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UV Radiation Information

Health effect and protective measures against UV radiation

Myths about protection against UV radiation

Some common misconceptions about UV radiation and the proper ways of protection:

Darker sunglasses offer more protection from UV radiation.

The most important thing to look for in sunglasses is how much UV radiation they filter out. It should be noted that there is no relationship between the colour of sunglasses and their UV filtering action. For adequate protection, one should wear sunglasses that are able to block at least 98% of the UV radiation.

You can't get sunburnt on a cloudy day.

Up to 80% of solar UV radiation can penetrate thin cloud cover. There are also occasions when broken clouds enhance UV radiation by reflection from their sides. In case of doubt, it is advisable to check the latest UV index through radio, television, the Observatory's website and Dial-a-Weather system (1878200).

You can't get sunburnt while in the water.

Water offers only minimal protection from UV radiation and reflections from water can enhance your UV radiation exposure. At half a metre under water, the UV radiation level is still 40% as intense as at the surface.

Sunscreens protect me so I can sunbathe much longer.

Sunscreen lotion should not be used to increase sun exposure time but to increase protection during unavoidable exposure. The protection provided by sunscreen lotion depends critically on their correct application. For more about sunscreen lotion and sunburn protection, please check out "Sunburn and SPF".

If you take regular breaks during sunbathing you won't get sunburnt.

UV radiation exposure is cumulative. The total health damage you get will be the sum of the effect of individual exposure. Therefore, to protect yourself the objective is to reduce the cumulative UV radiation exposure. This could decrease the chance of skin cancer.

If you don't feel the hot rays of the sun you won't get sunburnt.

Sunburn is caused by UV radiation which cannot be felt. The heating effect is caused by the sun's infrared radiation and not by UV radiation. Therefore, even if you don't feel the warmth, you may also get sunburn.

"Global Solar UV Index: A Practical Guide" , World Health Organization, 2002

Department of Health
For more health information related to UV, please visit the webpage of the Central Health Education Unit of the Department of Health.








Last revision date: <27 Dec 2012>