UV radiation causes the skin to make more of a pigment called melanin to protect itself. This causes the skin to change colour. When there is more radiation than your skin’s melanin can cope with, you get a sunburn. You can be exposed to UV radiation from the sun and also from a solarium (tanning bed). It's also possible to get sunburn while swimming or in the snow. This is usually caused by the sunlight reflecting off the snow, ice or water and burning your skin. You are most at risk of sunburn if you have fair skin. But all people can get sunburn, including people with dark skin.