Exposure to Ultraviolet (UV) radiation is the driving force of skin cancer development. In Australia we have the highest rate of skin cancer in the world. We Aussies love the outdoors, but if we are going to be exposed to the elements, it is important to understand the UV index.
Recent research shows that most people have a poor understanding of how to interpret the UV index. People most often equate heat with UV radiation, however this is not a direct correlation, as on a cool cloudy day, the UV index may still be high.
The UV index was first developed in 1992 and later adopted by the World Health Organization as an international measure of UV intensity. Now available as part of the weather forecast, the UV index is a linear scale that measures the intensity of UV radiation that causes sunburn. For example, if a person with fair skin will get a sunburn in 40 minutes at a UV index of 4, then they can expect to get a sunburn in 20 minutes if the UV index is 8.
The above graph from the Australian Bureau of Meteorology shows the averages for Sydney year-round. Although the averages drop lower in winter, they may still be quite high during the day. To complicate this we have to balance our vitamin D intake and our personal risk factors for skin cancer.
Perhaps easier than getting out the calculator is downloading one of the clever and free apps available from the Cancer Council site.
The Cancer Council’s free SunSmart app is available via the Cancer Council website. The app will tell you:
- Sun protection times, including a personalised alert function
- Sunscreen calculator: based on your current clothing, height and weight
- 7 Day forecast
- Personalized vitamin D tracker
Since it is everyday sun exposure that leads to a majority of sun-damage, people may not realize that avoiding sunburn alone is not enough. A daily personal reminder to consider one’s UV exposure is a great way of reducing UV-associated skin cancers and aging.
Visit the Cancer Council website for more information and to download the SunSmart app:
Dr Margit Polcz
First Year Dermatology Registrar