Recent Email

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Email

From: "Wainwright, Scott"
Date: 2005/03/17 Thu AM 10:30:13 EST
To: "Hedtke Institute"

Subject: RE: red light running or No standard yellow light time

Dear Mr. Hedtke:

Thank you for your message to Mr. Rudy Umbs of the Federal Highway
Administration's Office of Safety about standards for the duration of the
yellow change interval for traffic signals.

The national Manual on Uniform Traffic Control Devices (MUTCD) is issued by the
Federal Highway Administration (FHWA) as the national standard for all traffic
control devices in the U.S., including traffic signals. The MUTCD may be
viewed online at http://mutcd.fhwa.dot.gov and you will find specific standards,
guidance, and options regarding the duration of the yellow change
interval in Part 4, specifically Section 4D.10. The national MUTCD recommends that
the yellow change interval be in the range of 3 to 6 seconds, with the longer
durations reserved for higher speed roadways. Within the range of 3 to 6
seconds, the state, city, and county road authorities have the flexibility to
determine the actual settings of yellow change intervals at individual
intersections under their jurisdiction.

However, the Institute of Transportation Engineers (ITE, website www.ite.org)
publishes guidelines for calculating the duration of yellow change intervals,
taking into account factors such as approach speeds of vehicles, width of
intersection, upgrades or downgrades on the approaches, percentages of heavy
vehicles (trucks), etc. Many States and local governments use the ITE
guidelines, which were developed based on scientific safety research, as the
basis of their individual policies for yellow light timing.

Also, you may be interested to know that the FHWA has recently received a
recommendation from the National Committee on Uniform Traffic Control Devices
(NCUTCD) for a change in Section 4D.10 of the MUTCD. The NCUTCD is a volunteer
organization of over 200 experts in traffic control devices employed by State
and local governments, universities, engineering consultant firms, automobile
associations, industry, and other entities involved in traffic controls. The
NCUTCD has recommended that Section 4D.10 be amended to require that the
durations of the yellow change interval and red clearance interval be based on
accepted engineering practices and that specific reference be made to the ITE
guidelines. FHWA will consider amending Section 4D.10 as a part of the formal
Federal rulemaking process that will lead to the next edition of the MUTCD.
The rulemaking process is anticipated to start in 2007 and be completed in 2008
with the issuance of a 2008 edition of the MUTCD.

I hope this information is helpful to you. Please take a just a couple of
seconds to double click on the attached Customer Service Feedback icon, answer
the three questions and submit. Thanks.

W. Scott Wainwright, P.E., PTOE
Highway Engineer, MUTCD Team
Federal Highway Administration
Office of Transportation Operations, HOTO-1
400 Seventh Street, SW, Room 3408
Washington, DC 20590