Indoor pollution can make you sick. Here's how to keep your home's air clean

This summer, with wildfire smoke suffocating swaths of North America, we've been warned to stay indoors to avoid poor-quality air. But there are things inside your home you don't necessarily want to be inhaling either.

Once you start learning about possible indoor air pollutants, it may be difficult to stop noticing them, warns Katherine Pruitt, national senior director for policy at the American Lung Association.

One source is moisture stemming from flooding, leaks, or even just high humidity, which can "support the proliferation of germs, pathogens, mold, dust mites, allergens or actual toxins," says Pruitt.

Certain gases can be dangerous too. There's carbon monoxide that emanates from combustion appliances, like gas stoves or space heaters. And there's radon, which is a radioactive gas that "comes into the home naturally," Pruitt says, "and which can result in lung cancer."

You also have to look out for consumer goods and cleaning supplies that can release pollutants like formaldehyde, benzene and other volatile organic compounds. These can be found in furnishings like wall covers, furniture and carpets.

And, of course, smoking or burning a fire