Synopsis Earth is truly a marvelous third planet and 93,000,000 miles (150,000,000 km.) from the sun. Earth’s atmosphere is a gaseous envelope that surrounds the earth planet. It consists of a mixture of gases such as nitrogen, oxygen, carbon dioxide, traces of noble gases (argon, krypton, xenon neon and helium), water vapour and small amount of ammonia, ozone, organic matter, various salts and suspended solid particles. Air is one of the most important constituents of man’s environment. It is calculated that a man breath about 22,000 times a day inhaling about 16 kg of air by weight. Therefore, clean and pure air is very essential for his health and survival. Any change in the normal composition of the air either qualitative or quantitative that may affect adversely the living system, particularly the human life inevitably cause air pollution.