The alteration of the air's normal composition is a fact that has occurred even before Man appeared on the Earth. Volcanoes, earthquakes, forest fires, emissions from lakes, etc, were and are natural sources of emissions that release large amounts of substances to the air that do not form part of its normal composition.

The spectacular development of mechanical transport and the increase in well-being have also been important properties since the start of the last century. Together with industrialisation and the well-being brought about by the increased standard of living, one of the greatest problems faced by humanity has appeared: air pollution.

What is air pollution ?

Air pollution means the presence in the atmosphere of materials, substances or forms of energy that cause serious nuisance, risk or harm to persons' safety or health, to the environment and other goods of whatever nature. When these materials or sources of energy endanger (or threaten to endanger) our health, well-being or resources, either directly or indirectly, they are called pollutants.