John Ogden-McKee, a self-described "extremely clean person," has a penchant for filtration. In his home in Dallas, Ogden-McKee, 39, uses five air purifiers with built-in HEPA (short for high-efficiency particulate air) filters — one in every room but the kitchen — drinks water from a filtered container, and fills his drinking glasses with cubes created in an ice maker with a filtration component. He replaces the MERV 13 filter in the air conditioner on the first of every month; as soon as the "change filter" light on the other devices illuminates, he swaps out the used filter for a new one. "We just always have extra," he says of his stash of assorted filters, which he keeps stored in a closet. "I can't stand any chaos."
Recently, Ogden-McKee discovered a crack in his highly filtered facade. While cleaning the water fountain for his kittens, Push Pin and Paperclip, Ogden-McKee accidentally discovered the device had a filter — one with four months' worth of cat water grime. "It was almost like this horror that was in my house that I had no idea about," Ogden-McKee says.
Over the course of a day, you're likely to encounter any number of filters: furnace/air conditioning filters (they're the same filter if your home has central AC), vacuum filters, water filters, car cabin air filters, humidifier filters, dishwasher filters, cat fountain filters. The pandemic helped raise the status of air filters as public health officials touted the benefits of ventilation and air purifiers in clearing SARS-CoV-2 in the air. Designed to remove contaminants like dust, pet hair, and chemicals from your air or water, filters need to be cleaned or replaced regularly or the devices they aid won't function as necessary. Even more crucially, air filters help prevent all the gunk in the air in the home from getting into your body.
"Indoor air can be more polluted than air outside," says Kelsey Hei, a 3M Filtrete Brand application engineer. "With our homes being built more airtight, there isn't as much air circulation to capture and remove particles from your home's air without the help of heating and cooling systems or air purifiers, aside from opening windows and doors."
However, most people don't regularly swap out or clean filters on their appliances, says Kelly Winslow, the director of engineering at EnviroHome, which specializes in environmental engineering and indoor air quality. "People abuse filters," Winslow says, "because they just put it in, leave them in, and think the job is done. A filter is a temporary solution."