22 What is the UV index? What does the UV index scale range from?

The UV index scale is measurement of the strength of harmful ultraviolet radiations of the sun and its effects on the human skin upon direct exposure.

This scale is recognized by the international health organization, and its varies from 0 to 11, it is the normalized intensity radiation from the sun, that comes through the upper atmosphere, a UV scale reading 0 to 2.9 means a safer radiation levels, whereas 3 to 5.9 claims moderate risk but above 6 alarms a warning case and skin and eyes are needed to be protected.

The UV index scale normally ranges 0 to 11.