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7 CHAPTER TWO EVIDENCE AND PRODUCT REVIEW This chapter presents research findings and, where applica- equipment. This report addresses only their operational ble, product information relating to motor carrier risk avoid- use by carriers, not regulatory questions. ance strategies. Most of these are carrier efficiencies that also Project survey data are based on convenience samples have benefits, or at least potential benefits, for safety. The of responding safety managers and other experts. Survey chapter begins with a conceptual framework for Commercial data represent the opinions and practices of the respon- Vehicle Operations (CVO) risk avoidance strategies based dent samples, not of larger populations such as "all carrier on the Haddon Matrix (discussed here) and on subsequent safety managers." Safety-manager respondents generally considerations of how that concept could be better fitted to represented larger fleets with sufficient resources and motor carrier safety. The chapter then addresses the follow- safety interest to participate in national industry organi- ing carrier practices and issues: zations and meetings. Employing preventive maintenance; CONCEPTUAL FRAMEWORK FOR Reducing empty ("deadhead") trips; COMMERCIAL VEHICLE OPERATIONS Minimizing loading, unloading, and related delays; RISK AVOIDANCE STRATEGIES Optimizing routing and navigation Providing navigational and routing aids This section provides a conceptual framework for carrier oper- Assigning familiar routes to drivers; ational risk avoidance strategies based on past literature. The Selecting road type: divided versus undivided roads; Haddon Matrix (Haddon 1980) is a framework for under- Avoiding work zones; standing and designing crash reduction strategies. It provides Avoiding traffic; a conceptual structure for identifying factors that influence Emphasizing efficient scheduling: optimal times for safe crash occurrence by dividing the crash scenario in terms of travel; time frame (i.e., pre-crash, crash, and post-crash) and in terms Avoiding adverse weather; of the primary "actors" affecting the event (Howarth et al. Using higher-productivity vehicles; 2007). The "actors," or categories of factors affecting crashes, Using onboard computers and mobile communications; are the human (primarily driver), the vehicle, and the roadway Employing team driving; and environment. Thus, the conventional Haddon Matrix is Using EOBRs; a 33 matrix consisting of three rows (pre-crash, crash, and Optimizing fuel economy and safety post-crash) and three columns (human, vehicle, and roadway Speed limiters and environment). Table 1 presents the conventional Haddon Monitoring driver fuel economy; and Matrix with examples in each cell. Monitoring vehicle condition. The Haddon Matrix was a seminal, heuristic contribution The last four topics in this list were not among the topics origi- to motor vehicle safety and is a foundation for worldwide nally planned for the study, but were added based on survey programs to reduce crashes (Williams 1999; Runge 2003). responses and interview inputs. The chapter ends with a dis- However, Will Murray (Murray et al. 2003, 2009) and others cussion of whether there is a general relationship between effi- (e.g., Faulks and Irwin 2002) have pointed out that the ciency and safety, in industry and in CMV transport in particular. conventional Haddon Matrix is insufficiently detailed for conceptualizing the full array of interventions applicable to Three disclaimers are in order regarding the following CMV transport. Murray et al. (2003) added a column, "Man- discussion: agement Culture," and listed 33 carrier, industry, and gov- ernment practices that affect safety, with most in the pre-crash No product or service was formally evaluated for this time frame. Murray et al. (2009) reconceptualized and fur- report. Company and brand names provided are illustra- ther expanded the columns to include six factors: tive of available products and services. Neither TRB nor this report endorses any company, product, or service. Management culture; There are regulatory issues and activities under way Journey; regarding several of the earlier noted practices and Road and site environment;

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8 TABLE 1 CONVENTIONAL HADDON MATRIX A ctor "/Factor Human Roadway/ Time Frame (Driver) Vehicle Environment Pre-Crash Driver licensing Brake conditions Roadway markings Driver training, etc. Crash avoidance Divided highways technologies, etc. Curves, etc. Crash Restraint use Vehicle size Guard rails Bone density, etc. Crashworthiness, etc. Embankments, etc. Post-Crash Victim general health Gas tank integrity EMS availability Rehabilitation, etc. Automatic collision EMS response, etc. notification, etc. People; tions to prevent imminent crashes, such as forward collision Vehicle; and warnings and similar crash avoidance systems. In Table 2, Society or community. "pre-trip" and "pre-threat" are combined in one row because some practices fall across both categories. Table 2 further reconceptualizes the matrix in the context of factors examined in the current report. As noted in the Another Haddon Matrix expansion in Table 2 is the sepa- introduction to this report, "pre-crash" encompasses several ration of "post-crash" into "post-crash/response" and "post- qualitatively different time frames: pre-trip, pre-threat, and crash/remediation." Because most commercial drivers are pre-crash impact. The risk avoidance strategies addressed in company employees or representatives, the post-crash period this report are all either pre-trip or pre-threat, in that they are extends to longer-term follow-ups, such as driver discipline efficiencies and other practices that reduce the likelihood and retraining. of imminent crash threats. The term "exposure avoidance" is used by one large trucking company contacted to character- The current project surveys, interviews, and literature ize these strategies. This is in contrast to pre-crash interven- reviews make distinctions between crash risk factors that are TABLE 2 CVO SAFETY MATRIX WITH CLASSIFICATION OF OPERATIONAL EFFICIENCIES AFFECTING SAFETY "Actor"/Factor Vehicle Government/ Driver: Driver: Design Roadway Road/ Industry/ Motor Enduring Temporary and Vehicle Design/ Environment Time Frame Society Carrier Traits States Equipment Condition Traffic Condition Pre-Trip/ Loading Vehicle Preventive Deadheads Work Pre-Threat Delays Size Maintenance Optimize Zones Optimize Onboard Monitor Routing Exposure Times of Computers Vehicle Divided to Adverse Travel & Comms. Condition Roads Weather Team EOBRs Exposure Drivers to Traffic Speed Optimize Limiters Times of Monitor Travel Fuel Economy Pre-Crash Crash Post-Crash/ Response Post-Crash/ Remediation