Large trucks are more numerous on the road today than in years past — and they’re traveling more miles than ever. The Federal Motor Carrier Administration reported a 49 percent increase in registered large trucks and a 76 percent increase in miles traveled by large truck from 1986 to 2006.

Large trucks are involved in thousands of accidents each year — many of them fatal. Florida had 4,566 vehicles involved in fatal crashes in 2007 and 288 involved large trucks, according to the National Highway Traffic Safety Administration.

What is behind these truck accidents? National studies show many are caused by negligence on the part of the truck driver.

According to a 2007 federal study of fatal truck accidents, factors that are frequently found in truck crashes include driving too fast for conditions, fatigue, roadway problems, feeling under pressure from motor carriers, adverse weather and brake problems. Truck drivers were cited as driving too fast almost 50 percent more often than passenger vehicle drivers in the accidents. And brake problems were cited for almost 40 percent of the trucks involved, the Fleet Motor Carrier Administration study reported.