* Fallen cargo, wheel separations and other highway debris likely cause more than 25,000 crashes a year and on average kill between 80 and 90 people annually. Although these accidents make up less than 1 percent of all crashes in the United States and Canada, it is worthwhile examining whether they can be reduced.

* Poor tire maintenance, especially underinflation, is the largest cause of tire debris on U.S. and Canadian roads.

* Loads carried on short trips -- taking a Christmas tree or a new mattress home -- concern safety specialists, who say people are less likely to pay attention to securing the load if they are traveling a short distance.

* Most fatal crashes involving roadway debris occur during the daytime on major roads with a speed limit of 55 mph or higher. By contrast, about half of other fatal crashes happen at night on major roads where the speed limit is less than 55 mph.

* Heavy or medium trucks make up 9 percent of the vehicles involved in all fatal crashes, compared with 27 percent of vehicles involved in fatal debris- related crashes.

* About a quarter of the trucks that authorities stop for suspected safety violations are taken out of service or impounded for violations, many of them for underinflated or worn tires. Periodic vehicle safety inspections are mandatory for private and commercial vehicles.

* The rougher the pavement, the more likely it is that there will be a crash involving debris from a vehicle that has lost its load.

Source: AAA Foundation for Traffic Safety, "The Safety Impact of Vehicle-Related Road Debris," June 2004.