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41 their small size may enable them to improve their safety practices more quickly and dramatically following a CR. Truck Vehicle-Based Safety Technologies Improved Brakes (e.g., air disc brakes) An alternative explanation for the pre- versus post-CR Electronic Stability Control differences, however, is that the effect reflects, at least in Roll Stability Control part, a statistical artifact called regression to the mean. In Forward Collision Warning Systems statistics, regression toward the mean is the phenomenon Side-Object Detection Systems that, if a variable is extreme on its first measurement, it will Backing Collision Warning Systems tend to be closer to the average on its second measurement Lane Departure Warning Systems (Everitt 2002). Regression to the mean is greatest when Onboard Safety Monitoring measurement-to-measurement correlations are lowest. This Driver Alertness Monitoring would be the case for year-to-year crash likelihoods for EOBRs Electronic Data Recorders smaller carriers, because their crashes are fewer and thus Vehicle Condition Monitoring (e.g., tire pressure moni- inherently more subject to larger random variations. Larger toring systems) carrier crash likelihoods vary less year-to-year because they Automated Transmissions tend to "average out" more each year. Because the study Speed Limiters contained no control groups (i.e., carriers "deserving" CRs Truck-Specific Navigation Aids but randomly selected to not receive one), it is impossible Enhanced Trailer Conspicuity to rule out regression to the mean as an alternative explana- Enhanced Trailer Rear Lighting/Warnings tion for the observed stronger CR effects for smaller carri- Video Mirrors. ers in this study. Source: Knipling and Hyten (2010). The DOT Volpe Center published a Compliance Review Effectiveness Model with similar findings (Volpe National Transportation Systems Center 2008). It used a comparison inclusive of all crash consequences) to be approximately five group of all carriers not receiving a CR to control for global times those of straight trucks, light trucks/vans, passenger year-to-year changes in crash likelihood, but like the vehicle- cars, and motorcycles. miles traveled study did not use a control group consisting of carriers meeting safety performance criteria for receiving a High average life-cycle crash costs mean that tractorsemi- CR but not actually receiving one. trailers, among all major vehicle types, are generally the best platform for cost-effective applications of vehicle-based safety technologies. A safety device installed on a truck tractor at the VEHICLE EQUIPMENT AND MAINTENANCE time of purchase will generally perform for the life of the vehi- Onboard Safety Technologies cle and have far greater opportunities to prevent a serious crash than the same device installed on a car, short-haul truck, or Numerous vehicle-based technologies are applicable to large other low mileage vehicle. Moreover, approximately two- truck safety and especially to the safety of long-haul trucks, thirds of all human and material harm in large truck crashes is which are usually tractorsemitrailers. The textbox lists var- outside the truck (i.e., to other motorists), so there is high ious safety technologies available for installation on large potential for large liability claims against truck drivers and trucks. Tractorsemitrailers are in many ways the ideal plat- their companies. A company that can afford to equip its vehi- form for the use of advanced crash avoidance technologies. cles with proven safety technologies is likely to reap positive Although their crash rates per mile traveled are the lowest of returns-on-investments (ROIs) over time. Table 16 shows esti- major vehicle types, their high mileage exposures (510 mated median ROIs and median payback periods for fleets times the average car) and high severity of their crashes (on adopting three of the better-known, vehicle-based crash avoid- average approximately twice that of cars) make them inher- ance devices (FMCSA 2009). ently high-risk vehicles (Wang et al. 1999; Knipling 2009). Zaloshnja and Miller (2007) calculated the average compre- The previous discussion suggests that all CMV transport hensive cost of a police-reported crash involving a large companies consider equipping their vehicles with crash avoid- truck to be $91,112 in 2005 dollars. This included direct eco- ance technologies, and that they would profit from the nomic loss plus a monetary valuation of pain and suffering investment. Unfortunately, there are economic obstacles to and quality-of-life lost. In spite of tractorsemitrailers' gen- greater deployment of truck safety technologies (Houser erally low crash rate per vehicle-miles traveled, the combi- et al. 2007; Knipling 2010). Large, successful companies nation of their high mileage exposures and high severities of may have sufficient capital and cash flow to finance pur- crashes that occur drive up their average life-cycle crash chases of vehicle safety technologies. But that is not true of costs to levels far above those of other vehicles. One direct most companies, and especially smaller companies, where comparison (Wang et al. 1999) found tractorsemitrailer per- tight profit margins are the rule. In addition, larger companies vehicle life-cycle costs (all crashes regardless of fault and are more likely to be able to negotiate price reductions based

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42 TABLE 16 ESTIMATED BENEFIT-COSTS OF THREE LARGE TRUCK SAFETY TECHNOLOGIES Vehicle-Based Median ROI Median Safety Technology per $1.00 Investment Payback Period Forward Collision Warning $4.28 23 Months Lane Departure Warning $3.96 23 Months Roll Stability Control $5.51 18 Months Source: FMCSA (2009). on volume purchases, and are more likely to have technicians Vehicle Maintenance Practices on payroll who can support system use. A recent Transport Topics article by Johnson (2011) noted the problems small Proper vehicle maintenance is an essential legal requirement companies have keeping their equipment current. The article for CMV safety, and most carriers regard vehicle mainte- quoted Andy Ahern of Ahern and Associates, a consulting nance as their most fundamental safety activity (Knipling firm, to the affect that "The small guys are having a hard et al. 2003). Both federal and state governments have exten- time. They're not getting paid on time, they're not getting the sive vehicle regulations and enforcement programs targeting financing to buy equipment and many of them cannot get brakes, tires, lights, and other vehicle components with their rates up." potential deficiencies. Mechanical failures are rare as a direct cause of crashes when compared with human causes, but Vehicle safety equipment was addressed by several sur- they are still considerable. In the Large Truck Crash Causa- vey questions. Question 23 asked about EOBR use. Only 16 tion Study (LTCCS), 10% of truck at-fault involvements of 110 respondents reported using EOBRs on their vehicles. (5.5% of all truck crash involvements) were attributed to a Those using them gave them a high average effectiveness vehicle-related Critical Reason (proximal cause). Types of rating of 3.4 on the 04 Likert scale. Question 25 asked failures included brake deficiencies, cargo shifts, tire/wheel respondents if they "Purchase[d] advanced vehicle safety failures, and suspension failures. The presence of a vehicle systems (forward collision warning, lane departure warning, problem as an associated factor (even when not necessarily a electronic stability control, onboard computers to monitor cause) was strongly correlated to crash fault (i.e., Critical driving, etc.)." Only 4 of 111 respondents answered yes. In Reason assignment). Associated vehicle factors were noted Question 31 on the most important areas of safety manage- in 62% of truck single-vehicle crashes, 50% of truck at-fault ment, the choice "vehicle safety equipment (e.g., technolo- multi-vehicle crashes, but only 21% of truck not-at-fault gies such as collision avoidance systems)" received the multi-vehicle crashes (Knipling 2009). The nature of the fewest votes of the ten areas presented. vehicle deficiency can be associated with crash type. Blower (2009) reported that brake OOS violations were more com- The following are survey comments relating to vehicle mon in LTCCS crashes where the truck was the striking vehi- safety equipment: cle, whereas lighting OOS violations were more common when the truck was the struck vehicle. Vehicle maintenance Vehicle safety equipment is more often than not too is one of the seven CSA BASICs. Earlier in this chapter it costly for small carriers to obtain in today's economy. was noted that small carrier vehicle OOS rates in inspections The continual adding of expensive [equipment and] are greater than 20%, with the important caveat that these cost to new motorcoaches is pricing a new coach at an inspections target poor-performing carriers and thus are not impossible level for many small companies. Thus, older random samples. vehicles will be used much longer. We would love to try EOBR's, but do not have the bud- Motor carriers of all sizes consider vehicle maintenance to get. Funding these safety advances will be critical to be a priority safety management activity. Regular practices smaller operators. include pre- and post-trip inspections, annual vehicle inspec- tions, PM, and repairs. Small companies perform many Few of the case study interviewees expressed an active maintenance tasks themselves, although some do not have interest in vehicle safety technologies. Carrier C, which hauls facilities for major repairs. In CTBSSP Synthesis 1 (Knipling large 8-axle trailers, expressed an interest in trailer disc brakes et al. 2003), respondents were asked to rate and rank 28 car- for improved performance. Tire Pressure Monitoring Sys- rier safety management practices for their importance. tems were also mentioned in interviews. Some carriers con- "Regularly scheduled vehicle inspection and maintenance" sidered these technologies to be a "wish list" item, but cash received the highest mean rating of all 28 practices. In a sur- flow problems eliminated them from serious consideration. vey of 148 safe carriers, Corsi and Barnard (2003) found that More often, safety technologies were not mentioned by inter- 76% agreed or strongly agreed with the statement, "Cost is viewees. no issue when it comes to keeping our vehicles defect free."