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Prevention Strategies


The sun's rays are strongest between the hours of 10:00 a.m. and 4:00 p.m. Try to avoid these peak sunlight hours when planning your day. Think about scheduling outdoor activities in the morning and early-evening hours when the sun's rays are less intense and less likely to damage your skin. Did you know that swimming is best after 4:00 because it is usually warmer but with less intense sunlight?

Use the UV Index to Plan Your Day

The UV Index was developed by the National Weather Service and the Environmental Protection Agency (EPA). It provides a forecast of the expected risk of overexposure to UV rays and indicates the degree of caution you should take when outdoors. It predicts exposure levels on a 0 to 11+ scale. Experts recommend using sun protection when the UV Index is 3 (moderate) or higher.1

Check the UV index to minimize your UV exposure during peak UV times. It is available on the EPA website and printed on the weather page of many newspapers.

Understanding the UV Index

2 or Less

Low danger from the sun's UV rays for the average person

  • Wear sunglasses on bright days.
  • If you burn easily, cover up and use sunscreen.
  • Remember that water and sand can reflect the sun's rays and take precautions if you will be around reflective surfaces.
3 to 5

Moderate risk of harm from unprotected sun exposure

  • Take precautions such as covering up if you will be outside.
  • Stay in the shade near midday when the sun is strongest.
6 to 7

High risk from unprotected sun exposure

  • Apply a sunscreen of at least SPF 15.
  • Wear a wide-brim hat, sunglasses, and cover up clothing.
  • Reduce time in the sun between 10am and 4pm.
8 to 10
Very High

Very high risk of harm from unprotected sun exposure

  • Minimize sun exposure during midday hours (10am-4pm).
  • Wear sunscreen with an SPF of 15 or higher, wear sunscreen, sunglasses, and protective clothing, and seek shade.
11 +

Extreme risk of harm from unprotected sun exposure

  • Avoid sun exposure during midday hours (10am-4pm).
  • Apply sunscreen with at least SPF 15 liberally every 2 hours.
  • Seek shade, cover up, and wear a hat and sunglasses!

1: UV, Vitamin D and Health Key Messages. North American Conference on UV, Vitamin D and Health. March 8, 2006.