Acid rain is precipitation of drops of water containing absorbed gases: sulfur dioxide (SO2),
nitrogen oxides and other gases that produce acids in reaction with water as well as products of their reactions in the atmosphere - weak solution of sulfurous acid (H2SO3) and much more dangerous acids: sulphuric acid (H2SO4) and nitric acid (HNO3).
Acid rain is formed mainly in areas where the atmosphere is exposed to long-term emissions of sulfur dioxide and nitrogen oxides, both from natural sources, e.g. active volcanoes, as well as artificial - exhaust gases from the combustion of fuels containing sulfur - lignite and coal.
Acid rain have a negative impact on flora and fauna. They are undoubtedly the cause of many respiratory diseases. Acid rain greatly accelerates the corrosion of various metal constructions and monuments.
Preventing the occurrence of acid rain is based on building installations catching the sulfur and nitrogen oxides from the exhaust gases emitted into the atmosphere as well as on reducing the combustion of fuels containing sulfur and its compounds, mainly lignite and coal.
Preventing the occurrence of acid rain should be international, because often acid rain hit areas located far away from sources of air pollution.