What is Ozone (O3)?
Ozone is a gas that forms in the atmosphere when 3 atoms of oxygen are combined. It is not emitted directly into the air, but at ground level is created by a chemical reaction between oxides of nitrogen (NOx), and volatile organic compounds (VOC) in the presence of sunlight. Ozone has the same chemical structure whether it occurs high above the earth or at ground level and can be “good” or “bad”, depending on its location in the atmosphere.
