The Australian Radiation Protection and Nuclear Safety agency now produces live tracking displays for the nine largest Australian cities. ( See links in table below ) While these were set up to help people protect against skin cancers, they can also be used as a proxy measurement for the total amount of potentially damaging and discomforting solar radiation present at any time, and allow extremely photosensitive patients to better control their symptoms and discomfort by reference to a readily available radiation measurment.

The UV Index is a meausure of the amount of UV present. When the UV index is 3, or above, Vitamin D is synthesised in the skin. In addition people with severe photosensitivity can experience considerable discomfort at UV levels below these levels.

Trying to guess the UV level by simply looking out the window is not just difficult, it is essentially impossible. As well as distance from the equator, the time of the day and the time of the year, atmospheric conditions, particularly humidity levels at both ground level and above, greatly influence the UV index. A particularly bright day in Hobart can have higher levels of UV at mid-day than the same day of the year with simlar amount of cloud cover in Brisbane , if Brisbane's humidity levels at ground level and in the upper atmosphere are higher than those in Hobart. Even a seemingly overcast mid Summer day in Hobart, can, if the humidity levels are sufficiently low eneough, generate near extreme levels of UV.

The live tracking display can help you plan your day around both expected levels of the UV index and also to check on actual level at any time of they day. If you live some distance from these major cities the figures given will only be a rough guide, because of local humidity, cloud and rain conditions.