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Sun and UV

Child with sunscreen on his face

No one is completely safe from the sun. In Canada, sunlight is strong enough to cause skin cancer, premature aging of the skin and harm to the eyes.

Skin cancer is the most common type of cancer, and it's also one of the most preventable. UV radiation causes about 90% of melanoma cases. The incidence of melanoma skin cancer has increased significantly among men and women during the past 25 years.

Enjoy the sun safely: protect your skin and protect your eyes. Reduce your risk of skin cancer by using SunSense and talk to your doctor about any changes to your skin.

There are 3 types of ultraviolet (UV) rays:

  • Ultraviolet A rays (UVA) make up most of the sun's natural light. They can penetrate deep into the skin, causing wrinkles and premature aging of the skin.
  • Ultraviolet B rays (UVB) are the main cause of sunburn. They are nearly 1,000 times stronger than UVA rays.
  • Ultraviolet C rays (short-wave radiation) never reach the earth's surface because the atmosphere filters them out.

UV rays can get through clouds, fog and haze. Water, sand, concrete and especially snow can reflect, and even increase, the sun's rays. We are exposed to more UV rays as the protective layer of ozone around the earth becomes thinner due to the effects of pollution and chemicals. The main source of UV radiation is the sun, but indoor tanning equipment, such as tanning beds and sun lamps, are also sources.

You have a higher risk of skin cancer if you:

  • have light-coloured skin, eyes or hair
  • work, play or exercise in the sun for long periods of time
  • had several blistering sunburns as a child
  • take drugs that make you more sensitive to UV light
  • use indoor tanning

UV index

The UV Index is a useful tool when it comes to sun protection. It tells you the strength of the sun's daily UV rays - the higher the number, the stronger the sun's rays and the more important it is to protect yourself.

UV Index and exposure table


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