The Ultraviolet Index (UVI)
The Ultraviolet Index (UVI) is an international, scientific measure of the level of ultraviolet radiation (UVR) reaching the Earth's surface. It also informs our sun protection advice. The higher the number the greater is the need for protection. New Zealand has particularly high levels of UVR during daylight saving months. UVR levels also vary throughout the day.
Whenever UV radiation levels reach 3 (moderate) and above, sun protection is required. At that level UV radiation is intense enough to damage the skin and contribute to the risk of skin cancer. From September to March, UV radiation levels are 3 and above for most of the day in New Zealand (and for even longer periods in the north).
Particular care should be taken between 11 am and 4 pm when UV radiation levels reach their peak.
