What is UV?

Ultraviolet (UV) radiation is a type of energy produced by the sun and some artificial sources, such as solariums.

The sun’s ultraviolet (UV) radiation is the main cause of skin cancer. UV damage also causes sunburn, tanning, premature ageing and eye damage.

UV radiation isn’t like the sun’s light or heat, which we can see and feel. Your senses cannot detect UV radiation, so you won’t notice the damage until it has been done.

The UV Index

The World Health Organization's Global Solar UV Index measures UV levels on a scale from 0 (Low) to 11+ (Extreme). Sun protection is recommended when UV levels are 3 (Moderate) or higher.

The UV level is affected by a number of factors including the time of day, time of year, cloud cover, altitude, how close you are to the equator, scattering and reflection.

Sun protection times

The sun protection times show when UV levels are forecast to be 3 or higher.

You can find the sun protection times for your location on the free SunSmart app , on the SunSmart widget or at the Bureau of Meteorology website .

During the sun protection times remember to protect your skin and eyes by using covering clothing, sunscreen, a hat, shade and sunglasses. Don’t just wait for hot and sunny weather.

Health effects of too much UV radiation

Too much UV radiation can cause skin and eye damage, sunburn, tanning and skin cancer .

Some UV exposure is recommended for vitamin D.


Sunburn is a UV radiation burn to the skin. In Victoria's summer months, skin can burn in as little as 11 minutes and can take days or weeks to heal. Mild sunburn can be treated at home, but you should see a doctor immediately for severe and/or blistered burns. Find out more about sunburn treatment at Better Health Channel.

While the signs of a sunburn fade with time, the damage can’t be undone and adds to your lifetime tally of UV damage, which increases your risk of skin cancer.

Sunburn prevention is best. Always check the sun protection times on the free SunSmart app and use a combination of sun protection measures when required.

Eye damage

UV damage can cause photoconjunctivitis, which is also known as snow blindness or welders flash, photokeratitis, macular degeneration, cataracts, pterygiums and skin cancer of the conjunctiva and skin surrounding the eye.

Premature ageing

Up to 80% of fine lines and wrinkles are the result of UV damage. UV also causes skin sagging, blotchiness and roughness.


Photosensitivity is an abnormally high sensitivity of the skin or eyes to UV radiation. This means the skin can burn more easily, increasing your risk of skin cancer.

Photosensitivity is caused by ingesting, inhaling or coming into skin contact with photosensitisers – substances that cause photosensitivity. Photosensitisers include industrial chemicals, drugs, plants and some essential oils and fragrances. Some medications can cause photosensitivity. Check with your doctor or pharmacist, as alternate medication may be available.

Information on substances which cause photosensitivity can be found in the Guidance note for the protection of workers from ultraviolet radiation in sunlight from Safe Work Australia. 

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