four adults sit in a comfortable living room with plants

Although it may be counterintuitive, indoor air is commonly two to five times more contaminated than outside air. These pollutants are linked to everything from immune system health and chemical sensitivity to cancer. In fact, the EPA ranks indoor air pollution as one of the top five threats to human health. It is essential to understand this issue to find solutions to keep your family healthy.

How Indoor Air Quality Affects Our Health

Because most people spend about 90% of their time inside, promoting indoor air quality is essential. The effects of airborne contaminants can have both immediate and long-term impacts. Common short-term symptoms include a runny nose, fatigue, headaches, and dizziness. Exposure can cause or trigger other conditions such as allergy symptoms, asthma, heart disease, and cancer.

Common Sources of Indoor Air Pollution

Many of the airborne pollutants in our homes originate from what we bring into the house. Furniture, carpeting, cleaning products, building finishes, personal care products, and combustion appliances can all degrade home air quality.

Even biological contaminants such as pet dander, mold, viruses, and dust mites can be troublesome. Outdoor airborne contaminants including pollen and smog can also enter. Because many of the sources of pollution come from within the home, we can make many changes to have healthy home air quality.

How To Improve Air Quality at Home

Use Safe Products

Begin by limiting the use of toxic products and utilizing products as safely as possible. Product labels often provide information on safe use and may advise proper ventilation or only applying a product outdoors.

GREENGUARD-certified products meet stringent third-party criteria for limiting chemical exposure. This program is administered by UL Environment and screens for more than 10,000 chemicals, including formaldehyde and certain volatile organic compound (VOC) levels.

The Carpet and Rug Institute has a Green Label Plus certification for products that help protect indoor air quality, including Mohawk felt rug pads, Safety 1st Heavenly Dreams Blue Crib & Toddler Bed Mattresses, and Flagship Carpets. There are also numerous Environmental Working Group-verified personal care products — including Attitude natural shampoo, conditioner, body cream, and body wash; Big Green Pregnancy Tummy Oil; and Whamisa Organic Flowers Skin Toner — that are free of concerning chemicals.

Inspect Your Home for Air Quality Threats

Storing toxic products can also degrade indoor air quality. Whenever possible, safely dispose of unneeded products and avoid storing them in your home. If you have an attached garage, do not idle vehicles inside of it because this can cause exhaust to enter the house. Inspect and test combustion appliances for leaks and prevent roof and plumbing leaks that can cause mold growth. While you’re at it, get some houseplants known to clean the air such as aloe vera, peace lily, and weeping fig.

Ventilate Your Home

One of the best ways to promote home air quality is through adequate ventilation. This strategy dilutes contaminants, reducing their concentrations. Ventilation also helps prevent moisture problems that can cause mold growth in the kitchen and bathroom. In more tightly constructed homes, mechanical ventilation may be required to promote healthy home air quality.

Heat recovery ventilation (HRV) systems supply a continuous supply of fresh air into homes while exhausting an equal quantity of stale, contaminated air. These systems transfer heat from the exhaust air to the intake air, saving energy. The intake air is filtered, removing some common air contaminants.

Zehnder heat recovery ventilation (HRV) systems are the most energy-efficient HRV systems on the market and some models are certified by the Passive House Institute. Zehnder ComfoAir HRV systems have fine filters available that can remove pollen, dust, smog particles, and bacteria.

Many homes are equipped with exhaust fans in the bathroom and range hoods in the kitchen. Although they can effectively remove excess moisture, cooking fumes, and other contaminants, they are less than ideal. Exhaust fans remove conditioned air from the home without recovering the heat or coolness, driving up energy bills. These units only exhaust air, so makeup air must enter through gaps and cracks in the home’s exterior to replace the air that is lost. Depending on where this air originates, it can cause home air quality issues and uncomfortable drafts in the winter. It is important that exhaust fans vent air to the outside and not into the attic where they can cause other indoor air quality issues in the home.

Feature photo by Daria Shevtsova from Pexels. Originally published on August 21, 2018, this article was updated in June 2020.

By Sarah Lozanova

Sarah Lozanova is an environmental journalist and copywriter and has worked as a consultant to help large corporations become more sustainable. She is the author of Humane Home: Easy Steps for Sustainable & Green Living, and her renewable energy experience includes residential and commercial solar energy installations. She teaches green business classes to graduate students at Unity College and holds an MBA in sustainable management from the Presidio Graduate School.