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Potential Safety Benefits of Motor Carrier Operational Efficiencies (2011)

Chapter: Chapter Five - Conclusions and Further Research

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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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Suggested Citation:"Chapter Five - Conclusions and Further Research." National Academies of Sciences, Engineering, and Medicine. 2011. Potential Safety Benefits of Motor Carrier Operational Efficiencies. Washington, DC: The National Academies Press. doi: 10.17226/14612.
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51 This report has gathered research, vendor, survey, and inter- view data on commercial motor vehicle (CMV) transport risk avoidance strategies; that is, ways in which motor carriers can conduct their operations and deploy their assets to minimize crash risk. In this context, risk avoidance can be distinguished, at least conceptually, from conventional risk reduction. Risk reduction, constituting the majority of carrier safety efforts, improves the safety performance of individual “assets”— that is, drivers and vehicles. Risk reduction usually involves making company investments in proven interventions, such as improved driver selection, training, management oversight, or vehicle safety equipment. These actions are often evaluated based on their benefits per unit of cost. As defined here, risk avoidance strategies may also be conceptualized as carrier efficiencies with potential benefits to safety. This is an easier and more inclusive way to define these approaches; hence the report title Safety Effects of Car- rier Efficiencies. The following specific carrier practices and operational issues were discussed: • Employing preventive maintenance (PM); • Reducing empty (“deadhead”) trips; • Minimizing loading, unloading, and related delays; • Optimizing routing and navigation: – Providing navigational and routing aids; – Assigning familiar routes to drivers; • Selecting road type: divided versus undivided roads; • Avoiding work zones; • Avoiding traffic; • Emphasizing efficient scheduling: optimal times for safe travel; • Avoiding adverse weather; • Using higher-productivity vehicles (HPVs); • Using onboard computers and mobile communications; • Maximizing team driving; • Using electronic onboard recorders (EOBRs); • Optimizing fuel economy and safety: – Using speed limiters; – Monitoring driver fuel economy; and • Monitoring vehicle condition. These practices have in common that they are potentially time- or cost-saving practices with concurrent safety effects, mostly benefits, of interest. Secondly, they are pre-trip or pre-crash threat interventions. They are deployment, operational, or driving-route selection practices that potentially affect expo- sure to crash threats rather than improve direct responses to crash threats. Many of the individual strategies may appear to have the potential to reduce carrier crash rates by just a few percentage points. Concurrently adopting multiple strategies, however, could result in significant carrier crash reductions. Considering these strategies is an attempt to broaden the scope of commercial vehicle crash analysis and prevention. This expanded perspective seeks to expand motor carrier safety management to include safety-proactive operational planning. SAFETY-RELEVANT CARRIER EFFICIENCIES Chapter two of this report presented the 15 categories of carrier efficiencies, along with a general conceptualization of how these strategies work in crash reduction. The Haddon Matrix provides a general conceptual structure for identifying factors that influence crashes and outcomes. It divides the crash scenario in terms of time frame (i.e., pre-crash, crash, and post-crash) and in terms of the primary “actors” affecting the event (human, vehicle, and roadway and environment). For motor carrier safety, expansion of the Haddon Matrix is warranted to allow for both a broader time frame and more prominent “actors.” Expansion of the pre-crash time frame into pre-trip, pre-threat, and pre-crash impact facilitates con- sideration of carrier efficiencies and other strategies that avoid risk before that risk is confronted directly. Vehicle mechanical deficiencies are not among the top proximal causes of commercial vehicle crashes, but they are strongly associated with crash risk. Vehicle PM is reliably practiced and strongly supported by safety-conscious carriers and managers. Of practices presented in the current safety- manager survey, PM was both the most frequently used and the most strongly supported for safety. Most respondents also used maintenance management software and supported its use. These products provide many specific useful applications. One of the simplest ways to improve safety through improved efficiency is to reduce empty backhaul trips (“dead- heads”). Reducing empty miles is primarily motivated by its financial benefits, but there is also a proportional safety benefit. Every empty mile avoided reduces crash risk without reducing productivity and revenues. For-hire carrier empty miles have averaged about 20% of their total travel in recent years, but many efficient carriers are using web-based load boards and other means to reduce their empty miles to as low CHAPTER FIVE CONCLUSIONS AND FURTHER RESEARCH

as 10%. Reducing empty miles does not necessarily reduce carrier crash rate per vehicle-miles traveled, but does reduce crash rate per unit of productivity, ultimately a more com- pelling metric. As with empty miles, lost time owing to truck loading and unloading delays is a form of asset underutilization. Such time delays are more insidious, however, as they are more likely to affect driving performance. Drivers are generally unable to use waiting times for sleep or other restorative rest. Hours spent waiting but awake contribute to driver fatigue later, on the road. Schedule pressure or frustration may cause drivers to speed or otherwise hasten their work unwisely. Whereas system-wide technological changes may reduce the problem, the principal carrier countermeasure is to charge detention fees to customers for excessive delays (usually those more than 2 hours). Charging detention fees appears to help, but does not eliminate the problem. Smoother routing and navigation improve the efficiency of CMV operations. Each time a truck accrues unnecessary miles (or unnecessarily risks miles) because of poor routing, its equipment is not being utilized efficiently and risk has not been minimized. Drivers also perform more safely when they know or can easily follow their routes. A distinction can be made between routing and navigation in CMV operations. Routing optimization generally refers to improvements in the efficiency of the overall delivery operation. Navigation aids are devices to help drivers make a particular point-A-to- point-B trip. Most responding carriers used or encourage use of global positioning system navigation systems by drivers. The use of truck-specific routing and navigation systems was recommended by many. These systems help truck drivers avoid low underpasses and other large-truck hazards and restrictions. These systems offer many more features in sup- port of trip management. A simple, non-technological way to improve both efficiency and safety is to assign drivers familiar routes when possible. The safety advantages of divided over undivided highways are well known to highway engineers and safety researchers. Depending on the metric and study, undivided roads have two to five times the risk of divided roads. Survey results indicate that responding safety managers also appreciated the safety of Interstates and other divided, limited-access roads over undivided roads. Most responding companies encouraged the use of toll roads by providing drivers with toll transponders (e.g., EZ Pass) or fully reimbursing tolls. This prevents driver diversion from toll roads onto smaller, higher-risk roads. Highway work zones are very-high-risk areas for all vehicles, especially large trucks. Crash threats in work zones include constricted lanes, narrow or absent shoul- ders, makeshift signs, and traffic backups where light vehi- cles may dart in front of trucks to move up in the queue. Large-truck naturalistic driving research, whereby the loca- tions of incidents can be compared with randomly selected 52 exposure points, suggests an almost tenfold increase in risk in work zones. Thirteen percent of all truck crash involve- ments in the Large-Truck Crash Causation Study (LTCC) occurred in work zones, a percentage far above mileage expo- sure in work zones. Avoiding work zones was recognized by survey respondents as an important safety strategy. In recent decades, all across the United States, traffic delay has increased in urban areas, whether relatively small, medium-sized, or large. The recession of recent years has caused only a slight and temporary dip in urban traffic. In larger urban areas, free traffic flow occurs reliably only between 9:00 p.m. and 5:00 a.m. Predictable and signifi- cant congestion lasts for about 3 hours during both morn- ing and evening peak hours. Increases in traffic density and travel times generate disproportionate increases in interac- tions among vehicles and associated crash risk. Large-truck naturalistic driving data suggest that driving in heavy traffic involves six times more risk than driving in lighter traffic. About 45% of combination-unit truck (CT) driving and 57% of single-unit truck (ST) driving takes place in urban areas, and trucks in the LTCCS were more likely to be at-fault in multivehicle crashes in urban than in rural areas. Both safety- manager and other-expert survey respondents recognized the safety value of avoiding urban traffic. A new Freight Perfor- mance Measures service available from the American Trans- portation Research Institute and FHWA provides extensive and detailed travel time data to allow carriers to adjust their operations toward faster Interstate highway freight lanes and faster times for travel. Routing and navigation software ven- dors are making progress in incorporating traffic avoidance into their programs. Given the strong effects of traffic density on crash risk, one would think that off-peak driving, particularly night driving when traffic densities are lowest, would always be safest. Opposing this idea is the concept that driver fatigue is great- est in overnight hours, particularly in early morning, between 3:00 a.m. and 6:00 a.m. The overall time-of-day distribution of large truck crashes, available exposure data, and naturalis- tic driving studies suggest that day driving is more risky than night driving because of the presence of other vehicles. How- ever, overnight driving clearly is more risky from the stand- point of driver alertness and asleep-at-the-wheel risk. In this project’s surveys, both groups of respondents generally considered day driving to be safer than night driving. One conclusion consistent with all research reviewed is that the evening hours between 6:00 p.m. and 2:00 a.m. are probably among the lowest-risk travel times for large trucks. Given the disparity of research findings and opinions regarding other times of the day, however, conclusive research on the issue is needed. Reliable guidance on the question likely could reduce significantly the risk exposures of companies with time-of- day flexibility in their operations. Adverse weather is an obvious source of risk in driving and, when extreme, can be a direct crash cause. In the LTCCS, 14%

53 of truck crash involvements had weather as an associated fac- tor, but less than 1% of truck at-fault crashes were assigned a weather-related Critical Reason (proximal cause). In other words, bad weather contributes to many truck crashes, but is the proximal cause of only a few. In this project’s surveys, the factor “weather and roadway surface conditions” was consid- ered less important than enduring driver traits, temporary driver states, and roadway characteristics and traffic condi- tions (e.g., road type). Only the factor “vehicle characteristics” was rated as less important. These survey results are consistent with research findings. The question of truck size and crash risk is much like the question of time-of-day and crash risk. Differences of opin- ion abound, but it is difficult to draw reliable conclusions based on available research. Larger trucks might be safer if using them results in fewer trucks on the road and, therefore, less exposure to risk. Smaller trucks might be safer if they are individually less likely to figure in crashes or if their crashes are less severe because of their smaller size. In a current analysis based on several data sources, CTs and STs were found to have about the same total crash costs per mile trav- eled. This replicates a finding of a previous study by Wang in 1999. However, one cannot base operational decisions on this finding, because the uses and road type exposures of CTs and STs are different. Two major Canadian studies suggest that HPVs can be operated with equal or lower crash rates than one-trailer CTs. However, average crash severity of HPVs may be much higher than that of CTs, which perhaps cancels out their potential safety benefits. Project survey findings somewhat favor the use of larger trucks, but there are many contrary views as well. Commercial vehicle onboard computers and mobile com- munications (also known as telematics) cover a wide range of potential applications for operations and safety. Many of these applications are beyond the scope of this report. The report discussion focused on those specific telematic appli- cations mentioned by motor carriers in project surveys and interviews that relate to both operational efficiency and safety. These were discussed primarily with regard to safety benefits, though some concerns were expressed about safety losses owing to driver distraction. Onboard computer and communications suites are becoming complex and compre- hensive fleet monitoring and management tools. Systems allow central, real-time viewing of a vehicle’s map location, moving speed, engine speed, battery and fuel status, and trip history. Vehicle component (e.g., brake, tire) condition mon- itoring is also available. Systems can be programmed to flag any trouble indicator, whether it relates to vehicle function- ing or driver behavior. A safety concern arises, though, with regard to driver use of onboard systems during driving. Some carriers program their onboard systems to withhold visual displays from drivers when vehicles are moving. Four topics were added to the study based on comments by carrier safety managers on project surveys and interviews for the case studies. The four topics are team driving, EOBRs, fuel economy and safety, and vehicle condition monitoring. Brief discussions of each were provided. Team driving is an efficiency practice because a long-haul, team-driven truck can legally be moving almost continuously during an extended trip. Team driving has several important safety advantages. Most notably, the presence of another person in a vehicle reduces unsafe driver practices, including the tendency to continue to drive even when excessively drowsy. The major disadvantage of team driving is that sleep in a moving vehi- cle is usually lighter and less restorative. Still, a naturalistic driving comparison of team and solo driving found the inci- dent rate among team drivers to be less than one-half that of solo drivers. This report did not address regulatory or hours-of-service (HOS) compliance issues relating to EOBRs, but did touch on their safety management applications. EOBRs are used voluntarily by a growing number of CMV fleets, and they were cited as aids to both efficiency and safety by several interviewees. By automating driver log-keeping, EOBRs save drivers’ time, streamline records and compliance man- agement, and provide a means for safety oversight of drivers through quick identification of noncompliant drivers. EOBRs facilitate load assignments in larger fleets by identifying drivers with sufficient time available for the loads. Shackelford and Murray (2006) found other EOBR benefits to include improved fuel consumption monitoring and fuel tax compli- ance, quicker tabulation of driver mileage and loads, easier tracking of vehicle and engine wear, and better communica- tions and dispatching. The link between fuel economy and safety was noted by several interviewees, and is well established by research. Improved fuel economy is achieved in large part by changes in vehicle speed and driving style. These changes in turn produce safety benefits such as reduced driver stress, crash likelihood, and crash severity. Two primary approaches to improving fuel economy with concomitant safety benefits are speed- limiting vehicles and monitoring individual driver fuel con- sumption. CTBSSP Synthesis Report 16 examined the safety impact of large-truck speed limiters. In its project survey, most carrier respondents indicated that speed limiters were either “successful” or “very successful” in reducing crashes. Almost all of them believed that speed limiters had no nega- tive effects on their company’s safety and productivity. A more direct method for improving fuel economy is to monitor fuel use of individual drivers and trips. A capability for onboard fuel consumption monitoring is commonplace in today’s trucks. Almost all of the project case study companies mon- itor individual driver fuel use and component behaviors, such as hard braking and speeding. For example, Carrier J, a small charter bus company, uses onboard safety monitor- ing of driving behaviors and fuel use. The system generates a “Driver Report Card” for each trip. Driver acceptance of the monitoring has been good; they “make it a competition” to see who can earn the best scores.

Automatic monitoring of vehicle condition was cited by several case study interviewees as a growing application with both safety and efficiency benefits. Onboard monitoring of vehicle condition complements and extends the high-quality vehicle maintenance programs of many top fleets. Tire pres- sure monitoring exemplifies truck vehicle condition moni- toring. In the LTCCS, 1.1% of at-fault truck crashes were caused primarily by tire failure, which is usually the result of underinflated tires. A 2003 study of truck tire inflation by Kreeb et al. found that fleet maintenance of tires was often poor, resulting in high rates of tire underinflation. Improper inflation raised tire-related costs by $600 to $800 annually per tractor-trailer combination. About 5% of fleets currently use onboard tire pressure monitoring systems. A recent fleet test of tire pressure monitoring systems found their use to be associated with slower tire wear and 1.8% better fuel economy. What about the general relationship between efficiency and safety? Do the various efficiency practices add to greater safety? Do carrier practices that foster efficient operations also foster safe operations? The project did not measure either the efficiency or safety of any fleet, so it cannot provide defin- itive evidence. A survey question asked respondents about the general relationship. Strong majorities of both categories of respondents believed that, “Highly efficient carriers tend also to be more safe than other carriers.” Other studies suggest a positive relationship between systematic, high-performance company management and worker safety. This is especially true if company efficiency and growth can be achieved with- out putting excessive productivity and delivery pressure on drivers. Survey comments reinforced the notion of a positive relationship, with the same caveat about avoidance of exces- sive stress on drivers. By and large, the safety-manager and other-expert survey responses paralleled the findings of the literature review on various report topics. A top-level exception, however, was seen in the results of the opening survey questions on gen- eral factors affecting crash risk. In Questions 1 and 2 (for both safety managers and other experts), respondents were asked to select from the following the two factors with the greatest general effect on crash risk, and the one factor with the least effect: (a) Enduring driver traits; (b) Temporary driver states; (c) Vehicle characteristics and mechanical conditions; (d) Roadway characteristics and traffic conditions; and (e) Weather and roadway surface conditions. For safety managers, the vehicle-related choice (c) received the fewest “most” votes, whereas choice (d), “roadway char- acteristics and traffic conditions,” received the greatest num- ber of “least” votes. Thus, both (c) and (d) could be regarded as “losers.” Ironically, perhaps, choice (d) has the greatest relevance to the current study, because many operational transport efficiencies related to roadway and routing choices. 54 Empirical data (e.g., those related to divided and undivided highways and traffic density) demonstrate that the cate- gory (d) does affect crash risk strongly. For the other expert respondents, choice (d) was at the middle of the five factors with regard to its effects on crash risk. Most of the specific driving situations and operational prac- tices presented to both respondent groups received positive ratings for safety. “Maximizing travel on low-speed roads,” presented as the opposite of “maximizing travel on Interstates and other freeways,” received the highest negative ratings. Day driving was favored over night driving by both respon- dent groups, but with disagreement by some respondents. The two contrasting items on truck size generated the widest vari- ation of responses and disagreement. Although using “fewer, larger trucks” received slightly higher mean ratings by both groups, there was no consensus. PM was the most widely prac- ticed and rated carrier risk-avoidance practice. REPORTED EFFECTIVE CARRIER PRACTICES The project evidence and product review (chapter two), sur- veys (chapter three), and case studies (chapter four), as well as past reviews, indicate the following as common and bene- ficial carrier practices for consideration: • Operational planning and pre-trip actions (i.e., many of the strategies discussed herein) to reduce crash risk sys- tematically; • Pre-trip planning for individual trips, to include routes and schedules, including planned rest stops; • PM schedules and records for each vehicle, aided by maintenance management software; • Aggressively reducing empty backhaul trips for finan- cial benefits and to reduce unnecessary risk exposure; • Reducing loading and unloading delays by working with shippers and receivers and by changes in carrier operations; • Optimizing routing for individual vehicles and whole operations. Expedited travel through improved routing generally translates into safety gains as well; • Providing truck-specific navigational aids to drivers; • Assigning familiar routes to drivers when possible; • Routing vehicles through divided, limited-access roads (e.g., Interstates) when feasible, even at the expense of extra miles; • Avoiding highway work zones when feasible; • Avoiding urban areas when feasible, in particular dur- ing morning and evening peak hours; • Avoiding adverse weather and slippery road surfaces when feasible; • Using onboard computers and mobile communications for driver monitoring and to support operational effi- ciencies, but with measures to ensure that drivers are not distracted while driving; • Using speed limiters;

55 • Monitoring individual driver fuel economy and provid- ing feedback to drivers; • Using onboard tire pressure monitoring systems and other vehicle condition monitors as they become more available in vehicles; and • Generally, developing carrier efficiencies and disciplined operational practices that will support safety but will not create pressures on drivers or others to push delivery schedules or other activities to unsafe speeds. In addition to the established practices, this project has reported research, survey, and interview findings suggesting the potential value of the following for some carriers: • Charging detention fees to customers for excessive load- ing and unloading delays; • When operationally feasible and within HOS constraints, scheduling trips to include the evening hours between 6:00 p.m. and 2:00 a.m. if daytime traffic and associated inefficiencies and risks are concerns; • Using team drivers when feasible; • Using EOBRs for a variety of efficiency and safety man- agement benefits; • Equipping large trucks with automated transmissions to lessen driver workload and increase attention to driving; • Developing better and more detailed exposure statistics to use as denominators in safety evaluations. These might include vehicle-miles traveled, hours of driving (from HOS logs), trips, ton-miles, and revenue. Disaggregation of exposure by company depot, vehicle configuration, location and region, time-of-day, day-of-week, and other classifications would permit better safety assessments and shifting of operations toward lower risk conditions; and • Joining or forming a consortium of similar carriers who meet regularly to share information about improving safety and reducing losses. In such consortia, carriers can share techniques and procedures for improved oper- ational efficiency and safety. RESEARCH AND DEVELOPMENT NEEDS In 2008, 9,006,738 large trucks traveled 227.5 billion miles in the United States. The average per-vehicle annual mileage for CTs was 64,764 miles. In addition, 843,308 buses traveled 7.1 billion miles. Given all of these miles traveled and the asso- ciated exposure to risk, there would appear to be abundant opportunities for quantitative analyses of commercial vehicle travel patterns and other operations to identify efficiencies with safety benefits. Much of this research would elaborate on the findings reviewed previously and provide more compelling arguments for various carrier or industry operational changes. Other research would help to resolve specific unanswered questions about carrier operations and safety. Most transportation safety statistics are more meaningful and heuristic if they are derived in part from some exposure measure. Carrier exposure data include vehicle mileage, hours of driving, times of driving (i.e., times-of-day and days-of- week), geographic locations, freight lanes (corridors), types of runs, vehicle types, and many other “denominator” metrics. Much of crash-risk analysis consists of simple calculations of rates based on event (crash, incident, violation) numerators and exposure denominators. For example, a common rate cal- culated by carriers is crashes (e.g., police- or DOT-reported) per mile. Calculation of relative crash risks for different cate- gories of exposure is a more powerful risk analysis tool because it identifies higher- and lower-risk exposures within a com- pany’s operations. Relative crash risk is determined by the following formula: A simple example would be a carrier’s analysis of its crashes on different freight lanes or corridors (e.g., I-40, I-70, and I-80). If the carrier collected and classified both its crash and mileage data by freight lane, then it could determine rel- ative crash risks on those lanes. For large carriers, such analy- ses might provide statistically reliable guidance for reducing risk exposure. Some carriers interviewed for the case studies conduct extensive risk analyses, but the practice appears to be limited to large and progressive carriers. Carriers might benefit from more guidance and tools for collecting better internal exposure data and using that data in risk analysis. In an Australian study, Wright et al. (2005) identified the same need for quantitative safety and productivity analyses within fleets. The authors conducted in-depth surveys and interviews with managers at 12 motor carriers. All companies provided qualitative assessments of their safety programs and associated costs and benefits. Only a few companies, however, were able to provide even a limited amount of quantitative data, suggesting that rigorous safety program evaluation was lacking among Australian motor carriers. Two operational issues presented on project surveys gen- erated the widest variations in opinion. Research gaps were also seen in these areas. The first was day versus night driving. There would be many operational safety applications from better data and knowledge on CMV crash risks as a function of time of day. No one has determined whether night driving is generally more or less dangerous for CMVs than daytime driving. Yet, the answer is relevant to millions of truck dis- patch decisions made annually. Many assume that night driving is less safe than day driving because of the greatly elevated driver fatigue risk associated with the early morn- ing circadian valley, and because light-vehicle serious crash rates spike during the overnight hours owing to alcohol impairment and reckless driving. Yet, truck crash rates vary strongly with traffic density, and traffic densities are lowest at night. Large-truck naturalistic driving data suggest that night driving is less dangerous because there are fewer traffic interactions. The time-of-day distributions of truck crashes in the LTCCS and national crash databases suggest the same Relative Crash Risk Factor % in CrashesFa= ( ) ctor % in Normal Driving( )

(as reviewed in the section “Efficient Scheduling” in chapter two). However, both the safety-manager and other-expert surveys found majorities of respondents believing day driving to be safer. Systematic study could answer this question. Two potential approaches are time-of-day studies of crashes per unit of exposure for limited-access roadways (e.g., toll roads) and large-carrier–based studies in which both crashes and exposure are closely tracked company wide. Both types of studies could be enhanced by the use of additional numerators (e.g., tabulations of total crash harm in addition to crash counts) and control for roadway type. The second issue generating extremes of opinion was that of truck size and safety. The question whether HPVs are to be used more widely on the U.S. road system is both controver- sial and difficult to answer objectively. Although the issue has been discussed here in the context of operational efficiency and safety, HPVs are also problematic with regard to vehicle stability, pavement wear, and bridge weight capacity. Nev- ertheless, studies could compare freight movement produc- tivity (e.g., freight ton-miles and comparable freight volume metrics) with crash harm for different truck configurations, including STs, CTs, and HPVs. Different truck configurations may also be assessed with regard to fuel consumption and emissions per unit of freight movement. This project has presented evidence linking traffic conges- tion to crash risk, and also evidence of the safety benefits of transport route optimization and navigation aids. Navigation aid vendors are beginning to equip systems with real-time updates based on ambient traffic conditions. Real-time routing updating is a relatively new application that will see continued development and more widespread use in the coming years. Systems providing such real-time updates and adjustments pri- marily use global position system–equipped cell phone trans- missions as a source of data on traffic movements. The principal challenge is in analyzing such massive data in real time to produce reliable adjustments in routing guidance. The Intelligent Transportation Society of America has published a white paper entitled, “Smart Mobility for a 21st Century America: Strategies for Maximizing Technology to Minimize Congestion, Reduce Emissions, and Increase Effi- ciency.” The publication relates to motor vehicle and other modal transportation in general, rather than specifically to CMV transport. Nonetheless, its five broad innovation strate- gies apply also to CMV transport and to topics addressed in this report. The innovations include: • Making transportation systems more efficient; • Providing more travel options; • Providing travelers with better, more accurate, and more connected information; • Making pricing and payments more convenient and effi- cient; and • Reducing trips and traffic. 56 Many of the same evaluation criteria for in-vehicle safety technologies (e.g., collision warning systems) also apply to products and services intended to make operations more effi- cient. These decision factors are critical for making, using, and buying technologies in the CMV industry. They include: • Return on Investment for the Purchaser: Sustains com- mercial success of technologies purchased and used by carriers; • Initial Cost: Affects early deployment, because a high initial-purchase cost makes it difficult for a carrier to raise the needed capital to buy technologies; • Demonstrated Effectiveness to Improve Safety, Secu- rity, and Efficiency of Operations: Represents the major benefits that offset the costs of technologies; • System Reliability and Maintainability: Provides the results and usability of technologies for carriers and manufacturers (original equipment manufacturers and vendors); • Driver Acceptance: Ensures that drivers are receptive to technologies that are user-friendly and effective in improving safety and security; • Market Image: Involves using state-of-the-art technolo- gies to improve a carrier’s image by designating a com- pany as progressive and concerned about the safety and security of their drivers and loads; • Market Demand: Depends on awareness of the tech- nology, along with acceptance and belief in its value, which is particularly important to manufacturers intro- ducing a new product; • In-Cab Technology Interface Integration: Minimizes cost, distraction, and human errors while using the tech- nology; and • Liability: Influences carriers, drivers, and manufacturers, particularly relating to the data stored by certain tech- nologies and their use. Several of the operational practices in this report were addressed under the Motor Carrier Efficiency Study (MCES). The MCES Inefficiencies Report pointed out that a common thread running through many inefficiencies is delay resulting in large part from parties (e.g., customers) or forces (e.g., weather and traffic) external to carriers. The inefficiencies may be mitigated, however, by improving the quality, accu- racy, and timeliness of data available to transport operators. Thus, a research and development opportunity is to determine data needs, collection methods, analysis routines, and means of transmission to provide timely, operations-critical infor- mation to carriers and to drivers. Phase II of the MCES, in planning at this writing, will pilot test technological interventions to provide carriers with oper- ational information in areas such as the following, addressed in this report: • Reducing time waiting to be loaded or unloaded, or to access the facilities where these activities are done; • Reducing empty trips, particularly when interchanging loads between intermodal facilities;

57 • Reducing delays associated with congestion—particu- larly congestion associated with traffic incidents; and • Reducing fuel consumption, likely by providing motor carriers with means to better control truck speeds. Except in the area of preventive maintenance, this project did not specifically address carriers’ use of databases, spread- sheets, and other software for safety and operational manage- ment. This would be a detailed project in itself. Nevertheless, this is an area in which management efficiency is likely to have clear safety benefits. These safety benefits may be simi- lar to the benefits of maintenance management efficiency, except on a broader scale. Databases can enhance safety man- agement applications such as the following (most from Safe Road Systems 2010): • Creating custom driver scorecards; • Tracking CSA 2010 compliance by driver; • Managing DOT inspections; • Monitoring crash, incident, and violation statistics; • Scheduling drug tests; • Tracking HOS compliance; • Tracking OBSM data; • Tracking route experience; and • Monitoring driver license status and certifications. This report, previous CTBSSP reports, and other frequently cited studies of carrier safety management have been based primarily on successful, safer-than-average carriers. That is primarily because these carriers are active in national CMV transport organizations and conferences. They are more likely to be known to researchers and much more likely to be willing to participate in safety management studies. Studies of motor carriers with a wider range of safety performance records would strongly test safety management conclusions drawn in this and other studies based mainly on safety-conscious motor carriers and their officials. Such studies could be structured as case-control or parametric comparisons between carrier prac- tices and their safety performance criterion measures. Another research method applicable to validating risk- avoidance strategies is the intensive carrier case study. In 2009, Murray et al. conducted and published a 4-year occu- pational road safety case study of Wolseley, the world’s largest heating and plumbing distributor, based in the United Kingdom and operating in 28 countries. The comprehensive case study classified dozens of Wolseley safety interventions within an expanded Haddon Matrix and chronicled their implementation and safety outcomes over a 4-year period. The company reduced its crash rate by more than 40% over the period. It also reduced employee injuries, traffic and reg- ulatory violations, and financial losses. Although this holis- tic research approach does not isolate the effects of single interventions, it does “tell a complete story,” which other companies may choose to emulate.

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TRB’s Commercial Truck and Bus Safety Synthesis Program (CTBSSP) Synthesis 20: Potential Safety Benefits of Motor Carrier Operational Efficiencies addresses risk avoidance strategies and highlights their use and perceived safety effects. The report is designed to assist motor carriers in deploying their vehicles in ways that may minimize crash risk.

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