UV Index Scale: The Strength of the Sun—Say "No" to Sunburns!
Sun Safety: How Long Does it Take to Burn?
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Body
The Sun is strong enough to damage skin and cause sunburn. Check out the UV index scale, which tells you how fast your skin will burn without protection, and find the latest UV forecast for your area.
What Is the UV Index?
The ultraviolet (UV) index is a scale representing the intensity of UV radiation the sun produces. The index was initially created by Canadian scientists in the early 1990s and has since been adapted worldwide. The UV Index also recommends “Actions to Take”—such as wearing sunscreen and a hat—to avoid getting burned.
UV Index Forecast
The U.S. National Weather Service (NWS) and the Environmental Protection Agency (EPA) measure ultraviolet levels daily and use these numbers to create daily exposure forecasts. See the UV Index forecast for your area by entering your zip code below (the information will open in a new tab) or visiting the EPA website.
UV Index Scale
Each UV Index Number is associated with “Exposure Level,” “Time to Burn,” and “Actions to Take.” People with lighter skin need to be more cautious. People with darker skin may be able to tolerate more exposure. Note that reflections off of snow, water, and white sand can nearly double UV strength.
UV Index Scale| UV Index Number | Exposure Level | Time to Burn | Actions to Take |
|---|
| 0 | Low | 60 minutes | Apply SPF 30+ sunscreen; wear sunglasses on bright days |
|---|
| 1 |
|---|
| 2 |
|---|
| 3 | Moderate | 45 minutes | Apply SPF 30+ sunscreen every 2 hours; wear a hat and sunglasses; seek shade during midday hours (10 a.m. to 4 p.m.), when the sun’s rays are most intense |
|---|
| 4 |
|---|
| 5 |
|---|
| 6 | High | 30 minutes | Apply SPF 30+ sunscreen every 2 hours; wear a wide-brimmed hat, sunglasses, and a long-sleeved shirt and pants if practical; seek shade during midday hours (10 a.m. to 4 p.m.), when the sun’s rays are most intense |
|---|
| 7 |
|---|
| 8 | Very High | 15-25 minutes | Apply SPF 30+ sunscreen every 2 hours; wear a wide-brimmed hat, sunglasses, and a long-sleeved shirt and pants if practical; seek shade during midday hours (10 a.m. to 4 p.m.), when the sun’s rays are most intense; limit time outdoors |
|---|
| 9 |
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| 10 |
|---|
| 11 or higher | Extreme | 10 minutes | Apply SPF 30+ sunscreen every 2 hours; wear a wide-brimmed hat, sunglasses, and a long-sleeved shirt and pants if practical; seek shade during midday hours (10 a.m. to 4 p.m.), when the sun’s rays are most intense; limit time outdoors |
|---|
Source: EPA UV Index
The Shadow Rule
Follow the EPA’s Shadow Rule to estimate how much UV radiation you are being exposed to:
- If your shadow is longer than you are tall, UV exposure is lower.
- If your shadow is shorter than you are tall, UV exposure is higher, and you should take necessary precautions.
Combating Sunburns
Sun safety is all about prevention. Wear broad-spectrum sunscreen whenever you are outside—no matter what the UV scale may say! If your fun in the Sun does result in sunburn, we hope that these 20 home remedies for sunburn will help provide relief.
Will it be sunny in your area this summer? Check out our Summer Weather Forecast to find out!
About The Author
Catherine Boeckmann
Catherine Boeckmann loves nature, stargazing, and gardening so it’s not surprising that she and The Old Farmer’s Almanac found each other. She leads digital content for the Almanac website, and is also a certified master gardener in the state of Indiana.
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