With wildfires on the rise, it’s natural to worry about their impact.1 Even when they’re not directly threatening an area with flames, these infernos continually spew massive amounts of toxic pollutants into the atmosphere.2 This smoke can travel huge distances, tainting the air quality over vast spaces.  

Any problem that affects breathing quickly becomes difficult to ignore. In this blog post, we’ll explore the detrimental effects of forest fires on indoor air quality and provide some realistic tips on protecting indoor air during the wildfire season.   
The Impact of Wildfires on Indoor Air Quality   
Forest fires are belching unprecedented amounts of smoke, ash, and other harmful pollution into the atmosphere.3 From there, these materials easily make their way indoors through open windows, doors, and inadequately filtered ventilation systems. This infusion compromises indoor air quality (IAQ) – undermining the health of occupants within homes, offices, and other structures.   

It’s scary that, in addition to the “fresh air” of the outdoors becoming unsafe due to volumes of smoke, there’s no escape if contaminants infect indoor spaces, too. Prolonged exposure to soiled environments can result in health risks, including respiratory issues, eye irritation, headaches, heart diseases, and the exacerbation of existing conditions such as asthma and allergies.4   
5 tips for protecting IAQ from wildfire smoke  

  1. Don’t let pollutants in: During wildfire season, do your best to keep windows, doors, and vents closed with tight sealing. From there, it’s a good idea to keep heating, ventilation, and air conditioning (HVAC) systems on “recirculate mode”. This helps keep smoke and other unwanted substances out.  
  2. Monitor your environment: Knowing exactly how dirty or clean your environment is makes a huge difference when choosing when to take action. One solution is the Aranet4 HOME wireless air quality monitor tracking CO2, temperature, relative humidity, and atmospheric pressure. CO2 is a common benchmark; the higher carbon levels are within a building, the worse the air quality is.

    Aranet4 HOME indoor air quality monitor

  3. Reduce outdoor exposure: When conditions are poor and smoke is thick, it’s a good idea to limit activities outside. Instead, take your interests and hobbies indoors – preferably somewhere with an intact and well-maintained filtration system. In addition to directly breathing unhealthy air, please be aware that pollutants can hitch a ride on clothing, shoes, etc., and slip indoors. If you must go outside when things are smokey, try to wear a mask with a sufficient protection rating like the N-95.
  4. Ensure proper ventilation: While simply opening windows and doors may not be an option, you can use devices like kitchen and bathroom exhaust fans, energy recovery ventilators (ERV), heat recovery ventilators (HRV), and air purifiers: For the best results, use quality equipment fitted with high-energy particulate air (HEPA) filters. 
  5. Keep your space clean: Simple sanitation practices (like vacuuming) make a large difference in the accumulation of unwanted substances. However, try to avoid dry dusting. This simply stirs up particles from surfaces, causing them to resettle elsewhere after floating for a bit. If there’s a particularly problematic fire nearby, it may be worth maintaining a special clean room in the home with additional protective measures. This can include sealing the space off from other rooms and using air purifiers designated for that specific space. This way, inhabitants can enjoy a safe zone, even if pollution invades other spaces.6  



  1. New Data Confirms: Forest Fires Are Getting Worse. https://www.wri.org/insights/global-trends-forest-fires 
  2. Chapter 4 Chemical Composition of Wildland Fire Emissions. https://www.sciencedirect.com/science/article/abs/pii/S1474817708000041
  3. Air pollution in US from wildfire smoke is worst in recent recorded history. https://www.theguardian.com/environment/2023/jun/08/air-quality-record-smoke-hazard-wildfire-worst-day-ever-canada-new-york 
  4. Wildfire smoke impacts on indoor air quality assessed using crowdsourced data in California. https://www.pnas.org/doi/10.1073/pnas.2106478118
  5. N95 Masks Helped Protect Against the Coronavirus. They Also Work Against Wildfire Smoke. https://www.nytimes.com/2023/06/07/us/masks-wildfire-smoke-air-quality.html
  6. Create a Clean Room to Protect Indoor Air Quality During a Wildfire. https://www.epa.gov/indoor-air-quality-iaq/create-clean-room-protect-indoor-air-quality-during-wildfire   

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