Technical Resources

Traffic Engineering Resources

The following is a listing of the most recent publications for this topic.

PUBLICATION TITLE
ITE Virtual Drop-In Session: Correlating Crashes with Conflicts using Video Based Road Safety Analytics
Convener: Paul St.-Aubin, Transoft Solutions
Sep 29, 2020
ITE Virtual Drop-In Session: Cybersecurity and Traffic Signals
Conveners: Joseph Gregory, FHWA and Ed Fok, FHWA
Jul 2, 2020
ITE Virtual Drop-In Session: What is the Effect of the Coronavirus on Traffic Crashes? Now and in the Future
Convener: Rudy Umbs, P.E., RSP2I, Tindale Oliver
Apr 28, 2020
ITE Virtual Drop-In Session: Transportation Funding and Traffic Signals
FHWA's Eddie Curtis answers the question: I am a Traffic Engineer with an Agency with 20 (or Fewer) Signals and We Have Funding to Upgrade Them. Where Do I Start?
Apr 6, 2020
Guidelines for Determining Traffic Signal Change and Clearance Intervals
ITE has published guidance on yellow change and red clearance intervals for signalized intersections. The goal of this guidance is to create a consensus methodology for calculating and evaluating traffic signal change intervals that can be consistently implemented by transportation agencies. The recommendations presented should yield reasonable times for the yellow change and red clearance intervals for traffic signals, assisting transportation professionals in enhancing intersection safety, maintaining reasonable traffic flow, and providing for movement of vehicles, bicycles, and pedestrians.
Mar 2, 2020
An Explanation of Mats Järlström's Extended Kinematic Equation
Since the yellow indication was first added to traffic signals in 1920, the proper interval duration has been robustly debated.1 Seemingly, the timing of the yellow indication appears straightforward. However, determining the illumination interval is quite intricate since it is part of a complex system of physical and human-made laws, technology, and human behavior that all must operate compatibly.
Feb 26, 2020
An Extended Yellow Change Interval Solution Derived from GHM's Critical Distance
The critical distance is the foundation to Gazis, Herman and Maradudin's (GHM) universally adopted minimum yellow traffic signal timing solution presented in their 1960 paper, "The Problem of the Amber Signal Light in Traffic Flow" [1]. However, GHM's (permissive [2]) minimum yellow signal duration is limited in its application since they only accounted for vehicles moving at constant velocity traversing a minimum safe and comfortable stopping distance referenced a level intersection's stopping line, aka GHM's critical distance.
Feb 26, 2020
Guidelines for Determining Traffic Signal Change and Clearance Intervals
ITE has concluded a years-long effort to issue guidance on yellow change and red clearance intervals for signalized intersections. The final version of the Recommended Practice Guidelines for Determining Traffic Signal Change and Clearance Intervals (RP-040B) has been adopted by the ITE International Board of Direction and is now available.1
Feb 26, 2020
Press Release: ITE Releases Recommended Practice for Traffic Signal Change and Clearance Intervals
The Institute of Transportation Engineers (ITE) has issued guidance on yellow change and red clearance intervals for signalized intersections. The recommended practice -- Guidelines for Determining Traffic Signal Change and Clearance Intervals -- has been adopted by the ITE International Board of Direction and is now available for purchase.
Feb 26, 2020
Traffic Signal Change and Clearance Intervals: Research Still Needed!
Yellow change and red clearance intervals have been a topic of research for at least the last 60 years. It would be easy to assume that we now know all we need to know about the subject and that the remaining challenge is merely to put what we know into practice. But there is still much about driver behavior at intersections during traffic signal changes that we don't know with certainty or completely understand. During the development of the ITE Guidelines for Determining Traffic Signal Change and Clearance Intervals Recommended Practice, current knowledge, research, and practice in this area was documented, but the following 11 areas of interest were identified where additional study or new research is needed to expand the body of knowledge. Research in these areas would be useful in further refining the concepts and procedures in the ITE Recommended Practice.
Feb 26, 2020
Yellow Change Intervals for Turning Movements Using Basic Kinematic Principles
This discussion will review various models of drivers approaching an intersection in both through and turning lanes and what yellow change interval may be necessary in those situations. It is an extension of the work of Gazis, Herman, and Maradudin's (GHM) in their seminal 1960 paper, "The Problem of the Amber Signal Light in Traffic Flow". GHM proposed the basic protocol used today for setting a minimum yellow change interval for through movements that would provide a motorist with a solvable solution to the stop or go problem encountered when the yellow signal is illuminated.
Feb 26, 2020
The Push and Pull of Engineering
As engineers, we are highly trained to identify a need or problem, solve it, and then iteratively improve it into a better "product" (e.g., solution, device, process). Typically, the product is then sold to customers. We can refer to this as the "push" of the solution, when we develop a product and push it into the market and onto society. Engineers practicing street design "push" their designs onto society, which is rooted in the practices and values from the 1950s and 1960s. What if we instead followed a "pull" methodology, where a street is designed to meet the desires and preferences of a wide range of customers or user groups? This would be analogous to the process that evolved in the automotive industry.
Nov 1, 2019
Drafting, Designing, and Deploying Wrong-Way Driving Countermeasures - A Florida DOT Initiative
This White Paper first discusses the efforts of the pioneering states in mitigating WWD incidents; the paper then documents the efforts FDOT has undertaken to tackle the WWD problem in Florida. The FDOT's strategy pertaining to the statewide policy, several WWD-related research projects, and pilot WWD countermeasure implementation projects, etc., are discussed in detail. This document also provides a brief overview of the ongoing and recently completed research efforts. This White Paper will assist other agencies in the U.S. and around the world to strategically address the WWD issue.
Sep 4, 2019
Application of Unmanned Aerial Vehicles to Inspect and Inventory Interchange Assets to Mitigate Wrong-Way Entries
Interchanges are critical elements of freeway and highway systems that provide access to nearby urban, suburban, and rural areas. Since the development of the interstate highway system in the 1950s, crashes associated with driving in the wrong direction on freeways have created a critical issue for transportation agencies. Wrong-way driving (WWD) occurs when a driver, either inadvertently or deliberately, drives in the opposing direction of traffic along a high-speed, physically divided highway or its access ramp. Reasons a driver may go in the wrong direction include but are not limited to, driving under the influence of substances such as alcohol or drugs, fatigue, and a confusing geometric roadway design. WWD crashes are known for their tendency of being more severe than other types of freeway crashes, which result in more fatalities due to them being mostly head-on or opposite-direction sideswipe collisions. According to the National Highway Traffic Safety Administration (NHTSA) Fatality Analysis Reporting System (FARS) database, during 2004 to 2011, an average annual total of 359 people perished in 269 fatal WWD crashes. This means that the average number of fatalities per WWD fatal crash was 1.33, as compared to the 1.09 death rate for all other fatal motor vehicle crashes, thus necessitating further evaluation and action.
Jul 1, 2019
Big Results with a Mini Roundabout - Webinar Question Log
Big Results with a Mini Roundabout - Webinar Question Log
May 10, 2019
Preemption of Traffic Signals Near Railroad Crossings
The Institute of Transportation Engineers (ITE) is preparing this report to reflect the current state-of-the-practice and to provide the user with a broad overview of key considerations for the preemption of traffic signals near railroad grade crossings. Where a signalized intersection exists in close proximity to a railroad crossing and either queues from the intersection impact the crossing or queues from the crossing impact the intersection, the railroad signal control equipment and the highway traffic signal control equipment should be interconnected. The normal operation of the traffic signals controlling the intersection should be preempted to operate in a special control mode when trains are approaching.
Apr 30, 2019
ITE GRADE CROSSING STANDING COMMITTEE 102-02 Draft Meeting Minutes August 21, 2018
ITE GRADE CROSSING STANDING COMMITTEE 102-02 Draft Meeting Minutes August 21, 2018
Jan 15, 2019
High-Speed Rail: What Does America's Largest Public Works Project Mean for Transportation Planners and Engineers?
High-Speed Rail: What Does America's Largest Public Works Project Mean for Transportation Planners and Engineers?
Sep 1, 2018
Designing New Features to Control Right-Turn on Red
Designing New Features to Control Right-Turn on Red
Aug 29, 2018
METRO Green Line: Washington Ave Pedestrian Mall
METRO Green Line: Washington Ave Pedestrian Mall
Aug 29, 2018