What does clean air smell like?

For many people, the smell of clean air is the scent of the air outdoors after a thunderstorm. That scent is so alluring that the makers of one particular air cleaner describe their machine as a “thunderstorm in a box.”

What the makers of the “thunderstorm in a box” neglect to mention is that the fresh, post-storm (and also pre-storm) aroma they promote is largely the scent of ozone, deliberately produced by their “air cleaning” machine. In a thunderstorm, ozone originates from nitric oxide that is produced by the electrical charge in the storm. The nitric oxide combines with other airborne chemicals to form ozone, which is pushed close to the ground by the storm.

For many people, the smell of clean air is the scent of the air outdoors after a thunderstorm. That scent is so alluring that the makers of one particular air cleaner describe their machine as a “thunderstorm in a box.”

What the makers of the “thunderstorm in a box” neglect to mention is that the fresh, post-storm (and also pre-storm) aroma they promote is largely the scent of ozone, deliberately produced by their “air cleaning” machine. In a thunderstorm, ozone originates from nitric oxide that is produced by the electrical charge in the storm. The nitric oxide combines with other airborne chemicals to form ozone, which is pushed close to the ground by the storm.