The most important things to pay attention to when purchasing a pair of sunglasses for skiing are UV Protection, the types of lenses, durability, and peripheral vision.
First of all, make sure that the sunglasses provide at least 95% protection from both UVA and UVB rays, as long-term exposure can cause permanent damage to your eyes.
Secondly, choose sunglasses that are specifically designed for use during the winter. This means that you should look for an anti-fog feature, because fogging can sometimes cause sunglasses to crack, taking away any quality protection you had. Fogging can also cause temporary blindness, which can be fatal when skiing at fast speeds.
Thirdly, polycarbonate lenses may be the most expensive, but they will far out perform and outlast cheaper lenses. Polycarbonate lenses offer the best UV protection in addition to being shatterproof. You will not regret investing in these lenses. Also, make sure to look for tints that will provide the best clarity and contrast, as well as glare reduction. Rose, yellow, or orange tints are effective for this.
Lastly, pay attention to peripheral vision. Try to find wide, wraparound lenses that will give you a 180-degree view of the slope. Eagle eye sunglass technology, designed by NASA engineers, are the most effective for peripheral vision. Revo sunglasses are known for utilizing this technology.