Highway Safety Manual Training Materials (2012)

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7 The HSM overview training materials include presentation files, instructor and participant guides, sample problems, smart spreadsheets, and ancillary files to facilitate training activities. These training materials are based on the 12 modules depicted in Table 1. These 12 modules collectively introduce the audi- ence to the HSM basic content including methodology, pro- cesses, and recommended applications. Each module can be customized to accommodate individual presentation prefer- ences and styles. The presentation files also include embedded instructor notes to assist the presenter with intended content for the individual slides. Following several pilot training efforts, the NCHRP Proj- ect 17-38 team determined that the optimal instruction sequence may not always align with the order of the material as presented in the HSM. In some cases a module represents multiple chapters. The introduction of crash modification factors (CMFs), as an example, is presented in the HSM as part of the predictive models in Volume 2 and as a library in Volume 3. For the training, early instruction of CMFs is criti- cal to the analysis procedures and so this content was moved forward in the training sequence. The following summarizes the 12 modules and their HSM associated content. Module 1—Introduction to the Highway Safety Manual The intent of Module 1 is to introduce the participants to the workshop structure and purpose. To do this, the Module 1 presentation reviews the purpose and scope of the HSM and how the procedures contained in the manual apply to planning, design, operations, construction, and maintenance initiatives. The source information included in Module 1 originated from the HSM briefing presentation and material included in Chap- ter 1 (Introduction and Overview) of the HSM. At the conclusion of this module, participants will be able to • Define the purpose of the HSM; • Recognize the target audience: safety specialists, design and traffic engineers, and transportation planners; • Diagram the HSM structure and chapter content; • Relate the advantages of implementing the HSM for each target audience; • Describe the relevance of advanced road safety knowledge to HSM implementation; • Relate activities and projects relative to the HSM; and • Identify how to integrate the HSM into project development. Module 2—HSM Fundamentals and Terms The fundamentals presentation introduces workshop participants to essential safety information that is needed to establish a basic foundation of terminology and methods needed prior to a more detailed introduction of the vari- ous HSM safety procedures. Module 2 content is based on the HSM Chapter 3 (Fundamentals) and supplemented by example scenarios. In addition to the presentation, a sum- mary of HSM Workshop Acronyms is available in the front section of the participant guide (a similar list is included in the instructor guide). At the conclusion of this module, participants will have fundamental background that will enable them to • Recognize HSM safety measurement by crashes; • Describe data needs for the HSM; • Describe the evolution of crash estimation methods; • Recognize predictive methods in Volume 2, Part C of the HSM; and • Identify benefits and limitations in the evaluation of safety effectiveness. Module 3—Crash Modification Factors The use of CMFs (single values) or functions (equations) is the focus of Module 3. The HSM includes CMFs as part of self-contained safety predictive methods (in Volume 2) as well as a library of CMF types, base conditions, and applica- tions in the HSM Volume 3. Source material for this module, C h a p t e r 4 Description of the Course Materials

8• Define the predictive method, application, and limitations; • Compare the differences among predictive methods based on characteristics of roadway types; and • Demonstrate the predictive method. Module 5—Calibration and Predictive Method Specialized Procedures The HSM predictive procedures can be used for relative comparison purposes or they can be customized for local variations unique to a jurisdiction through the use of cali- bration. Example influences that can make local predictions different than the HSM values include differences in crash reporting thresholds or procedures, unique weather or ter- rain conditions, and high levels of animal-involved crashes. A jurisdiction may elect to develop regional safety performance functions in lieu of calibration. The appendix for Volume 2 of the HSM introduces the general procedure required to develop local calibration factors. The appendix also recom- mends that default crash distribution tables included in the HSM predictive chapters be customized for local crash dis- tributions. The values from these tables primarily affect the way CMFs are applied to specific crash types. The Volume 2 appendix also introduces the Empirical Bayes (EB) procedure that can be used to calculate expected crashes at a specific location using the predicted crashes (that represent an aver- age crash for a type of facility) in conjunction with historic (observed) crash information unique to the site of interest. A simplified example is also provided to demonstrate the cali- bration procedure (Sample Problem 5-1). At the conclusion of this module, participants will be able to • Describe how to calibrate predictive methods; • Describe the guidance of the HSM on the creation of jurisdiction-specific safety performance functions (SPFs); • Recognize how to replace default crash statistics with local values; and • Identify suitable EB Method applications. Module 6—Roadway Safety Management Process Overview The roadway safety management process is reviewed in Chapters 4 through 9 of the HSM. The associated modules can be taught collectively or an instructor may elect to teach only a portion of these modules. As a result, Module 6 pro- vides a very brief overview of the structure of the Volume 1 (Part B) content for the HSM. At the conclusion of this module, participants will be able to • Recognize the purpose of Volume 1 (Part B); • Describe the Volume 1 (Part B) structure; • Cite an overview of the six step Roadway Safety Manage- ment process; therefore, originated from Chapters 10, 11, and 12 (predic- tive methods) as well as Chapters 13, 14, 15, 16, and 17 of the HSM. In addition to the presentation, six sample problems (Sample Problems 3-1 through 3-6) are available so that par- ticipants can see sample calculations that incorporate the use of CMFs. At the conclusion of this module, participants will • Be familiar with crash modification factors and functions; and • Recognize Volume 3, Part D, as a resource for CMFs rela- tive to – Roadway segments; – Intersections; – Interchanges; and – Special facilities, geometric situation, and road networks. Module 4—Predictive Methods The HSM includes predictive methods for rural two-lane roads, rural multilane highways, and urban and suburban arterials. Module 4 introduces the common predictive meth- od analysis procedure required for applying the predictive methods. These methods are reliable and repeatable quanti- tative assessment procedures that are scientifically based and can help confirm that resources are distributed in a manner that effectively enhances safety. This Module 4 presentation introduces the predictive methods, provides an example application for rural two-lane roads, and introduces an exer- cise example for comparing two design options to existing conditions. A rural two-lane intersection in-class exercise and two additional sample problems (Sample Problems 4-1 and 4-2) are available for participants to begin applying the predictive methods to potential applications. The intent of the in-class exercise is for participants to manually work one simple application. The predictive methods combine safety performance functions, CMFs, and calibration factors to esti- mate the predicted number of crashes. Since this procedure can require multiple calculations, the training material also includes smart spreadsheets for the three road types. These spreadsheets are formatted to resemble the HSM worksheets included in Chapters 10, 11, and 12. The in-class exercise and the two sample problems are also provided as completed sample problem spreadsheets so users can see specific cal- culations. In many of the pilot training workshops, the par- ticipants requested that interactive computer lab exercises be included in Module 4. The worksheets and sample problems are constructed so that this expanded module content can be incorporated in more detailed training if the workshop participants’ expertise deems this appropriate. At the conclusion of this module, participants will be able to • Explain the predictive method and the analysis process; • Identify required data for basic and supplemental analysis;

9 Module 9—Diagnosis and Countermeasure Selection The presentation for Module 9 introduces methods for diagnosing problems and their potential contributing crash factors and then demonstrates how to select appropriate countermeasure or solutions. This module is based on HSM Chapter 5 (Diagnosis) and Chapter 6 (Select Countermea- sures). The case study previously introduced with Module 7 is extended into Case Study 9-1 to address a specific location (Intersection 2 from the previous case study). A companion spreadsheet for evaluations over a 30-year period is provided on the accompanying CD-ROM. At the conclusion of this module, participants will be able to • Describe the diagnosis process; • Recognize the importance of crash and supporting data; • Recognize how field conditions influence diagnosis; • Identify contributing factors; and • Select potential countermeasures. Module 10—Economic Appraisal and Prioritization Module 10 introduces a sample of the economic appraisal procedures introduced in the HSM Chapter 7 (Economic Appraisal) and then demonstrates how to prioritize safety enhancement projects using these procedures as introduced in Chapter 8 (Prioritize Projects). These ranked and prioritized outcomes can be used to select specific countermeasure treat- ments as well as prioritize various candidate improvement proj- ects. The safety management case study introduced in Module 7 is then applied to Case Study 10-1 where candidate counter- measures are assessed for three specific intersections including Intersection 2 from Module 9. Three companion spreadsheets (one for each of the three intersections) are provided on the accompanying CD-ROM and demonstrate how an economic appraisal and prioritization could be applied to each location. At the conclusion of the module, participants will be able to • Describe an overview of project benefits and costs; • Define economic evaluation methods for individual sites; • Recognize non-monetary considerations; • Identify three prioritization methods; and • Describe applications of economic appraisal and prioriti- zation methods. Module 11—Safety Effectiveness Evaluation The final step of the roadway safety management process is a safety effectiveness evaluation. This analysis procedure is included in Module 11 and represents HSM Chapter 9 (Safety • Describe how to use Volume 1 (Part B); and • State the benefits of using the Roadway Safety Manage- ment process. Module 7—Network Screening The Module 7 presentation introduces the concept of net- work screening. It provides an outline of the network screen- ing process and various reference populations, performance measures (strengths and limitations), and available screening methods. The HSM introduces a variety of analysis methods that can be used for this purpose. This module presents a list of the methods in a tabular format in the order of greater reliability. Module 7 introduces a case study that provides an application of the safety management process. This example is introduced with the Case Study 7-1 sample calculations. The details of this case study are continued and expanded in the subsequent modules. The source information for this module is HSM Chapter 4 (Network Screening). At the conclusion of this module, participants will be able to • Recognize the network screening process; • Establish reference populations; • Select performance measures; • Select appropriate screening methods; and • Screen and evaluate results. Module 8—Human Factors Network screening helps us understand where crashes occur or are likely to occur. Understanding human factors helps us identify why those crashes are occurring, that is, what human factors are contributing to the crashes. Chapter 2 of the HSM specifically introduces the role of human factors in road safety, discusses the driving task model, introduces driver characteristics and limitations, highlights the role of positive guidance, and reviews impacts of road design on the driver. Module 8 begins the process of diagnosis (e.g., identifying contributing crash factors) and focuses on human factors. Though human factors are not explicitly a part of the HSM roadway safety management process, the placement of this module immediately before diagnosis and counter measure selection is strategic to ensure that human factors issues are recognized during the diagnosis process. The presentation for human factors includes an awareness test video that can be used to introduce the concept of sustained inattentional blindness for dynamic events. At the conclusion of this module, participants will be able to • Describe human factors and their role in road safety; • Recognize the impact of road design on the driver; and • Describe how human factors are integrated within the HSM.

10 • Describe evaluation study designs; • Identify benefits and limitations of evaluation study designs; • Identify appropriate methods to use based on available data; and • Describe an example safety evaluation application. Module 12—HSM Summary and Review The concluding presentation is Module 12. The goal of this module is to end the workshop with an overview of what was covered and a review of the key learning outcomes presented in the workshop. Items such as how an agency can move for- ward and the appropriate next steps are topics for discussion included with this presentation. This module also reviews the project development process and how the HSM can and should be integrated at each phase of this process. Effectiveness Evaluation). This step in the process occurs after selected projects have been implemented. It is critical to verify that the projects have had the intended impact on safety so that decisions related to these safety expenditures can be refined for future analysis. The case study integrated through the previous roadway safety management modules (Modules 7, 9, and 10) concludes with Case Study 11-1 where historic (observed) crash data is used to supplement the pre- dictive procedure and assess the performance of a safety enhancement project. This sample problem is supplemented by a companion spreadsheet that shows the individual cal- culations for the case study. In addition to Case Study 11-1, the training material also includes a second EB example (see Sample Problem 11-2). At the conclusion of this module, participants will be able to • Describe evaluation methods; • Recognize the importance of safety evaluations;