Interim Approval for Optional Use of an Alternative Signal Warrant 7 – Crash Experience (IA-19)

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U.S. Department of Transportation Federal Highway Administration

Memorandum

Subject:	INFORMATION: MUTCD – Interim Approval for Optional Use of an Alternative Signal Warrant 7 – Crash Experience (IA-19)	Date: February 24, 2017
From:	Martin C. Knopp Associate Administrator for Operations	In Reply Refer To: HOTO-1
To:	Federal Lands Highway Division Engineers Division Administrators

Purpose: The purpose of this memorandum is to issue an Interim Approval for the optional use of an alternative Warrant 7, Crash Experience, when performing a traffic control signal needs study. Interim Approval allows interim use, pending official rulemaking, of a new traffic control device, a revision to the application or manner of use of an existing traffic control device, or a provision not specifically described in the Manual on Uniform Traffic Control Devices for Streets and Highways (MUTCD).

Background: Section 4C.08 of the 2009 edition of the MUTCD contains the provisions for a traffic control signal Warrant 7 based on past crash experience at the location being studied. At the current time in order to satisfy the criteria for Warrant 7, Item B of Paragraph 2 in Section 4C.08 requires the engineer performing the traffic control signal needs study to document that "five or more reported crashes, of types susceptible to correction by a traffic control signal, have occurred within a 12-month period, each crash involving personal injury or property damage apparently exceeding the applicable requirements for a reportable crash."

This threshold of five or more crashes has been in use for a long time. It can be found in Section 307 of the earliest (1935) edition of the MUTCD. Because the basis of this threshold of five or more crashes is not known¹, a National Cooperative Highway Research Program (NCHRP) research project, which is described in the next section of this memorandum, was developed and performed with its purpose being either to validate the accuracy and relevance of the "five or more crashes" threshold or to recommend an improved crash experience traffic signal warrant.

Research on Warrant 7: A research project was performed under NCHRP Project 07-18, "Crash Experience Warrant for Traffic Signals". The research resulted in updated criteria, which is based on either one year or three years of recent crash experience, for the number of crashes portion of Warrant 7.

The National Committee on Uniform Traffic Control Devices (NCUTCD) has requested that the FHWA revise the crash warrant in the next edition of the MUTCD based on research documented in the Final Report² for NCHRP Project No. 07-18. This change request has been designated by the FHWA as Official Ruling 4(09)-42 (C).

FHWA Evaluation of Results: The Office of Transportation Operations has reviewed the research findings and the NCUTCD's change request and concurs with the conclusions of the research and the request from the NCUTCD.

The primary advantage of allowing the optional use of an alternative Item B in Paragraph 2 of Section 4C.08 of the 2009 edition of the MUTCD is that practitioners will be able to use a research-based method of analyzing reported crashes that takes into consideration (1) the number of crashes occurring over a three-year period in addition to a one-year period and (2) the number of legs at the location.

Conditions of Interim Approval: This Interim Approval does not create a new mandate compelling the alternative Item B in Paragraph 2 of Section 4C.08, but will allow agencies to use the alternative Item B, pending official MUTCD rulemaking, when performing a traffic control signal needs study.

The FHWA will grant permission for the optional use of an alternative Item B in Paragraph 2 of Section 4C.08 of the 2009 edition of the MUTCD under this Interim Approval to any jurisdiction that submits a written request to the Office of Transportation Operations. A State may request Interim Approval for all jurisdictions in that State. Jurisdictions seeking permission to use an alternative Item B in Paragraph 2 of Section 4C.08 under this Interim Approval must agree to:

Comply with the technical conditions detailed below, and
Maintain an inventory list of all locations where the alternative Item B in Paragraph 2 of Section 4C.08 was used to justify the installation of a traffic control signal, and
Comply with Item D in Paragraph 18 of Section 1A.10.

Technical Conditions:

The use of an alternative Item B in Paragraph 2 of Section 4C.08 is optional. However, if an agency opts to use the alternative Item B, such use shall be in accordance with the same provisions that currently exist in the 2009 edition of the MUTCD for Warrant 7, Crash Experience, except that the existing Item B in Paragraph 2 may be replaced by the following provisions:

At least one of the following conditions applies to the reported crash history (where each reported crash considered is related to the intersection and apparently exceeds the applicable requirements for a reportable crash):
1. The number of reported angle crashes and pedestrian crashes within a one-year period equals or exceeds the threshold number in Table IA-19-1 for total angle crashes and pedestrian crashes (all severities); or
2. The number of reported fatal-and-injury angle crashes and pedestrian crashes within a one-year period equals or exceeds the threshold number in Table IA-19-1 for total fatal-and-injury angle crashes and pedestrian crashes ; or
3. The number of reported angle crashes and pedestrian crashes within a three-year period equals or exceeds the threshold number in Table IA-19-2 for total angle crashes and pedestrian crashes (all severities); or
4. The number of reported fatal-and-injury angle crashes and pedestrian crashes within a three-year period equals or exceeds the threshold number in Table IA-19-2 for total fatal-and-injury angle crashes and pedestrian crashes; and

Table IA-19-1. Minimum Number of Reported Crashes in a One-Year Period

**Urban Area**
Number of through lanes on each approach		Total of Angle and Pedestrian Crashes (all severities)^a		Total of Fatal-and-Injury Angle and Pedestrian Crashes^a
Major Street	Minor Street	Four Legs	Three Legs	Four Legs	Three Legs
1	1	5	4	3	3
2 or more	1	5	4	3	3
2 or more	2 or more	5	4	3	3
1	2 or more	5	4	3	3

**Rural Area ^b**
Number of through lanes on each approach		Total of Angle and Pedestrian Crashes (all severities)^a		Total of Fatal-and-Injury Angle and Pedestrian Crashes^a
Major Street	Minor Street	Four Legs	Three Legs	Four Legs	Three Legs
1	1	4	3	3	3
2 or more	1	10	9	6	6
2 or more	2 or more	10	9	6	6
1	2 or more	4	3	3	3

^a Anglecrashes include all crashes that occur at an angle and involve one or more vehicles on the major street and one or more vehicles on the minor street
^b "Rural Area" values apply to intersections where the major-street speed exceeds 40 mph or intersections located in an isolated community with a population of less than 10,000

Table IA-19-2. Minimum Number of Reported Crashes in a Three-Year Period

**Urban Area**
Number of through lanes on each approach		Total of Angle and Pedestrian Crashes (all severities)^a		Total of Fatal-and-Injury Angle and Pedestrian Crashes^a
Major Street	Minor Street	Four Legs	Three Legs	Four Legs	Three Legs
1	1	6	5	4	4
2 or more	1	6	5	4	4
2 or more	2 or more	6	5	4	4
1	2 or more	6	5	4	4

**Rural Area**
Number of through lanes on each approach		Total of Angle and Pedestrian Crashes (all severities)^a		Total of Fatal-and-Injury Angle and Pedestrian Crashes^a
Major Street	Minor Street	Four Legs	Three Legs	Four Legs	Three Legs
1	1	6	5	4	4
2 or more	1	16	13	9	9
2 or more	2 or more	16	13	9	9
1	2 or more	6	5	4	4

^a Angle crashes include all crashes that occur at an angle and involve one or more vehicles on the major street and one or more vehicles on the minor street
^b "Rural Area" values apply to intersections where the major-street speed exceeds 40 mph or intersections located in an isolated community with a population of less than 10,000

Any questions concerning this Interim Approval should be directed to Mr. Bruce Friedman at bruce.friedman@dot.gov.

cc:
Associate Administrators
Acting Chief Counsel
Chief Financial Officer
Directors of Field Services
Director of Technical Services

¹ Crash Experience Warrant for Traffic Signals; NCHRP Web-Only Document 204; Page 1; July 5, 2014; which can be accessed at http://www.trb.org/Main/Blurbs/171359.aspx.

² Crash Experience Warrant for Traffic Signals; NCHRP Web-Only Document 204; July 5, 2014; which can be accessed at http://www.trb.org/Main/Blurbs/171359.aspx.


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