What is UV radiation?
UV is difficult to understand because you can’t see it or feel it – it is not connected to sunshine or heat.
Our sun emits different kinds of energy:
- Infrared red radiation that we can feel (heat or temperature)
- Visible light that we can see (sunlight)
- UV radiation (that can’t be seen or felt)
There are three types of UV radiation:
- UVA: transmits freely through the earth’s atmosphere.
- UVB: about 15% of UVB transmits through to the earth’s atmosphere. The rest is absorbed by ozone.
- UVC: is absorbed by ozone and does not reach the earth’s surface.
UVA and UVB both contribute to skin cancer, sunburn, skin ageing and eye damage.
Exposure to UV radiation is the main factor that causes skin cells to become cancer cells. Almost all skin cancers (approximately 99% of non-melanoma skin cancers and 95% of melanoma) are caused by over exposure to UV radiation. The simplest way to reduce your risk of skin cancers is to use sun protection when the sun’s rays are strong enough to damage your skin and in NSW, this is most days of the year.
UV Index – An internationally standardised open ended numerical scale developed by the World Health Organization that measures the amount of UV radiation reaching the earth’s surface. It begins at zero and has no upper limit. The UV Index is often represented as a number line with accompanying action statements and descriptive words which convey UV intensity. – from CCWA UV website.