The Ultraviolet (UV) Index is a measure of the intensity of the sun’s ultraviolet radiation in the sunburn spectrum. As the UV Index increases, the sun’s rays can do more harm to your skin, eyes and immune system. This is why it is important that you listen for Environment Canada’s daily UV Index in your local weather forecast. It will help you gauge what precautions are necessary to protect you and your family from harmful UV rays.
Ultraviolet (UV) rays are the sun rays that can cause sunburn. Long-term exposure to UV rays has been associated with skin aging, eye cataracts, weakening of the immune system, and skin cancer.
The amount of UV that you receive depends on both the strength of the sun’s rays (measured by the UV index) and the amount of time you spend in the sun. The higher the UV Index number, (the UV Index is a 0 - 11+ scale) the stronger the sun’s rays, and the greater the need to take sun safety precautions.
Environment Canada’s UV Index Values & Sun Protection
- Environment Canada has developed a set of sun protection messages for each category of the UV Index.
- It is divided into five levels: Low (0-2), Moderate (3-5), High (6-7), Very High (8-10), and lastly, Extreme (11+).
- These categories refer to the strength of the sun’s UV rays. The stronger the sun’s rays are, the greater the need to take precautions.
- Read more about Environment Canada’s recommended sun protection actions for each level of the UV Index.
The UV Index and Ozone (Environment Canada)