ultra-violet radiation

UV radiation is often divided into three sub-sections - UV A, UV B and UV C. The earth's atmosphere blocks UV C radiation and all but a small amount of UV B, so the ultra-violet radiation at the earth's surface is mostly UV A and UV B. UV B is the most harmful for humans.

There are many important reasons to be aware of the UV radiation at the earth's surface:

• The risk of skin cancer grows with every sunburn.
  
• Protecting the skin during the first 18 years of life is likely to reduce the risk of skin cancer by more than 50 per cent.
  
• Doctors associate eye cataracts with UV exposure.
  
• You can sunburn even on cloudy days. In some cases, UV radiation can penetrate clouds, mist and fog.
  
• Staying in the shade does not provide complete protection. A lot of UV radiation does come directly from the sun, but some also bounces around as it is scattered by the atmosphere.
  
• Sunburn is not connected with the sensation of heat. You can still get serious sunburn in winter, despite feeling cold.
  
• Fresh snow reflects up to 80 per cent of the sun's rays. Snow, water and concrete "mirrors" significantly increase sunburn. Skiing enthusiasts should be particularly careful to protect their eyes and skin.