The ozone is present in the highest zones of the atmosphere; the oxygen (O2) changes
itself into ozone (O3)
thanks to the action of the ultraviolet rays coming from
the sun
and the cosmic rays.This gas has the task to protect us from the dangerous action that
these rays can have on our bodies.The ozone works as a large filter which blocks the way
of the radiations that are injurious to human
beings life on the earth.Besides when it
is very hot and sunny and the pollution in the air is very high, the ozone is present in the atmosphere even at low
altitudes. Here it combines with the other polluting
substances
and becomes poisonous for the man and for the environment. In the period taken into
consideration in Umbria this substance has a
concentration next to or sometimes even higher than the limit values.