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  • Winter Air Quality Q&A: How Spending More Time Indoors Affects Your Air

    Learn how winter changes your indoor air quality and how you can respond.

    Woman looking out the window

    • With the wintry chill comes more time spent indoors—especially this year. No matter what the weather is like in your city, chances are you’re at home more than ever. Even without a pandemic, Americans spend up to 90% of their time indoors, which might leave you wondering: How does that much time inside affect my indoor air quality?1 This Q&A is here to help you get the lowdown on how you can improve air quality at home this winter.

      Q: Does indoor air quality change in the winter?
      A: Yes—when outdoor air quality changes, it affects indoor air quality.

      Changing seasons have a big effect on air quality, indoors and out. When winter rolls around, the temperature drops and changes the way air moves. Cold weather causes most of the warm air in the atmosphere to rise, trapping cold air—and pollutants like smog and ozone—in the air we’re breathing.² Additionally, the cold weather means more people are heating up their cars or using wood-burning fireplaces, which can release smoke and vehicle exhaust into the air.² These pollutants can easily make their way into your home when doors open, through drafty windows, on pet fur and even on our winter clothing.

      Q: Does indoor air quality change when I spend lots of time inside?
      A: Yes. The more time you spend inside, the more opportunities there are to introduce pollutants.

      Did you know we can pollute our indoor air without even thinking about it? The more time spent at home, the more frequently you’re cooking, cleaning, running water and more. Cooking, especially with oil on the stovetop, can release exhaust into the air, and harsh cleaning products can give off harmful fumes.³ Steam produced from running water in the kitchen or shower, or using a dryer can increase mold spores in your air. Even day-to-day activities like burning candles or brushing your pet can release unwanted particles into the air.

      Q: How can I take care of indoor air when pollution risks are higher?
      A: Lots of ways!

      Even though there are lots of ways pollution can be introduced into the air when you’re spending more time at home, you can reduce the amount of airborne particles in your air. Choose an HVAC filter that helps capture the particles that concern you. For instance, tech-forward Filtrete™ Smart Filters can trap tiny particles such as allergens, bacteria and virus-sized particles, and track filter usage in real time so you know exactly when to change your filter. For extra filtration in rooms where you need it most, portable air purifiers can also give you cleaner, fresher indoor air.

      Increasing ventilation (air flow in your home) is another way to improve indoor air quality. Use ceiling fans, run exhaust fans in the kitchen and bathroom—even slightly opening a window can help to let some fresh air in if it’s a good outdoor air quality day. If you have a central HVAC system, have the ventilation system professionally inspected each year to ensure it is functioning properly.

      And don’t forget other air quality improvement tasks: stick to a frequent dusting routine and keep an eye on winter outdoor air quality.


      1. https://www.epa.gov/report-environment/indoor-air-quality

      2. https://scied.ucar.edu/learning-zone/air-quality/how-weather-affects-air-quality

      3. https://emergency.cdc.gov/agent/chlorine/basics/facts.asp

      Related reads

      1. https://www.filtrete.com/3M/en_US/filtrete/home-tips/full-story/~wintertime-benefits-of-an-air-purifier/?storyid=e059916c-efa3-4283-908a-2b6719146b67

      2. https://www.filtrete.com/3M/en_US/filtrete/home-tips/full-story/~prevent-home-invading-pollutants/?storyid=3a9d1422-0df7-466f-962d-ab2c00b7756c