Alexandra pool first to test UV meter

By MONIQUE DEVEREUX

A public swimming pool in a small Otago town has become the first to test a new UV ray warning system, which experts hope will catch on nationwide.

The UV index is used internationally and was introduced in New Zealand to replace the burn-time system in place for the past 10 years.

The new index is already being used by the Herald to alert readers to the level of cancer-causing UV rays each day.

But in Alexandra a real-time display unit has been installed at the public swimming pool. The mechanism was designed and built by Niwa and tested for several months at their research centre in Lauder, just north of Alexandra.

The Lauder centre is one of five stations around the world involved in researching the causes of stratospheric ozone depletion.

One of the principal Lauder scientists, Dr Richard McKenzie, said that although the index system was new and would continue to need developments, it was a huge step forward.

The real-time display at the swimming pool looks similar to the Fire Service warnings for fire risk, but it adjusts automatically to show the level of UV rays present in the area.

The solar-powered meter measures ultra-violet radiation levels from 1 to 11+. At level one and two, for example, the UV level is low. Only low-level protection is needed and people can safely stay outside.

UV levels of eight to 10 are very high and people should seek shade between 11am and 4pm and cover up.

New Zealand's UV rate has increased by 15 per cent in the past 20 years. New Zealand now has the highest rate of melanoma and skin cancer in the world.

The UV level is different to the temperature, meaning severe sunburn can still occur even though it may be a cloudy or cool, windy day.

Which is why an accurate, up-to-the-minute display was useful, said Dr McKenzie.

Each device costs up to $3000, but comes with $500 worth of servicing by Niwa each year.

Dr McKenzie said the aim was to ensure the devices remained within the price range for sponsors such as Rotary or district councils.

The solar power system made the displays portable.

"And so you could actually use it in an event situation, like at a Stanley St tennis match or Eden Park. You could imagine having them at a school athletic sports day would be giving everyone useful information."