"Canada Wildfires Cause Air Quality Concerns Across North America"
As smoke from Canadian wildfires reaches the east coast of the US, New York City's air quality has become the second worst on Earth. To protect against the health hazards of the hazy air, residents can build their own air filter using a box fan and four AC air filters rated MERV 13-16 or MPR 1200-2800. By taping the filters together in a square and placing the fan on top, the filter can effectively strain 2.5um smoke particles from the ambient air.