Photochemical smog production
Photochemical smog is a type of air pollution produced when sunlight acts upon motor vehicle exhaust gases to form harmful substances such as ozone (O3), aldehydes and peroxyacetylnitrate (PAN).
Photochemical smog is an atmospheric condition that produces severe eye irritation and poor visibility, to name just two of the effects. Three ingredients — energy from a light source (ultraviolet), hydrocarbons, and nitrogen oxides — are needed for photochemical smog to be formed.
Photochemical smog formation requires the following conditions:
- a still, sunny day
- temperature inversion (pollutants accumulate in the lower inversion layer)
Ozone causes breathing difficulties, headaches, fatigue and can aggrevate respiratory problems.
The peroxyacetylnitrate (CH3CO-OO-NO2) in photochemical smog can irritate the eyes, causing them to water and sting.
