This searchable CD-ROM presents a synthesis of current information and operating practices related to roadside safety and is presented in both metric and U.S. Customary units. The roadside is defined as that area beyond the travelled way (driving lanes) and the shoulder (if any) of the roadway itself. The focus of this guide is on safety treatments that minimise the likelihood of serious injuries when a driver runs off the road. This guide replaces the 1996 AASHTO Roadside Design Guide. This 2002 Third Edition has been updated to include hardware that has met the evaluation criteria contained in NCHRP Report 350. Chapter 1 is an introduction. Chapter 2 discusses methods for selecting the appropriate alternative roadside safety enhancements. The discussion involves cost benefit analyses to determine a ranking of alternatives in the absence of better local information. Appendix A offers an example of one type of methodology for accomplishing a cost benefit analysis of various alternatives. Chapter 3 contains a discussion of the clear roadside concept. It also gives some relative clear zone values from which design guidance might be derived. Examples of the application of the clear zone values are also given. The chapter further includes a discussion of the treatment of roadside drainage features. Chapter 4 provides information on the use of sign and luminaire supports within the roadside environment. Both small and large signs are included, as well as breakaway and non-breakaway supports. The chapter concludes with discussions of miscellaneous roadside features such as mailbox supports, utility poles, and trees. Chapters 5, 6, 7, and 8 provide information concerning roadside barriers and crash cushions. Chapter 5 discusses roadside barriers. Appendix B gives selected details for these roadside barriers. Chapter 6 provides equivalent information for median barriers and Appendix C gives selected median barrier details. Chapter 7 includes information on appropriate bridge railings. Chapter 8 offers the latest state-of-the-practice information on barrier end treatments and crash cushions. Chapter 9 offers some discussion of the application of the roadside safety concept for the temporary conditions found in construction or maintenance work zones. For example, the chapter contains information on temporary barriers, truck-mounted attenuators, barricades, and other conditions commonly associated with work zones. Chapter 10 discusses the application of roadside safety in the urban environment. While much of the information presented in this publication applies to rural, high-speed conditions, this chapter offers information on urban roadside practices. Chapter 11 provides guidelines for erecting mailboxes on streets and highways. In addition, Appendices D and E provide a model regulation for erecting mailboxes and newspaper delivery boxes along public highways and an excerpt from the Postal Operations Manual that deals with delivery service policies and guidelines. A searchable CD-ROM of the text is included. (Author/publisher)
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