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39 TABLE 13 choices (a) and (b) were regarded as having the greatest effect SAFETY-MANAGER RESPONDENTS' FLEET on crash risk, whereas vehicle-related choice (c) was regarded OPERATION TYPES as having the least. Choice (d) has the greatest overall rele- No. Safety vance to the current study, because many operational transport Operation Type Managers efficiencies are related to roadway and routing choices. Other (a) For hire: long haul/truckload 21 choices may also be relevant to specific operational practices. (b) For hire: long haul/less-than-truckload (LTL) 2 (c) For hire: local/short haul (most trips < 100 miles) 2 This respondent group considered temporary driver states (d) Private industry: long haul 6 (b) to be the strongest factor affecting crash risk. Roadway (e) Private industry: local/short haul (< 100 miles) 10 characteristics and traffic conditions, the choice most relevant to the current study, was third in the "most" voting and fourth (f) Passenger carrier: scheduled service 4 in the "least" voting. Thus, relative to safety managers, other (g) Passenger carrier: charter 15 experts considered choice (d) to be relatively more important. (g+h) Passenger carrier: both scheduled service and charter 10 (h) "Other" (mostly variations of above types) 3 Total (N): 73 Driving Situations and Operational Practices Possibly Affecting Fleet Safety Questions 3 to 18 were preceded by the following general were completed (24%). Survey results were tabulated by the instructions: reports program. The following are driving situations or carrier operational prac- tices which may reduce, not affect, or improve fleet safety. Assign OTHER-EXPERT SURVEY RESULTS each situation or practice a negative value if it decreases safety, zero if it does not affect safety, or a positive value if it improves Factors Affecting Safety and Crash Risk safety. Choose one number for each. Consecutive items may rep- resent alternative or even opposing safety strategies. Questions 1 and 2 addressed factors affecting safety and crash risk. The same five choices were presented in each. Question 1 A seven-point Likert rating scale was used for responses, asked for the respondent's choice of up to two factors hav- ranging from -3 (reduces fleet safety) through 0 (no effect on ing the greatest effect, whereas Question 2 asked for the one safety) to +3 (improves fleet safety). "X" was given as a factor with the least effect. Table 14 presents responses. As choice for "no opinion/not sure." Table 15 provides the 16 expected, choices for the two opposite questions (greatest items, the number of ratings for each of the eight choices and least) were more or less inversely related. Driver-related (-3, -2, -1, 0, +1, +2, +3, X), as well as the total number of TABLE 14 OTHER-EXPERT RESPONSES RELATING TO FACTORS AFFECTING SAFETY AND CRASH RISK (1) Factors Affecting Safety and Crash Risk: Consider the entire fleet of North American commercial vehicles (trucks and buses). Across all these drivers and vehicles, which factors have the greatest association with crash risk? Pick up to (1) (2) two of the factors below which, in your opinion, have the greatest association with Most Least crash risk. (2) In your opinion, which one factor has the least association with crash risk? (a) Enduring/long-term driver traits; e.g., age, physical abilities, medical 14 7 conditions, personality, behavioral history (b) Temporary driver states; e.g., moods, daily circadian rhythms, effects of recent sleep, effects of recent food & fluids, effects of environmental conditions in cab, 25 0 etc. (c) Vehicle characteristics (e.g., configuration, safety equipment, load) & 7 12 mechanical condition (e.g., brakes, tires) (d) Roadway characteristics & traffic conditions; e.g., undivided vs. divided 10 3 highways, construction zones, traffic density, speed limits, lane restrictions, etc. (e) Weather and roadway surface conditions; e.g., wet vs. dry, road surface 2 9 friction, visibility, wind, etc. Total Responses: 58 31

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40 TABLE 15 OTHER-EXPERT RATINGS OF DRIVING SITUATIONS AND OPERATIONAL PRACTICES Driving Situation/Operational Practice: -3 -2 -1 0 +1 +2 +3 N Md Avg. (3) Perform regular vehicle preventive 0 0 0 0 10 8 13 31 +2 +2.1 maintenance (4) Use brokers or other services to reduce 2 0 4 19 4 2 0 29 0 -0.1 empty backhauls (deadheads) (5) Reduce loading/unloading delays 0 2 0 2 15 5 7 31 +1 +1.4 (6) Increase routing efficiency using GPS navigation aids and/or truck routing software 0 0 0 7 18 3 3 31 +1 +1.1 and websites (7) Maximize travel on Interstates & other 0 0 0 2 12 9 8 31 +2 +1.7 freeways (8) Maximize travel on low-speed roads (e.g., 6 11 10 3 1 0 0 31 -2 -1.6 two-lane local roads) (9) Maximize day driving to avoid driver 0 1 1 5 11 11 2 31 +1 +1.2 fatigue & other nighttime risks (10) Maximize night driving to avoid 1 7 12 7 2 2 0 31 -1 -0.7 daytime traffic (11) Avoid urban rush hours and other heavy 0 0 3 4 14 5 5 31 +1 +1.2 traffic situations (12) Avoid adverse weather and slick roads 1 0 1 3 12 11 3 31 +1 +1.3 (13) Avoid construction zones 0 1 0 4 14 8 4 32 +1 +1.3 (14) Assign familiar routes to drivers when 0 0 0 2 13 10 6 31 +2 +1.6 possible (15) Use fewer, larger trucks (e.g., multi- 2 1 4 9 7 5 3 31 0 +0.4 trailer trucks) when possible (16) Use more, smaller trucks (e.g., single- 3 2 6 13 6 0 1 31 0 -0.3 unit trucks) when possible (17) Maximize use of driver teams for long 1 0 1 7 18 2 2 31 +1 +0.8 hauls (18) Monitor fuel economy for individual 0 0 1 12 13 4 1 31 +1 +0.7 drivers and provide feedback Grand Mean: +0.8 Avg. = Arithmetic average (mean); Md = Median (middle); N = Number of respondents. responses (N), the median (Md) and the arithmetic average the spread of answers for Questions 15 and 16 regarding truck (Avg.), also known as the mean. Median ratings are pro- size, indicating a wide range of opinions. vided along with mean ratings because of the large number of choices (seven), and because extreme choices might shift means unduly. Note also that Questions 17 (on driver teams) Additional Questions and 18 (on fuel economy monitoring) had no corresponding questions on the safety-manager version of the survey. Question 20 asked respondents about the general relation- ship between carrier efficiency and safety. Table 16 pre- The practices with the highest mean ratings for these respon- sents the question stem, response choices, and number for dents were preventive maintenance (item 3, +2.1), maximizing each. A strong majority of respondents (26 of 31) believed travel on Interstates and freeways (item 7, +1.7), and assigning that efficient carriers were also safe carriers. familiar routes to drivers (item 14, +1.6). Those rated overall as detrimental to safety included travel on low-speed road- Question 19 asked respondents to write in other comments ways (item 8, -1.6) and night driving (item 10, -0.7). Notice regarding carrier efficiencies or other practices that affect fleet

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41 TABLE 16 GENERAL RELATIONSHIP BETWEEN CARRIER EFFICIENCY AND SAFETY FOR OTHER EXPERTS (29) What is the relationship between carrier efficiency and safety? Circle the letter of the statement you most agree with. N (a) Highly efficient carriers tend also to be more safe than other carriers. 26 (b) Carrier efficiency and carrier safety are lar gely unrelated to each other. 2 (c) Highly efficient carriers tend to be less safe than other carriers. 0 (d) Don't know/no general opinion. 3 Total: 31 safety positively or negatively. It added, "For example, what To manage efficiency implies an organizational struc- carrier efficiencies affecting safety (positively or negatively) ture that can also manage risk. have we missed?" The following are selected responses: Management safety attitude; pressure by brokers; drivers Information About Respondents not being responsible on their time off and resting. Managers of well-managed operations pay attention to The years of motor carrier safety experience of the 32 other- all aspects of their operations. expert respondents, addressed by Question 21, ranged widely The biggest single determinant of overall safety is risk from 5 years to 40 years. The mean was 19.3 years. These exposure. Interstates, because they are divided traffic- respondents were also asked in Question 22 to indicate their ways with no at-grade intersections are 400% safer professional experience areas relating to motor carrier safety. than U.S. and state routes. More than 70% of fatal truck The breakdown is shown in Table 17. The percentages shown crashes occur on these latter roads, not Interstates where sum to well over 100%, because most respondents gave mul- all the enforcement attention and focus takes place. tiple responses. The results show that the experience base Carriers operating mostly on non-Interstate roads are of the other experts was both extensive and varied, with heavy much more at-risk than those that predominantly travel representation of individuals with backgrounds in govern- up and down Interstates. ment, industry trade associations, safety consulting, accident Driver monitoring with feedback on lane deviations and investigation and data analysis, and motor carrier safety hard-braking events. research. Intermixing passenger vehicles and heavy vehicles on two-lane freeways, especially with rolling terrain and TABLE 17 significant speed differentials. OTHER-EXPERT RESPONDENT EXPERIENCE AREAS Some efficiency measures in dispatch may result in non- Experience Area: No. rested drivers being given long runs that will result in (a) Government enforcement 7 fatigue. (b) Other government (e.g., rulemaking, policy) 15 Some standard practices with respect to vehicle type, operations, and schedules may promote efficiencies (c) Industry trade association 8 but not fit a driver's ergonomic needs, circadian rhythm, (d) Commercial driver 5 and temperament, which often leads to increased risk. (e) Carrier safety director/manager 3 Driver training programs. (f) Other carrier management position 3 Onboard monitoring of driving behavior so safety man- (g) Safety consultant or vendor to fleets 7 agers can provide feedback and incentives to increase (h) Accident investigation/data analysis 15 safety. Some survey questions are too simplistic in what is a (i) Motor carrier safety res earch 17 complex set of interdependencies. (j) Journalist 0 Need to adopt a systems-based approach, applying a (k) Driver trainer/training development 4 model or framework such as the Haddon Matrix. (l) Insurance for motor carriers 2 Using automated, tamper-resistant monitoring of HOS (m) Other 3 compliance would affect safety positively and also max- Average Number of Experience Areas/Respondent 2.8 imize efficiency.