascular conditions.
The annual average PM2.5 concentration in Johannesburg for 2025 was 17.1 µg/m³, corresponding to an AQI of 66, classified as "moderate" and 3.42 times higher than the WHO annual guideline of 5 µg/m³.
Today's readings are significantly above that annual average, reflecting an acute winter pollution episode.
For a complete, real-time view of current pollution levels, see Johannesburg's air quality map.
Johannesburg, South Africa, ranked among the most polluted major cities globally, on May 31, 2026, at 9:30 AM (local time). Source: IQAir.
Air quality map of Johannesburg, South Africa, on May 31, 2026, at 9:30 AM (local time). Source: IQAir.
When will the air quality improve in Johannesburg?
The southern hemisphere winter, running from June through August, typically sees much higher pollution levels than the rest of the year, as weather conditions in winter are far more prone to smog formation with less sunlight, less vertical mixing, and pollutants accumulating near the ground.
Meaningful relief is unlikely until spring brings warmer temperatures, stronger winds, and improved atmospheric mixing from September onwards (1).
Hourly air quality forecast for Johannesburg, South Africa, on May 31, 2026, at 9:30 AM (local time). Source: IQAir.
What is causing poor air quality in Johannesburg?
Johannesburg's unique topography on the Highveld escarpment, combined with high pressure systems, results in calm conditions with minimal wind, causing air pollution to become trapped over the city.
The Johannesburg-Pretoria urban area sits in close proximity to the most industrialized region of South Africa, where coal mining, coal-fired power stations, and energy-intensive petrochemical, chemical, and steel industries generate significant pollutant loads (2).
In winter, emissions increase as people burn wood and coal for cooking and heating, there are more grass and veld fires, and conditions are dry and dusty, causing air to recirculate over the region and accumulate pollution.
The main sources are coal-fired power stations, industries, vehicles, prescribed burning, solid fuels for cooking and heating, and waste burning. High PM2.5 levels correlate with elevated SO2 and NO2, indicating that coal and fossil fuel combustion from power plants and industry, rather than open fires alone, are the primary drivers of the most severe pollution episodes (3).
How can I protect myself from poor air quality?
- Get a free air quality app for real-time air quality alerts and forecasts.
- Shut doors and windows and set the HVAC to recirculate mode.
- Contribute to your community’s outdoor air quality data.
- Stay indoors when air quality is poor; if you do need to go outdoors, wear a KN95/FFP2 mask.
- Run a high-performance air purifier to filter particles, gases, and other pollutants.
