Indoor Air Quality

Air Quality in Your Home

The air you breathe inside your home can become polluted from sources that come from both inside and outside.

We spend about 90% of our time indoors. Indoor air pollution can be as high as, and sometimes higher than, outdoor levels. The quality of the air you breathe can affect your health.

Indoor air pollutant examples	Outdoor air pollutant examples
Carbon monoxide from improperly vented or improperly working heaters, gas stoves and dryers Off-gassing volatile organic compounds (VOCs) from glues, paints and varnishes Wood smoke from burning wood indoors Secondhand smoke Mold Chemicals in household cleaning products, personal care products and pesticides Pet dander and dust mites Hobbies like 3D printing, welding or woodworking	Idling cars near windows or in an attached garage Backyard trash burning Wildfire smoke Radon Pollen Dust from roadways, agriculture and construction Industrial and commercial sources like manufacturing, dry cleaners and gas stations

Health effects of breathing polluted indoor air

Breathing air pollutants can lead to health effects. The health effects you may experience depend on the amount you breathe in, the length of time you are exposed, as well as your family history, age and general health. Some people are especially sensitive to air pollutants, including babies, young children, older adults, and people with breathing problems.

Air pollution can make it harder to breathe if you have asthma or other respiratory diseases. It can also trigger allergic reactions and may make it more likely for you to have a heart attack or stroke. Some pollutants, like carbon monoxide, can cause headaches, nausea, vomiting, brain damage and even death. Others, like radon, can increase your risk of getting cancer.

Improve your indoor air quality

Using source control, ventilation and filtration can help reduce your exposure to indoor pollutants and improve indoor air quality. See the video and sections below for tips.

Source control

Removing or reducing sources of pollution – called source control – is the best way to improve indoor air quality. Examples of source control include:

Swapping toxic cleaners for safer cleaners like soap and water.
Using integrated pest management to monitor and control pests instead of using pesticide sprays and foggers.
Testing for radon and fixing a radon problem if found.
Decluttering and damp dusting to reduce asthma triggers, allergens, pests and pollutants.
Keeping windows closed when outdoor air quality is poor.
Avoiding smoking or using e-cigarettes indoors.
Having your combustion appliances inspected annually to make sure they are working properly.

Ventilation

Bringing in fresh, outdoor air helps dilute indoor air pollutants. There are two types of ventilation:

Natural ventilation, which includes opening windows and doors. Avoid doing this if the air quality outdoors is unhealthy because of wildfire smoke or other pollution.
Mechanical ventilation, which includes bathroom and kitchen exhaust fans and may include your home’s heating, ventilation and air conditioning (HVAC) system.

Filtration

Using air filters helps remove particles from the air. There are two ways to filter your home’s air:

Using and maintaining filters as part of your home’s heating, ventilation and air conditioning (HVAC) system.
Using a portable air cleaner, also known as an air purifier.

Learn more about filters and portable air cleaners in EPA’s Guide to Air Cleaners in the Home