The ultraviolet index is an international standard measurement to measure the strength of ultraviolet (UV) radiation that reaches the earths surface.
How much UV radiation reaches the Earth depends on many factors including ozone depletion, seasonal and weather variations. Thanks to the EPA, the UV Index is available wherever you are, and we display your realtime UV Level for your location within the Reapply app. Download the app here.
When the index is less than 2, it’s the lowest risk of sun damage but can still sunburn after 60 minutes. When the UV Index is at a moderate level of 3 to 5 without sun protection, you will burn approximately 30 to 45 minutes. Even on cloudy days, you should apply a broad-spectrum sunscreen of 30 or higher every two hours.
If the UV Index reaches 6 or above you should reduce the amount of time you spend in the sun between the hours of 10 a.m. and 4 p.m. The time to burn can vary by skin type, but at a high UV level, it is approximately 15 to 25 minutes.
The sun is at its highest in the sky at noon when the sun’s rays have the shortest distance to travel through the atmosphere, and UV levels are at their highest. Early morning and late afternoon, the sun’s rays travel a greater distance through the atmosphere, and the intensity of UV levels are a lot less.