Debris in the roadway

Road debris, a form of road hazard, is debris on or off a road. Road debris includes substances, materials, and objects that are foreign to the normal roadway environment. Debris may be produced by vehicular or nonvehicular sources, but in all cases it is considered litter, a form of solid waste. Debris may tend to collect in areas where vehicles do not drive, such as on the edges (shoulder), around traffic islands, and junctions.

Road spray or tire kickup is road debris (usually liquid water) that has been kicked up, pushed out, or sprayed out from a tire. In 2004, a AAA Foundation for Traffic Safety study revealed that vehicle-related road debris caused 25,000 accidents and nearly 100 deaths a year.

Road debris can be caused by various factors, including objects falling off vehicles or natural disasters and weather, specifically wind, storms, tornadoes, hurricanes, etc.

Examples of road debris include:

Road debris is a hazard that can cause loss of vehicle control with damages ranging from a flat tire, vehicular rollover, penetration of the passenger compartment by the debris, or collision, with accompanying injuries or deaths. In the year 2011, the National Highway Traffic Safety Administration's Traffic Safety Facts found that more than 800 persons were killed across America by "non-fixed objects" (a term that includes roadway debris). California had the highest number of total deaths for any state, while New Mexico had the greatest probability for death from a vehicle-debris crash in that year.

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