Understanding wildfire smoke
According to Climate Central, “Wildfires burning within 50-100 miles of a city routinely caused air quality to be 5-15 times worse than normal. Smoke generated by forest fires is comprised of water vapor, particulate matter and a variety of gases, including formaldehyde, benzene, toluene, carbon dioxide, sulfur dioxide, nitrogen oxide, carbon monoxide, and volatile organic compounds (VOCs)."
These materials each fall into one of two different groups of pollutants: particles or gases. Each group requires a different method of filtration to successfully remove it from the air.
As stated by the Environmental Protection Agency (EPA), “Fine particles...particles generally 2.5 µm in diameter or smaller represent a main pollutant emitted from wildfire smoke.. [and] are [the] greatest health concern. This group of particles also includes ultrafine particles, which are generally classified as having diameters less than 0.1 µm."
Best air purifiers for wildfire smoke
A portable room air purifier can you help manage poor indoor air quality caused by wildfire smoke, as recommended by the EPA in their clean room guidelines. Not all air purifiers are equipped for smoke removal and there are several factors to consider. We suggest evaluating an air purifier’s performance in removing smoke related pollutants by considering the three points below.
Blueair recommends using a combination particle and carbon filter. The activated carbon-based filters are effective in removing fine particles as well as smells and ozone created by the wildfires.
Look for the Clean Air Delivery Rate (CADR) for smoke. The higher the CADR number for smoke, the more effective the air purifier is at removing the harmful fine particles in smoke.
CADR indicates the air purifier’s ability to produce clean air by removing airborne particles at various sizes and represents the sizes with three common air pollutants: smoke, dust, and pollen. It is the most comprehensive performance metric for air purifiers since it accounts for both its ability to remove impurities and the size of its airflow.
Make sure you have an air purifier certified by the Association of Home Appliance Manufacturers (AHAM). All AHAM Verified® air purifiers are given a recommended room size.
It is important to choose an air purifier that can accommodate the volume of air in the room where you will place it. This ensures there is enough airflow (measured in ‘air changes per hour’ or ‘ACH’) to reduce pollutant levels consistently and over a long period of time.
Blueair’s HEPASilent™ technology uses a combination of electrostatic and mechanical filtration to charge smoke particles entering the air purifier
with a low current – which in turn makes them stick to the filter media more effectively. Carbon within the filters helps to absorb gases and odors.
HealthProtect™ and Classic
Especially during wildfires, recommended air purifiers from the HealthProtect™ and Classic families feature activated carbon filters equipped to absorb higher levels of gases and odors present in smoke, as well as high Clean Air Delivery Date (CADR) values for smoke. Their relatively low energy consumption is also important when you need to continuously run the air purifier 24/7, especially during a wildfire. Our HealthProtect models also contain SmartFilters that accurately track real time usage, so can tell you exactly when you need to replace based on how polluted your air has been.
Blue Pure Auto
All Blue Pure Auto models have excellent smoke particle removal (the element which poses the greatest health threat) and consume relatively low amounts of energy – which again is an important consideration if you need to run them 24/7. While they all feature an activated carbon layer to reduce odor & gases, the 211+ Auto filter can most effectively reduce gas and odor from wildfire smoke. The 411 Auto and 311 Auto have lower removal rates of gases, chemicals and odors.’
Tips and tricks: preparation and what to do during wildfires
Ensure they are in working order and replace batteries if necessary.
Consider purchasing a few particulate respiratory masks to wear outside when needed.
Purchase extra filters to ensure maximum performance. Plan to replace before and after wildfire season. Select filters with the highest MERV rating recommended by your HVAC manufacturer.
As with HVAC filters, replacing your air purifier filters before and after wildfire season can help to maximize performance. Filters that also contain carbon are best to help remove particles and gases that make up smoke.
It is important to run your air purifier 24/7, especially during a wildfire, as polluted air is constantly entering the room through ventilation or poorly sealed windows. Additionally, you can change up the speeds for more effective removal, running your portable air purifier on high and then on low fan speed to effectively remove both smoke and gases/odor.
Smoke particles are most effectively filtered out on highest fan speed so the particles are quickly captured in the filter media. However high air speed negatively impacts gas absorption, so alternating to a slower fan speed is recommended to let the carbon have longer contact with gases to absorb them more efficiently.
Conditions can change quickly, so you should always be prepared to evacuate if necessary. Follow your local news, the AirNow website, or your state air quality website for up-to-date information.
If there is an active fire in your area, or if the Air Quality Index indicates smoke levels are unhealthy and forecasted to remain there, local authorities may advise you to stay indoors or create a clean room rather than evacuate. Setting up a clean room at home can help reduce your exposure to dangerous or unhealthy wildfire smoke while indoors.
Everyone can benefit from spending time in a clean room during a wildfire, but it may be most helpful for sensitive individuals like the very young, very old, and people with heart or lung problems. Read the EPA’s full clean room guidelines here.