IT'S something that we can't feel or see but it's causing real damage and the risk is extreme.
During the recent heatwave the Ultraviolet Index in the Clarence Valley has been at the extreme end of the scale, at more than five times the safe limit of UV exposure.
Cancer Council NSW skin cancer prevention manager Liz King said UV radiation, rather than heat, wind or sunlight, is the cause of sunburn and can't be seen or felt.
"Almost all skin cancers are caused by overexposure to UV radiation from the sun," Ms King said.
UV radiation is made up of UVA and UVB rays which are able to penetrate the skin and cause permanent damage to the cells below.
"UVA penetrates deeply into the skin causing damage to cells' DNA, photo-ageing like wrinkling and blotchiness and immune-suppression.
"UVB penetrates into the top layer of the skin causing damage to the cells. UVB is responsible for sunburn, a significant risk factor for skin cancer, especially melanoma.
"Both UVA and UVB radiation contribute to sunburn, skin aging, eye damage and melanoma and other skin cancers."
The Cancer Council recommends that sun protection be used when UV levels are above three.
During the recent heatwave, and for the rest of the week, the UV Index reached as high as 16 across the Clarence Valley.
"When outdoors at times when UV levels three and above, Cancer Council NSW recommends using the five sun protective measures by slipping on long sleeved clothes, slopping on sunscreen, slapping on a broad-brimmed hat, sliding on sunglasses and seeking shade," Ms King said.
"Never rely on sunscreen alone.
"By using a combination of sun protection measures you can reduce your risk of getting sunburnt."