"This synthesis will be of interest to traffic engineers in federal, state, provincial, and local transportation agencies who are responsible for the design and operation of safe and efficiency highway systems. It will also be useful to consulting traffic engineers, sign manufacturers, and vendors in the private sector who assist governmental clients in the application of changeable message sign (CMS) and other intelligent transportation systems (ITS) technology. It is an update of NCHRP Synthesis no. 61 (1979)."--Avant-propos.

This document presents a synthesis of current information and operating practices related to roadside safety and is developed in metric units. The roadside is defined as that area beyond the traveled way (driving lanes) and the shoulder (if any) of the roadway itself. The focus of this guide is on safety treatments that minimize the likelihood of serious injuries when a driver runs off the road. This guide replaces the 1989 AASHTO "Roadside Design Guide."

The objective of this study was to develop and test word and symbol traffic control and hazard messages for portable changeable message signs (PCMSs). The messages were designed for the standard PCMS with three lines of eight characters. First, a comprehensive listing of candidate PCMS messages was developed. This was done by interviewing State highway engineers, surveying PCMS manufacturers and questioning motorists. In those situations where subjects did not express an overwhelming sign preference additional field testing was done. The detection distances of the candidate messages were determined using a PCMS under both day and night conditions.

"The 2009 AASHTO Transportation Glossary is an update and revision of the 1983 Transportation Glossary and the 1998 Transportation Glossary, which was unpublished. The largest additions in terminology were in bridge and drainage subjects. The new Glossary also includes lists of organizational acronyms, abbreviations, and other glossary references. Terms and definitions in this glossary were taken from an unpublished 1998 AASHTO Glossary and supplemented with definitions listed in AASHTO publications issued after 1998. Several additional sources were also referenced, including the Highway Capacity Manual, Manual on Uniform Traffic Control Devices, Code of Federal Regulations-Title 23, an FHWA list of roundabout terminology, and the Transportation Research Thesaurus. Glossary terms are listed in alphabetical order regardless of transportation mode. However, the glossary also includes two indexes-subject area and keyword-which provide cross references for the user."--AASHTO Bookstore website (viewed June 24, 2.