6.3 Photochemical smog

Bad ozone

A toxic gas and an oxidizing agent. It damages crops and forests, irritates eyes, can cause breathing difficulties in humans and may increase susceptibility to infection. It is highly reactive and can attack fabrics and rubber materials. Is found in the troposhpere.

How is bad ozone formed

Nitrogen dioxide can also absorb sunlight and break up to release oxygen atoms that combine with oxygen in the air to form ozone.

Sources of bad ozone

Sources are:

• Transport

• Cooking

• Dust from construction sites and roads

• Heating

• Power generation

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Secondary Pollutants

are produced in the air by the interaction of two or more primary pollutants

Ex:

• bad ozone

Somg components

primary + secondary pollutants

• bad ozone is the main pollutant

Temperature inversions

when cold air is trapped under warm air. Cold air does not move or sinks in from surrounding hills. ​