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The Observatory enhances the Ultraviolet Index information service

The Observatory enhances the Ultraviolet Index information service
(17 July 2008)

An Ultraviolet (UV) Index of 11 or higher will trigger advisory messages from the Hong Kong Observatory about avoiding prolonged exposure to the sun and preventing eye and skin damage.

The advisory messages will be included in the Observatory's hourly weather report from today (July 17). This is an enhancement made by the Observatory on its UV Index service.

The Observatory has been measuring and disseminating UV levels since 1999. In 2006, it started to provide a daily 5pm forecast of the maximum UV Index for the next day. When the index is forecast to be 11 (corresponding to an extreme UV level) or above, the Observatory will, in the UV Index forecast bulletin, advise the public to avoid prolonged exposure under the sun. With the introduction of the new service, the Observatory will repeat in its hourly weather report the need to take protective measures whenever the measured index reaches 11 or above.

Senior Scientific Officer of the Observatory Mr Chan Chik-cheung said, "The Hong Kong Anti-Cancer Society recently pointed out the health effects caused by excessive UV radiation. The Observatory enhanced the information service on UV Index along this line. When the UV intensity reaches a high level (UV Index of 6 to 7), people should take precautions against UV. If the UV level goes up further, they should step up the protective measures."

Information on UV Index can be obtained through radio, television, the Dial-a-Weather system (1878200), the Observatory's website ( ) and Personal Digital Assistant (PDA) website ( ). For protective measures against UV, please visit the webpage of the Department of Health: .