You might think of gas masks as clunky military-looking devices. But in the near future, we may need to rely on these filters as part of our everyday lives. In addition to emerging diseases, wildfire frequency has more than tripled, and climate change has increased toxic ground level ozone. So how do these masks work, and can they protect us from airborne threats? George Zaidan investigates. Lesson by George Zaidan, directed by Michael Kalopaidis, Zedem Media.