An Expert Guide to Buying an Air Purifier for Smoke
Photo by Borri Studio
Summertime is usually a time here in the United States to have fun with friends and family in the great outdoors. However, it seems in recent years that our summer air is increasingly filled with wildfire smoke! As the air fills with the hazy cloud of smoke, you find yourself retreating to the safety of your home, overwhelmed with a myriad of recurring symptoms: headaches, red and itchy eyes, coughing, sore throat, chest pain, shortness of breath, dizziness, and fatigue. I don’t know about you, but I’m tired of being tired! And I sure don’t want to develop lung disease! But just how much better off are you indoors?
Wildfire smoke can make anyone sick, but people with respiratory diseases such as asthma, Chronic Obstructive Pulmonary Disease (COPD), or heart disease are especially at risk. So too, are kids, pregnant women, and first responders.
According to the EPA (Environmental Protection Agency), in the last several years, a growing body of scientific evidence has indicated that the air within homes and other buildings can be more seriously polluted than the outdoor air in even the largest and most industrialized cities. Other research indicates that people spend approximately 90% of their time indoors. Thus, for many people, the risks to health may be greater due to exposure to indoor air pollution rather than outdoor.
How Wildfire Smoke Enters the Home
Outdoor air enters and leaves a house through infiltration, natural ventilation, and mechanical ventilation.
In a process known as infiltration, outdoor air flows into the house through:
- openings
- joints
- cracks in walls, floors, and ceilings
- around windows and doors
In natural ventilation, air moves through opened windows and doors. Air movement associated with infiltration and natural ventilation is caused by air temperature differences between indoors and outdoors and by wind.
Finally, there are a number of mechanical ventilation devices, from outdoor-vented fans that intermittently remove air from a single room, such as bathrooms and kitchens, to air handling systems that use fans and ductwork to continuously remove indoor air and distribute filtered and conditioned outdoor air to strategic points throughout the house.
The rate at which outdoor air replaces indoor air is described as the air exchange rate. When there is little infiltration, natural ventilation, or mechanical ventilation, the air exchange rate is low, and pollutant levels can increase. Regardless of whether you live in a single-family home or an apartment, the same hazardous conditions can occur.
So, just retreating to the safety of the “not so great” indoors isn’t the best solution. Wildfires put particulates and odors into the air, and these tiny smoke particles are often smaller than 10 microns—that’s smaller than a speck of dust; you can’t even see it with the naked eye! They’re so small that the standard home filters, like the ones that you change out in your home heating and air conditioners (HVAC), can’t remove them. So, what’s a family to do? There is a solution! Read on as we break down how to keep you and your loved ones healthy during fire season and throughout the year!
Let’s find the most effective ways to protect your lungs and eliminate wildfire airborne particles and smoke odors from your home's air. Because of these environmental factors, more and more families are looking toward air purification.
What Is Home Air Purification?
Quite simply put, an air purifier or air cleaner is a device that removes contaminants from the air in a room to improve the air quality. They work by passing your home air through specially designed filters that are designed to remove pollution and odors from your home.
Here’s a list of air filters commonly used for various types of air purification:
- HEPA filters
- UV light filters
- Electrostatic filters
- Washable filters
- Media filters (carbon)
- Spun glass filters
- Pleated filters
Filter Types
HEPA
Remember earlier when I told you that wildfire smoke and odors could be as small as 10 microns? Well, the best way to eliminate these pollutants is with a true HEPA (high-efficiency particulate air) filter. They are able to remove 99.97% of allergens and pollutants as small as 3 microns! That’s 3/1000th of an inch! It’s easy to see how these purifiers are able to remove the odor, harmful chemicals, and microscopic particles from wildfire smoke—they trap all these tiny particles that are smaller than a speck of dust and remove them from the air.
Media (Carbon) / Activated Charcoal
The best air purifier for smoke is one that uses a combination of HEPA filtration and carbon filtration. A charcoal filter adds an extra level of odor removal to the system. Carbon air filters are used primarily to remove gasses and volatile organic compounds (VOCs) from the air. These are released from common household products but are also released into the air by wildfires. Ideally, you want to choose a purifier with an activated carbon filter, as this type of carbon filter is able to absorb more than a standard carbon filter sheet. In combination with HEPA filtration, you’re able to cover all the bases when it comes to home air safety. This type of purifier with multiple filtration stages is great for odor removal caused by tobacco smoke.
Electrostatic
Electrostatic filters use electricity to charge the particles in the air. The charged particles are then attracted to an oppositely charged filter media and are trapped there.
I feel a word of caution should be added here. While electrostatic systems may be safe for most adults, a byproduct of electrostatic filters is that they generate ozone gas. Studies have shown that ozone in high doses can be harmful. Not all ionic purifiers produce ozone, so keep an eye out and avoid the ones that do. This is especially important if the purifier is to be used in a baby's room. A good way to determine this is if the purifier is CARB (California Air Resource Board) certified, as California has strict regulations on ozone production and which purifiers are certified. Check out California Air Resources Board Website for an explanation of the guidelines and a list of certified purifiers.
UV Light
UV light filters use ultraviolet light to kill harmful pathogens. Smoke particles are not only harmful in and of themselves but also potential pathogens (viruses, bacteria) can attach themselves to a smoke particle, so UV light will kill these “hitchhikers.”
Pleated, Washable, and Spun Glass Filters
Everyone should be familiar with these types of filters when looking for an air purifier for smoke. These are the ones that are commonly used in home heating and air conditioning systems. Standard pleated filters are disposable and washable filters may be removed and cleaned to use multiple times. Often purifiers come with washable pre-filters and sometimes carbon filters that help extend the HEPA filter’s life. They should be cleaned often (every two months) during wildfire season and also just as frequently in homes where cigarette smoke is present.
The Best Option?
In summary, remember that the best air purifier for smoke has a combination of HEPA and carbon filtration.
An added bonus of an air purifier with a true HEPA filter is that it also removes dust, pet dander, gases, fine particles, pollen, bacteria, cigar smoke, cigarette smoke, chemicals, germs, and mold spores!
So, now that we’ve determined all the particulate matter that HEPA filtration can eliminate to help keep your family safe, let's review what specifications to look for when deciding which one is the right home air purifier for you.
What to Look for When Buying a Purifier for Smoke
What else should be considered when trying to remove wildfire smoke from the home? A clean air delivery rate (cadr rating) is key. You want a purifier that will be able to handle the square footage of the room that your purifier is in. Another specification you may want to look at is Air Changes Per Hour (ACH or ACPH). ACH rating will tell you how many times a purifier can clean a room in square feet 4.8x per hour. The ideal rate for anyone dealing with breathing issues, asthma, allergies, or smoke is 4x per hour in the space where you are looking to keep clean. Look for models that have the appropriate coverage area, especially for a larger room.
Fan speed is another key variable. Models with varying fan speeds allow you to control how quickly you’re able to turn the air around in a room and subsequently improve smoke removal. You may have an elderly family member popping by and want to crank up the fan speed to get the air purified quickly! Many purifiers also have an auto mode with an air quality sensor that lets the air purifier decide which fan speed is the best based on your indoor air quality. And while you may not want to rely on the auto mode all the time, especially if you're dealing with smoke, it's a nice feature to have that can save you some money in the long run.
You can look for minimum efficiency reporting values (MERV) for the purifier in question. This is the ability of the unit to capture particles between 0.3 and 10 microns. The higher the MERV rating, the better the purifier is at trapping specific types of particles. MERV is traditionally used as an HVAC system rating, and purifiers are generally not tested against MERV standards, so don't be too concerned if a MERV rating is not available. Also, HEPA filters are the equivalent of MERV 17 filters.
In addition to the type of filter technology, other things to consider include noise levels (indicated in decibels), energy efficiency (energy star rating), and cost of maintenance and filter replacement. These values should be provided by the manufacturer, along with any other certifications the purifier has.
Another great feature available is plug-and-play technology. This allows you to connect your home purification system to your phone or “smart home” hub via Bluetooth or your home's wifi network. This, of course, allows you to make changes and monitor the efficiency of the unit at all times. And if you're bothered by bright lights or noise, a sleep mode may be a must-have feature for you.
Styles of Purifier Units Available
Console
- Greatest square footage
- Strongest filtration
- Sometimes wall mountable
Tower
- More portable than a console
- Great for the office or moving around the home
Table-top
- Great for small spaces
- Budget-friendly
- Easily portable
- Affordable filter replacements
Best Brands
- Winix
- Molekule
- Rabbit Air
- Austin Air
- Fellowes AeraMax
- Allen
- Aura Air
- Levoit
Closing Thoughts
So far, we have talked about what to look for and what to avoid to keep your family safe this wildfire season. We’ve looked for a system that combines HEPA and carbon filtration. We want to make sure that the air purifier is capable of handling the size of the room where it will be installed. We spoke of what specs to look for and additional connectivity options. I encourage you to take the info provided and get with an Air Purifier Expert and talk to them about the needs of your home and family. Indoor air quality is important!
Until next time, here’s wishing everyone a safe and healthy fire season! I hope that the above info helps you breathe easy! (pun intended)