TikTok Is Teaching People to Make DIY Air Purifiers

East Coast residents were caught off guard this week by the raging wildfires in Canada that unexpectedly blanketed many parts of the eastern United States in thick, hazy smoke. Because wildfire smoke has become an unpleasant but common reality in recent years for those living on the West Coast, some are educating the other side of the country on how to make a DIY air purifier that can be a life saver in these trying times.

And all you need to make a surprisingly effective DIY air purifier is a box fan, four air filters, and a lot of duct tape—all for under $100.

In a TikTok video that’s been viewed over 600,000 times, Seattle resident Angel Robertson shared one New Yorker’s attempt at filtering smoke by putting a towel under the door. As she explained, Pacific Northwesterners have faced the same issue in the spring and summer to due wildfires in California and Canada, and the hack works even better than store-bought air purifiers.

You simply duct tape the four air filters together to make a box shape, and then place the fan on top, pointing up.

“It works in a couple hours—you can tell the difference in one or two—and will save your life with really smoky days,” Robertson says in the video. “It does a lot better than the normal air filters.”

@byangelann

#stitch with @???????????????????????? ???????????????????? We typically hve this tunning all spring/summer for fires in the PNW and it works like a charm. ❤️???? #nycsmoke #canadianfires #airpurifier #diyairpurifier

♬ original sound – Angel Ann

Th technique is known as the Corsi-Rosenthal method, which was a collaboration between Richard Corsi, dean of the College of Engineering at the University of California at Davis, and Tex-Air Filters CEO Jim Rosenthal.

As the story goes, Corsi had conceived the design during the unprecedented 2020 California wildfires because he wanted to create an inexpensive, effective purifying method that average Americans could afford. After he tweeted a sketch of the contraption one night, Rosenthal took the design and ran with it.

In addition to smoke, the devices are also surprisingly effective at filtering out other particulate matter such as pollen, dust, pet dander, dirt, viruses, and allergens.

“When you have to seal up a building and reduce the amount of air flow coming in and when you have to spend a lot of time indoors, this is where portable air cleaners can really make a difference in your life,” Corsi told the Associated Press.

And it’s already helping countless people. Unfortunately, as climate change continues to accelerate, this information will likely only become more valuable.