You must wear sunglasses to prevent damage to your eyes. While some contact lenses provide UV protection, they don't cover your whole eye, so you still need sunglasses. Look for sunglasses that protect you from 99 percent to 100 percent of both UVA and UVB light. This includes those labeled as "UV 400," which blocks all light rays with wavelengths up to 400 nanometers. Also, you may want to consider wraparound sunglasses to prevent harmful UV rays from entering around the frame.