Cover Image

Not for Sale



View/Hide Left Panel
Click for next page ( 14


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 13
13 riers loading at their own facilities and for those delivering to respondents, the proportion was 23 of 27. The safety effec- their own stores or other facilities (Delcan Corporation 2007b). tiveness of the practice was given a mean rating by users of 3.4 on a 1-to-5 Likert scale. Several interviewees for case According to carriers reporting to the MCES and those studies used detention fees. One interviewee considered them interviewed for the current study, shippers and receivers may effective, but added that "aggressive" enforcement and col- be relatively indifferent to the costs incurred by carriers and lection was essential for reducing excessive delays and their drivers while waiting. Further, shippers' and receivers' own negative safety consequences. Another lamented that the efficiency may actually benefit from practices that create practice was not highly effective because the fees became a steady truck queues while their own operations proceed on corporate-to-corporate billing issue, rather than a penalty felt schedule without workload spikes or interruptions. Gate reser- directly by frontline depot supervisors with the most influence vation and appointment systems could alleviate the problem, on the problem. although carriers reporting to the MCES argued that their use was geared toward optimizing facility efficiency rather than The following are two safety-manager survey comments reducing truck waiting times. relating to loading and unloading delays: One corporate vice president for safety interviewed for Inefficiencies of shippers/receivers in the loading and the study believed that carrier use of EOBRs had an indirect unloading process has the most negative effect on safety benefit of reducing loading and unloading delays. That is for our drivers. because EOBRs reinforce the notion that HOS compliance is Our biggest challenge is with our customers and suppli- nonnegotiable, and also because they provide more com- ers. There is an ignorance or apathy towards an efficient pelling documentation of delivery schedule disruptions caused loading or unloading process. by excessive dock delays. The MCES (Delcan Corporation 2007b) suggested a wire- OPTIMIZING ROUTING AND NAVIGATION less communications application concept called Virtual Queu- Smoother routing and navigation improve the efficiency of ing as a logistical and technological intervention to reduce CMV operations. The following quotation from the MCES excessive loading and unloading delays. Virtual queuing literature review report (Delcan Corporation 2007a) summa- would extend queues to trucks reaching the vicinity of the rizes the importance of optimized routing for operational terminal. It would allow consignees to monitor and dynam- efficiency: "Each time a truck accrues additional miles due to ically reschedule dock operations to compensate for delays less than optimal routing, the equipment is not being utilized in both truck arrivals and departures from the facility. to its full potential, and it does not complete its intended mis- sion in the least possible time, with the least possible costs On project surveys, respondents were asked to rate the in labor, equipment wear, and fuel." Improved routing effi- safety benefits of "reducing loading and unloading delays" ciency appears to aid safety as well. There are two primary on a seven-point Likert scale ranging from -3 ("Reduces safety rationales for aiding routing and navigation. The first Fleet Safety") to +3 ("Improves Fleet Safety"). Among safety is avoiding exposure, especially to higher-risk roads, that is, managers, the overall mean rating was +1.8. Among other- roads likely to be congested with traffic or otherwise haz- expert respondents, the mean rating was +1.4. For both groups, ardous. The second is easing drivers' navigation workloads. these were among the highest mean ratings for driving situa- Making navigation easier for drivers reduces distraction and tions and practices presented. associated crash risk. This section explores these benefits and describes products aiding CMV routing and navigation. Several of the case study carriers assign dedicated routes to successful, experienced drivers. These assignments are A distinction can be made between routing and naviga- coveted. In addition to keeping drivers on familiar roads, tion in CMV operations (Bennett 2009). Routing optimization dedicated runs provide a stable income, predictable home generally refers to improvements in the efficiency of an over- times, and more regular work-rest cycles. all pickup-and-delivery sequence, as in a full driver tour- of-duty or multiday trip. Routing optimization can also be For carriers, the most obvious and feasible means to reduce applied to a whole fleet or company. Navigation aids more excessive delays is to charge a fee to shippers and receivers often refer to devices to assist drivers in making a particular for excessive wait times. These detention fees are written into point-A-to-point-B trip. shipping contracts, with 2 hours appearing to be the most common threshold for fees. Affected drivers may receive all or most of the money charged. Safety-manager respondents Providing Routing and Navigational were asked whether they charged detention fees to customers Aids to Drivers for excessive loading and unloading delays. The question was omitted from bus operator forms. Among all responding Portable and vehicle-installed Global Position System (GPS) carriers, 34 of 50 charged detention fees. Among TL carrier devices are marketed as aids to navigation and mobility, not

OCR for page 13
14 as safety devices. Yet the proper use of automated GPS nav- Intermodal rail versus truck routing and cost compar- igation aids by commercial drivers supports safety by the two isons; mechanisms mentioned earlier: reduction of risk exposure Customized routing by specification of preferences or and easing driver mental workload. With regard to risk expo- routes to be avoided; sure, reductions can simply be in the quantity of exposure Manual override of specified routing; (i.e., reducing mileage for the same productivity) and in "Location radius" tool to search for points of interest exposure to higher-risk road conditions. within specified distances of any location; Geofencing (restriction of vehicles within or outside of Truck-specific navigation aids can steer drivers clear of specified zones); roads where truck traffic or hazardous cargo is restricted or Driver rest stop options in compliance with HOS rules; prohibited. They can warn drivers of low-clearance under- Identification of weigh stations along routes; passes (e.g., bridges with less than 14 ft of vertical clearance, Identification of intermodal rail ramps; the national standard for local roads and collectors), low- Automation of fuel and mileage tax tracking; weight-bearing bridges, or other hazardous locations. Sys- Integration with communications systems for real-time tems can route drivers around higher-risk roads, such as management; undivided roads and those with high traffic densities. If sys- Web access to routing and navigation functionality; tems are updated, they can route drivers around work zones Data downloads to spreadsheets or other programs; and or road closures. The relative risks associated with some of (Being developed) Dynamic adjustments based on real- these road types and conditions will be documented in the time assessments of traffic and weather conditions. following sections. Systems can also route trucks to avoid toll roads, although this diversion practice is more likely to Potential GPS benefits touted by vendors include better be detrimental to safety, as toll roads generally have safer real-time dispatching, increased productivity, improved HOS design features than do non-toll alternate routes (Short 2006). compliance, decreased overtime, lower fuel use, improved customer service, validation-of-service calls, lower insurance Any system that routes trucks away from higher-risk roads costs, and decreased driver speeding. One deficiency of and toward lower-risk roads reduces overall crash risk inde- most truck-specific navigation systems is that they route to pendently of driver and vehicle risk factors. Truck-specific an address, not to a delivery entrance. For large delivery loca- road information is needed, however. Leone (2010) reports tions, this means that drivers may still be at a loss to pinpoint the experience of trucking company Transport America, two their exact destination. Manual "last-mile" directions are still of whose trucks were involved in bridge underride crashes needed (Leone 2010). Another, more significant concern is in the preceding year. In one case, the driver was following that different vendors may gather their own highway data a paper map, and in the other, the driver was following a themselves or through independent contacts with state and general-purpose navigation device. Neither driver was aware local agencies. There is little standardization across different that the route included low-clearance underpasses. The safety vendors and products. manager interviewed for Case Study D (Large Truckload Carrier) told of similar mishaps related to truck drivers using In an article on route optimization benefits, Bennett (2009) general-purpose navigation aids. A bill proposed (though not quotes Ken Snow, president of Hagopian Cleaning Services, under immediate consideration) in New York state would out- on the company's successful use of route optimization soft- law commercial drivers from using general-purpose GPS units ware. The company's fleet consists of 27 vans used for carpet (Leone 2010). and upholstery cleaning. Snow estimates that route optimiza- tion reduces company mileage by 5% to 10%, or 25,000 to Multiple vendors provide truck-specific routing and navi- 50,000 annual miles. This is reduced exposure to crash risk. gation aids. Major communications providers can offer inte- Route optimization also provided fuel savings and the elimi- grated, truck-specific navigation systems with their systems. nation of the manual task of route planning for the trucks. Each Specific features and services of truck-specific routing and evening, the company runs the route optimization program navigation aids may include: to plan the next day's routes. Onboard GPS units would aid drivers in A-to-B trips, but would not optimize the sequences U.S.- and Canada-wide street-level map data with turn- of multiple stops of a truck or multiple trucks of a fleet. Larger by-turn directions; companies with multiple fleet locations can network the appli- Routing in accordance with height restrictions, low- cation to optimize regional coverage. A vendor interviewed for weight bridges, seasonal road closures, and so forth; the article claimed that companies with as few as four vehicles Best "practical" versus shortest routing choices; could benefit from route optimization software. For mobile Optimized stop sequences; maintenance or other service operations, trips back to a central Truck-specific toll costs; depot can be reviewed to determine whether they could have Fuel optimization for cost and in accordance with com- been avoided by better provisioning of the vehicle before its pany purchase plans; departure. Another company representative interviewed for Hazardous materials and larger-truck-size routing; the article reported the results of a company survey of drivers

OCR for page 13
15 using a routing and navigation aid system. The survey found Situation awareness is the ability to "effectively filter that 85% of company drivers believed the system helped them information in a data-rich environment," or simply "knowing every day to travel more efficiently and with less stress. what is going on" (Shinar 2007). The primary task of driving includes controlling the vehicle and responding to traffic On project surveys, respondents were asked to rate the events. Any secondary task such as navigation can reduce safety benefits of using routing and navigation aids on a performance on the primary task. seven-point Likert scale ranging from -3 ("Reduces Fleet Safety") to +3 ("Improves Fleet Safety"). The item was LTCCS statistics showed a relation between truck drivers' stated as, "Increase routing efficiency using GPS navigation roadway familiarity and crash involvement. The LTCCS had aids and/or truck routing software." Among safety managers, no mileage exposure database or non-crash control data set, only one respondent out of 77 assigned the practice a nega- so relative rates of crash involvement cannot be discerned. tive rating, and the overall mean rating was +1.8. Among One can, however, use LTCCS data to discern associations other experts, there were no negative ratings among 31 between roadway familiarity and fault in crashes, with the respondents and the mean rating was +1.1. assumption that a higher incidence of fault also implies higher risk. Figure 3 shows three categories of LTCCS truck crash With regard to carrier practices, 42 of 76 respondents said involvements and, for each, the percent of truck drivers who their drivers use general-purpose GPS systems, and 29 of 77 were unfamiliar with the road. That is, they had never or only used truck-specific systems. There was considerable overlap rarely driven the road before. Overall, 26% of LTCCS drivers among the users of the two types, suggesting that in many were unfamiliar with the roads on which they crashed. When fleets some drivers use general systems, whereas others use crash involvements were disaggregated by driver unfamil- truck-specific systems. iarity with the roadway, one sees a strong relationship with crash fault and type of crash involvement. Assigning Familiar Routes to Drivers On project surveys, respondents were asked to rate the safety benefits of assigning familiar routes to drivers when Driving involves three types or levels of performance and possible. As with similar questions, respondents were pre- skill: controlling the vehicle, responding to driving events sented with a seven-point Likert scale ranging from -3 (e.g., other traffic, signs, and signals), and navigation. Exces- ("Reduces Fleet Safety") to +3 ("Improves Fleet Safety"). sive attention to any one of these levels can interfere with The overall mean for safety manager-respondents was +1.7. performance on the others. For example, novice drivers are Among other experts, the mean rating was +1.6. typically preoccupied with controlling the vehicle, to the detri- ment of their ability to respond to traffic events (Shinar 2007). Beyond roadway familiarity, are there other strategies Similarly, excessive attention to navigation can reduce atten- managers and dispatchers could use in assigning routes to tion to basic vehicle control and, in particular, traffic events. drivers? One prudent strategy is to assign more difficult and Think about your own driving on roads that you drive every risky routes to more experienced and competent drivers. Or, day, compared with your driving on unfamiliar roads. For stated another way, avoid the situation in which an inexperi- experienced drivers on familiar roads, both vehicle control and enced or otherwise questionable driver is exposed to higher- navigation are automatic. One can anticipate and attend closely risk traffic or roadway conditions. Knipling (2009) presented to traffic conditions and specific threats. On unfamiliar roads, a hypothetical mathematical model suggesting that this strat- drivers are not as able to anticipate specific roadway and traf- egy would reduce overall fleet crash risk because it would fic risks. This is particularly true when drivers are looking for reduce the dangerous convergence of the weakest drivers with a specific turn or destination. the most hazardous roadway situations. The model assumed a % Rarely or Never Drove Road 38% 40% 35% 29% 30% 25% 17% 20% 15% 10% 5% 0% Single-Vehicle Crash MV Truck At-Fault MV Truck Not At-Fault Truck Crash Involvement Category FIGURE 3 Road unfamiliarity and crash involvement.