Is the Air Really Cleaner on Rainy Days?
You’ve probably heard people say the air is fresher when it rains. That’s true—but only partly.
When it rains, the falling water washes dust and suspended particles out of the air. For a short time, PM2.5 levels drop, the air feels cooler, and breathing seems easier. But this “washing away” effect is only temporary, because the sources of pollution don’t actually disappear.
The Pollution Never Really Stops
Even in the rain, traffic keeps moving, and cars and motorcycles continue to release exhaust fumes. Factories keep operating and emitting pollutants. Once the rain eases or stops, and the ground begins to dry, the dust and dirt pressed down by the rain can easily be stirred back into the air.
Then there are the pollution sources we often overlook—such as kitchen exhaust from restaurants and food stalls. Rain doesn’t stop the cooking, and the smoke still flows outside. In fact, the humid air on rainy days can make these odors linger longer, spreading through streets and neighborhoods.
So yes, rain can temporarily reduce the dust floating in the air, but it doesn’t make pollution “disappear.” Protecting your respiratory health means paying attention to air quality every day—not just relying on the weather.
Rain Brings Another Challenge: Humidity
Besides pollution, the biggest annoyance on rainy days is dampness. Outdoors is wet, and indoors quickly follows. Common problems include:
Clothes that won’t dry and start to smell sour
Mold spots on walls or inside closets
Stuffy, humid air that feels uncomfortable to breathe
High indoor humidity doesn’t just feel sticky—it also encourages the growth of dust mites and mold spores, which is especially bad news for people with allergies or asthma.
Dehumidify for Comfort and Health
Here’s a tip: on rainy days, always use a dehumidifier. You don’t have to run it all day if you’re short on time or want to save energy—but make sure it runs long enough to lower the overall indoor humidity. Simply evaporating moisture from walls or clothes into the air can make the space feel even more damp.
You can also do short, controlled ventilation to keep fresh air moving through the house, helping reduce odors and that heavy, humid feeling.
Give Your Family the Best Air Possible
Rainy days might be soggy outside, but at home you can keep the air dry, clean, and comfortable.
Caring for your air quality means caring for your family’s health.
Breathe well, live well—every single day.
Q: How can indoor spaces be both dehumidified and kept clean from airborne particles?
A: Using a dehumidifier together with Dacian’s Dust Window Filter provides an effective solution. Our Dust Window Filter is a PM2.5 window screen capable of blocking up to 99% of suspended particles as small as 0.075 microns. It meets HEPA 13 filtration standards, is translucent yet practically invisible, and is both waterproof and breathable—helping maintain clean, fresh air while controlling indoor humidity.