When we hear about warnings of “dust” in our homes, we typically assume it’s in reference to the particles we can see accumulating on bookshelves that indicate it may be time for a clean--but this isn’t the full story.

You may have heard of fine dust, or PM2.5, on recent air quality reports and even global health reports. Fine Dust is much different from the traditional dust we see around our homes, and it’s growing presence in our daily lives could pose a serious threat to our health. To help you get the facts straight on fine dust, we’ve created our essential guide about these important particles:

What is Fine Dust?

Fine Dust, specifically known as PM2.5, is particulate matter that can be found in the air that is incredibly small — a single particle has a diameter of less than 2.5 micrometers, which means you can easily fit 40 fine dust particles across the width of a single strand of hair. Fine Dust size renders it practically invisible; it can only be detected with an electron microscope.

Why it’s Important

Although it may be small, fine dust shouldn’t be underestimated — in fact, its size is what makes it more formidable. Unlike larger (and more visible) dust particles, PM2.5 are able to bypass your nose and throat and be absorbed by your lungs and bloodstream, leading to a variety of health effects.

Exposure to Fine Dust can have detrimental health effects, and has been known to lead to coughing, chest tightness, shortness of breath, irritation of the eyes/nose/throat, and can trigger asthma, bronchitis, and other respiratory problems. Scientific studies have also linked exposure to an increased risk for heart attack, stroke, certain cancers, and birth defects.

Fine Dust is especially dangerous for people with heart and lung diseases, older adults, and children, but it has also been proven to affect healthy people.

Sources of Fine Dust

Unfortunately, Fine Dust can be much more common than we realize.

Outdoor air pollution is typically caused by PM2.5. These particles are created from emissions from cars, trucks, buses, power plants, and other activities such as burning fuels from wood and coal. Natural events such as wildfires can also contribute Fine Dust to the air. Fine Dust in outdoor air can easily travel long distances, so activities that create PM2.5 can impact the surrounding area for miles.

A common misconception is that Fine Dust only affects outdoor air quality, but the truth is, PM2.5 can be just as prevalent in your home. Daily activities such as cooking (especially frying, sautéing, and broiling), burning candles, smoking, or using fireplaces or fuel-burning space heaters can add Fine Dust to your home's air.

How can you reduce fine dust in your home?

Since Fine Dust is so small and lightweight, it stays in the air for a much longer time than the larger particles we may be familiar with--making it even easier to inhale. This makes it all the more important to take certain measures to reduce the amount of Fine Dust in your home.

Here are a few tips for keeping your PM2.5 levels low:

Know your outdoor air quality: while it may seem like a good idea to open windows and let in fresh air, do so only if you’re certain that outdoor pollution levels are safe.

Ventilate while cooking: cooking is an incredibly common cause for indoor Fine Dust, so be sure to either run a fan or open a few windows while cooking (especially frying, sautéing, and broiling)

Avoid burning candles: common paraffin candles release fine particles into the air when burned. Opt instead for candles made of beeswax, which produce very little smoke.

Understand your air purifier: if you opt to use an air purifier, make sure it includes a HEPA and activated carbon filters--this will ensure that fine particles are being cleaned from your air.

Know what’s in your air: One of the best ways to keep Fine Dust out of your home is to understand when and how it appears in your air in the first place. Awair tracks PM2.5 and other toxins in your air and gives personalized recommendations to help you create a healthier home environment.