UV index 10: how long until skin burns?
UV index 10 falls in WHO's Very high category. Without protection, very fair skin (type I) can start to redden in about 10 minutes, and olive skin (type IV) in about 30 minutes. These are rough estimates, not safe times.
Very high · 8–10 Extra protection: avoid midday sun; shade, shirt, hat, sunscreen are essential.
A warning, not a safe time. Redness shows up hours later.
Minutes to first redness by skin type
| Type IAlways burns, never tans; very pale skin, often freckles or red hair | about 10 minutes |
|---|---|
| Type IIUsually burns, tans with difficulty; fair skin, often light eyes | about 15 minutes |
| Type IIISometimes burns, tans gradually; light to light olive skin | about 20 minutes |
| Type IVRarely burns, tans easily; olive or light brown skin | about 30 minutes |
| Type VVery rarely burns, tans darkly; naturally brown skin | about 40 minutes |
| Type VIAlmost never burns; naturally dark brown to black skin | about 65 minutes |
What WHO advises at this level
WHO calls for extra protection. Avoid being outside during the midday hours where you can, and make sure you have shade when you are. A shirt, a broad-brimmed hat and sunscreen are a must, together with sunglasses. Unprotected fair skin can start to redden in about 10 to 15 minutes, and reflected UV can harm your eyes.
When and where you see this level
UV 10 is typical at summer midday in the subtropics, such as North Africa, the Middle East, the Canary Islands and the southern United States, and high in the Alps in summer. Tropical places reach it even in their cooler season.
What this means if you want a tan
At UV 10 fair skin can start to redden in about 10 minutes and olive skin in about half an hour. Sunbathing to tan here is a fast route to sunburn. Keep longer outdoor time for the early morning or late afternoon.
Frequently asked questions
How long does it take to burn at UV 10?
Rough estimates for unprotected skin at UV 10: type I: about 10 minutes; type II: about 15 minutes; type III: about 20 minutes; type IV: about 30 minutes. Redness usually appears hours later, and some people burn sooner. These are not safe times.
Is UV 10 high?
Very high (8–10). WHO calls for extra protection. Avoid being outside during the midday hours where you can, and make sure you have shade when you are. A shirt, a broad-brimmed hat and sunscreen are a must, together with sunglasses. Unprotected fair skin can start to redden in about 10 to 15 minutes, and reflected UV can harm your eyes.
Can you tan at UV 10?
At UV 10 fair skin can start to redden in about 10 minutes and olive skin in about half an hour. Sunbathing to tan here is a fast route to sunburn. Keep longer outdoor time for the early morning or late afternoon.
Sources
- WHO, WMO, UNEP, ICNIRP (2002): Global Solar UV Index – A Practical Guide
- WHO (2022): Radiation – The ultraviolet (UV) index, questions and answers
- ICNIRP with ILO and WHO (2007): Protecting Workers from Ultraviolet Radiation (skin types and SED, Table 1)
- Journal of Cosmetic Dermatology: Fitzpatrick skin phototypes with typical minimal erythema dose (Table 1, after Fitzpatrick 1988 and Pathak 1987)
- CIE: Standard Erythema Dose, a Review (1 SED = 100 J/m²)