CE-certified boots for motorcycling have been tested against resistance to abrasion, penetration by sharp objects and lateral crushing. Goggles or helmet visor — Eye protection is of utmost importance - an insect or a kicked-up pebble in the eye at speed has enough momentum to cause significant damage. Such an event could easily cause the rider to lose control and crash. Besides this danger, squinting into the wind is unpleasant at best and watering eyes are quite distracting. Earplugs — Most riders experience substantial wind noise at speeds above . Earplugs help protect against hearing damage, and reduce fatigue during long rides. Vests — Made with high-visibility colors and retroreflective materials, vests can be worn over jackets to increase the chance of being seen and allow drivers to better judge the speed and position of riders, especially in adverse conditions of dark and wet. Motorcycle airbag vests – worn in jackets and vests can offer riders a neck brace and spine protection, as well as abdomen, chest, ribs, and hip/pelvic protection. Other PPE — Dirt bike riders wear a range of plastic armor to protect against injury from falling and hitting other riders and bikes, running into track barriers, and being hit by flying debris kicked up by the tires of other riders' bikes. This type of armor typically covers the back, chest, and sometimes the extremities. It is increasingly common for gloves, jackets, pants, and boots to be outfitted with hard plastics on probable contact areas in an effort to ensure that when a motorcyclist contacts the ground, his clothing will permit him to slide relatively easily as opposed to "crumpling", risking injury to body parts being stressed in abnormal directions. Riders sometimes use the acronyms MOTGMOTT and ATGATT, which stand for "Most Of The Gear Most Of The Time" and "All The Gear All The Time", when describing their personal gear preferences. Training In many developed countries riders are now either required or encouraged to attend safety classes in order to obtain a separate motorcycle driving license. Training can help to bridge the gap between a novice and experienced rider as well as improving the skills of a more experienced rider. Skills training would seem to be the answer to reducing the KSI ("killed or seriously injured") rate among motorcycle riders. However, research shows that some who undergo advanced skills training are more likely to be at a