Huffman now recommends households explore far cheaper methods to monitor outdoor and indoor air quality. To help manage his asthma, he keeps a careful eye on the EPA's fire and smoke map, which tracks nationwide smoke plumes and air quality readings.
To monitor indoor air quality, he purchased an egg-shaped monitor from PurpleAir, which now sits on a table inside the front door of his home in Centennial. It glows green, yellow or red depending on the severity of suspended particulates.
Basic senses are an even cheaper alternative. Colorado air forecasters recommend assuming air quality is unsafe if you can’t clearly see something less than five miles away. Smells can also serve as evidence of wildfire smoke, but shouldn’t always be trusted. Christine Wiedinmyer, an air quality scientist at the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder, said smoke from far-off fires doesn't carry an odor but can be dangerous nonetheless.
Buy or make a high-quality indoor air filter
Huffman has a portable air purifier in his living room to help remove wildfire smoke. He demonstrated its efficiency by turning on a popcorn popper with a filthy heating element.
Smoke filled the room as his indoor air monitor turned an alarming red. The purifier then pulled the smoke closer with a gentle hum, bringing particulates back to safe levels in about 30 seconds.
When shopping for an air purifier, Huffman said it should have HEPA filtration to remove particles. He recommends against anything with "plasma" or "ionization," which doesn't do much about wildfire smoke and can add other pollutants to the air.
If a $200 machine is out of the question, another option can be fashioned from a box fan taped to one or several furnace filters of a MERV13 grade or higher. The device, called a Corsi-Rosenthal Box, was born after a mechanical engineer tossed out the idea on Twitter.
Huffman installed a number of these contraptions around his house and donated others to his kids' classrooms. Instructions are available online.
Seal openings and run your air conditioner (if you have one)
Wiedinmyer recommends sealing doors and windows to prevent any wildfire smoke from making it into the home. If you have an air conditioner, replace the filter then set it to recirculate air to further cut indoor pollutants.
Not all homes have the luxury of air conditioning. Huffman has a swamp cooler, which he prefers for its energy efficiency. Because those systems rely on circulating cooled external air, they aren’t nearly as well equipped to handle poor outdoor air quality.
"It's just pushing wildfire smoke into our house pretty efficiently, which is really unfortunate," Huffman said.
He doesn't see an easy way around the problem at the moment. On smoky days, he said households that use swamp coolers or open windows will need to decide if welcoming the bad air is worth it.
Wear a high-quality mask
When you have to head outside on a smoky day, Huffman recommends wearing a high-quality N95 mask to protect against particulates. Don’t bother with cloth masks, though; their mesh isn’t fine enough to stop the bits of wildfire smoke, he said.