How to use the UV Index


Photo: © Mevans, istock.com, 2004.

The higher the index, the stronger the sun, and the greater the need to take precautions

What to do when the Index is between 0 and 2?

UV isn't usually a problem. But be careful when it's bright and there's snow on the ground. Fresh white snow can reflect over 80% of the UV from the sun, meaning you are receiving almost twice as much UV. Special UV sunglasses will help to protect your eyes.


Photo: © istock.com, 2004.

What to do when the Index is between 3 and 7?

Take care. Wear big hats and clothes that cover your skin. Put sunscreen on skin that you can't cover. Don't be fooled if it's cool or slightly cloudy. The UV still gets through.

What to do when the index is 8 or more?

Look out! Don't stay too long in the sun, especially between 11 a.m. and 3 p.m. Wear your sunglasses (the special UV ones) and stay in the shade. Put on more sunscreen every 2 hours or after swimming or working up a good sweat. Be especially careful when you're down south on winter holidays. On clear, sunny days in the tropics, the UV Index is normally between 11 and 14.

 

UV Index values and sun protection: Detailed table

The table below outlines the sun protection actions recommended at different levels of the UV Index: 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.

UV Index sun protection
UV IndexDescriptionSun protection actions
0 - 2Low
  • Minimal sun protection required for normal activity.
  • Wear sunglasses on bright days. If outside for more than one hour, cover up and use sunscreen.
  • Reflection off snow can nearly double UV strength, so wear sunglasses and apply sunscreen on your face.
3 - 5Moderate
  • Take precaution by covering up, and wearing a hat, sunglasses and sunscreen, especially if you will be outside for 30 minutes or more.
  • Look for shade near midday when the sun is strongest.
6 - 7High
  • Protection required - UVdamages the skin and can cause sunburn.
  • Reduce time in the sun between 11 a.m. and 3 p.m. and take full precaution by seeking shade, covering up exposed skin, wearing a hat and sunglasses, and applying sunscreen.
8 - 10Very High
  • Extra precaution required - unprotected skin will be damaged and can burn quickly.
  • Avoid the sun between 11 a.m. and 3 p.m. and seek shade, cover up, and wear a hat, sunglasses and sunscreen.
11+Extreme
  • Values of 11 or more are very rare in Canada. However, the UV Index can reach 14 or higher in the tropics and southern U.S.
  • Take full precaution. Unprotected skin will be damaged and can burn in minutes. Avoid the sun between 11 a.m. and 3 p.m., cover up, and wear a hat, sunglasses and sunscreen.
  • Don’t forget that white sand and other bright surfaces reflect UV and increase UV exposure.
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