Snow blindness

Snow blindness is a painful condition caused by exposure of unprotected eyes to sunlight reflected from snow. This is especially a problem at high altitude and polar regions.

The problem is also related to the condition arc eye sometimes experienced by welders.

Some guidelines to use when choosing a good trekking/mountaineering pair of sunglasses:

• 99-100% UV absorption
• Polycarbonate or CR-39 lens (lighter, more comfortable than glass)
• 5-10% visible light transmittance
• Large lenses that fit close to the face
• Wraparound or side-shielded to prevent incidental light exposure

See also

• Winter sport