In this online engineering PDH course, estimates are discussed of the crash reduction expected if various countermeasures are implemented with respect to intersection crashes. The estimates are presented as Crash Reduction Factors (CRFs). Traffic engineers and other transportation professionals can use the information contained in this course when asking the following types of question: Which countermeasures might be considered at the signalized intersection of Maple and Elm streets, an intersection experiencing a high number of total crashes and left-turn crashes? What change in the number of total crashes and left-turn crashes can be expected with the implementation of the various countermeasures? To answer questions like these, in this course CRFs are presented in separate tables for signalization, geometric, and signs/markings/operational countermeasures.

In this online engineering PDH course, estimates are discussed of the crash reduction expected if various countermeasures are implemented with respect to intersection crashes. The estimates are presented as Crash Reduction Factors (CRFs). Traffic engineers and other transportation professionals can use the information contained in this course when asking the following types of question: Which countermeasures might be considered at the signalized intersection of Maple and Elm streets, an intersection experiencing a high number of total crashes and left-turn crashes? What change in the number of total crashes and left-turn crashes can be expected with the implementation of the various countermeasures? To answer questions like these, in this course CRFs are presented in separate tables for signalization, geometric, and signs/markings/operational countermeasures.

This course is based on the document, Toolbox of Countermeasures and Their Potential Effectiveness for Intersection Crashes, FHWA-SA-10-005 – November 2009, which can be accessed at https://safety.fhwa.dot.gov/intersection/other_topics/fhwasa10005/docs/brief_8.pdf.

Learning Objectives

• Define “crash reduction factors”;
• Identify CRFs for signalization, geometric, and signs/markings/operational countermeasures;
• Explain how crash severity is taken into account in choosing an appropriate countermeasure; and
• Explain how existing control information, such as no signal, signal, stop, or stop/yield is taken into account in choosing an appropriate countermeasure.