Performance of AirGradient OpenAir in humid climate

Rafid · February 20, 2026, 9:17am

Hello everyone,

I would like to know about your experience with AirGradient’s outdoor sensors in humid conditions (relative humidity consistently above 80%). Do the particle counts remain stable, or do they go way higher than the reference stations nearby? Please let me know specially if you are in tropical regions such as South and South-East Asia.

I do not currently own an AirGradient sensor, but I am considering one. I have an IQAir AirVisual Outdoor, stationed in Khulna, Bangladesh. I noticed the PM2.5 counts go up in the middle of the monsoon when the humidity level crosses 80%, sometimes it even crosses 95%. Here in Bangladesh, the wind remains quite humid in the winter season. Also, winter is the peak pollution season in Khulna as the transboundary pollution from neighboring Indo-Gangetic plains overwhelms the air in my city. In this period, the AQI remains in the range of 200-300. Then comes the fog-belt, in that period the humidity remains above 80% all-day and AQI remains above 300 as well.

I know that the laser particle sensors have issues with humidity, But I want to know how much their performance is impacted by humidity in practical outdoor condition.

Ethan_AirGradient · February 23, 2026, 1:35am

Hi @Rafid,

We have a lot of monitors deployed in South Asia and Southeast Asia as we’re based in Thailand. Even right now, my outdoor monitor is reporting 87% relative humidity! The particle counts generally remain stable, and the EPA correction can be used to further account for the impact of humidity on the particles.

If you would like compare readings from references and our monitors, I would recommend checking out our air quality map! Any square with a white outline is a reference (like those pointed out below), and if you click on a square without a white border you can see if it’s an AirGradient monitor:

If there is a nearby city (or a city with similar conditions) that has a reference with public data and an AirGradient monitor, you should be able to compare these here. Hopefully it gives a bit more insight as to how the sensors normally read relative to a reference.