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4 Guidelines for Selection of Speed Reduction Treatments at High-Speed Intersections apply to suburban and rural roadways. Speeds on roadway segments outside the influence area of an intersection are not addressed; however, the relationship between segment speed and speed within the intersection influence area is addressed. Although this document focuses on public roadway intersections, many principles also apply to private driveways that include public road- way-like features. Intersections are discrete features of roadway or corridor segments. They frequently occur in urban conditions, but are found more sporadically in rural and suburban areas. Some of the visual cues, physical features, and perceptible qualities that influence operating speeds on road- way segments are different from those that influence operating speed at intersections. The Guidelines focus on speed reduction treatments within an intersection's geometric and operational influence areas and do not specifically address speed reduction in roadway segments. It is necessary to define the influence area of an intersection to differentiate between reducing speeds on the segment rather than the intersection. The influence area of an intersection includes the area within which the typical section of the roadway segment is modified and that is influ- enced by traffic operations (i.e., queuing and deceleration) related to the intersection. This is shown schematically in Exhibit 1-1. 1.4 Report Organization Section 1 introduces the Guidelines and presents their purpose, scope, and applicability. Section 2 discusses the fundamentals of speed. Section 3 leads users through the process of con- sidering and implementing speed reduction treatments on intersection approaches. Section 4 describes speed reduction treatments in detail. Appendices A through D provide a treatment implementation process framework, scenario-based case studies, testing data and results from the testing plan, and references to other relevant studies, respectively. Exhibit 1-1. Roadway segment and intersection area.