UV Index Scale and Colors

US UV Index scale


The UV Index scale used in the United States conforms with international guidelines for UVI reporting established by the World Health Organization. uviscaleh lg


AQI Numbers AQI Descriptor AQI Color
Low: 0 - 2 Low danger from UV rays for the average person. green
Moderate : 3 - 5 Moderate risk form unprotected sun exposure. yellow
High : 6 -7 Hi risk of harm from unprotected sun exposure. orange
Very High : 8 - 10 Very high risk of harm from unprotected sun exposure. Take extra precautions! red
Extreme : 11 - + Exreme risk of harm to your health. Take ALL precautions, skin and eyes can burn in minutes. purple

The shadow rule

One easy way to tell how much UV exposure you are getting is to look for your shadow.

  • If your shadow is taller than you are, your UV exposure is likely (no guarantee) low.
  • A short shadow means you are being exposed to higher levels of UV radiation. Seek shadow and protect your skin and eyes.

Learn more by visiting the offical US EPA website