Click for next page ( 6


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 5
6 CHAPTER TWO RESULTS OF LITERATURE REVIEW The objectives of the literature review include: involving large trucks result in the occupant(s) of the other vehicle being killed (Traffic Safety Facts 2003 2004). Because Addressing truck safety with an emphasis on the role of of the higher mileage-related crash exposure of trucks and speed, the higher relative crash costs associated with large truck col- Examining the asserted benefits and issues associated lisions, there is a premium on making trucks, and truck drivers, with speed limiters, as safe as possible. Annual average crash costs are more than Reviewing policy initiatives relating to speed limiters four times greater for a tractor-trailer ($88,483 in 2000 dollars) mandates, than for a passenger car (Wang et al. 1999; Zaloshnja and Highlighting key industry policy positions, and Miller 2004). Analyzing the effectiveness of speed limiters in terms of published studies and industry surveys. Speed and Crashes SPEED AND CRASHES The relationship between increased speed and crashes has been well documented (Stuster et al. 1998), with the key cor- Background relation being speed and crash severity. Excessive speeding by drivers decreases a driver's response time in an event and may In 2006, 385,000 large trucks (gross vehicle weight greater increase risk as a result of speed-related increases in crash than 10,000 lb) were involved in traffic crashes in the United exposure. As cited by NHTSA in Traffic Safety Facts 2003: States; 4,932 of these crashes involved a fatality. Within this "Speeding reduces a driver's ability to steer safely around population, a total of 4,995 people died and an additional curves or objects in the roadway, extends the distance neces- 106,000 people were injured. Large trucks account for 3% of sary to stop a vehicle, and increases the distance a vehicle trav- all registered vehicles, 8% of total vehicle miles traveled, 8% els while the driver reacts to a dangerous situation" (2005, p. 1). of all vehicles involved in fatal crashes, and 4% of all vehicles Impact force during a vehicle crash varies with the square of involved in injury and property-damage-only crashes. One the vehicle speed; therefore, even small increases in speed out of eight traffic fatalities in 2006 resulted from a collision have large and lethal effects on the force at impact (Roads and involving a large truck (2006 Traffic Safety Facts 2008). Traffic Authority 2005). The FMCSA (2005 Large Truck Crash Overview 2007) reported that "speeding" (exceeding These statistics should be put in perspective, relative to the the speed limit or driving too fast for conditions) was a factor overall safety performance of truck drivers. Although the sta- in 22% of the fatal large truck crashes. The recently completed tistical data does not provide a definitive answer on the relative Large Truck Crash Causation Study estimated that 22.9% of safety impact of CMVs and the role of truck driver responsi- all large truck crashes and 10.4% of large truck/passenger car bility in crashes, several analyses concluded that the majority crashes could be coded as traveling too fast for conditions of truck drivers are safe, with a minority of truck drivers being (Report to Congress . . . 2006). responsible for a disproportionate number of safety violations and crashes (Hickman et al. 2005). Independent of these data, The risk associated with vehicle speed is illustrated by the there is a public perception that the trucking industry is not as estimated annual savings of 2,000 to 4,000 lives as a result of safe as it should be. The data that can be analyzed indicate that the nationwide reduction in the highway speed limit to 55 mph truck drivers have lower crash rates per million vehicle miles in 1974 (Waller 1987). When the national speed limit was later traveled than light vehicle drivers (Traffic Safety Facts 2003 raised to 65 mph, the occurrence of vehicle crashes showed a 2004). Nonetheless, light vehicles are extremely vulnerable marked increase (Evans 1991). A recent analysis by Patterson when they interact with trucks because trucks often weigh et al. (2002) of the repeal of the National Maximum Speed 20 to 30 times as much as light vehicles (Insurance Institute Limit in 1996 supported Evan's (1991) data. Patterson et al. for Highway Safety 2002) and trucks require 20% to 40% (2002) found that 23 states had raised their rural Interstate more stopping distance than do light vehicles (Heavy Truck speed limits to 70 or 75 mph and modeled the number of vehic- Safety Study 1987). This is best illustrated by the statistic that ular fatalities on rural Interstates from 1991 to 1999 against the more than three-fourths of multiple-vehicle fatal crashes new speed limits in these states (e.g., 75 mph, 70 mph, or no