Photokeratitis

Did you know that fresh snow is capable of reflecting 80% of UV light?

Those of you that were lucky enough to have a snow day today may have found that the light outside had a particular brightness about it today.

Even though in my neck of the woods it was overcast and the Sun stayed behind the clouds the light that did get through the clouds was reflected from the deep covering of water crystals lying in some places to a depth of nearly one foot.

This reflected UV light can cause real problems for people who are out in it for long enough without adequate protection. The electromagnetic radiation can cause damage to cornea and the conjunctiva, parts of the front of the eye. Effectively these parts of the eye get sunburnt and like sunburn in other parts of the body it isn't noticed until after the damage has been done. This leads to snow blindness a form of photokeratitis.

http://cf6.ahm.com.au/images/95/aug_snow.jpg

The symptoms of snow blindness include watering eyes, small constricted pupils and twitching eyelids. It feels to the sufferer that they have sand in their eyes.

As with other sunburn type injuries healing can be rapid if the source of the snow blindness is removed. Getting out of the snow, sitting in a darkened room and wearing sunglasses or tinted snow googles will all help the healing process.

Of course not having a snow day would help.

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