Changes and experimentations for the Manual on Uniform Traffic Control Devices

Information on Interpretations, Experimentations, and Interim Approvals

The standard for traffic control devices in Washington state is the 11^th Edition of the Manual on Uniform Traffic Control Devices (MUTCD) with Washington State specific modifications (WAC 468-95).

See the Federal Highway Administration's (FHWA) Official Rulings database for interpretations and approved changes to the MUTCD, and approved experimentations of traffic control devices in Washington and other states.

Requesting an experimentation for a traffic control device that has not been tested:

Local and state agencies can request an experimentation from FHWA to test a new traffic control device that is either:

• Not in the 11^th Edition of the MUTCD and has not been tested.
• In the 11^th Edition of the MUTCD, but the device would be used in a new way (different size, type, or location) that has not been tested.

Request to be included in WSDOT's statewide interim approval to use a traffic control device that has been tested but is not in the MUTCD:

Local and state jurisdictions that want to use a traffic control device that has been tested or is in the process of being tested and is being considered for addition to the next edition of the MUTCD can request an interim approval from FHWA. Agencies can request site specific approval or jurisdiction-wide approval.

A local jurisdiction that wants to use WSDOT's statewide approval may do so. The agency must first contact WSDOT by email to notify us that it will use the device under the statewide approval. As a condition of statewide approval from FHWA, the agency must either 1) provide WSDOT a list of all locations where the traffic control device will be installed and must provide an updated list when locations are added or removed or 2) keep a list of all locations where the traffic control device is installed. This works like a recall. If FHWA should find the device to not be effective, FHWA will ask WSDOT to notify all the agencies using the device to remove them.

WSDOT statewide interim approvals for use on local jurisdiction-owned roadways and state highways:

Get definitions and specific requirements 

• IA-23.12 — Residential Driveway Temporary Signal

Interim Approvals issued under the 2009 MUTCD for devices that have been incorporated into the 11th Edition of the MUTCD, either in whole or in part, have been terminated by FHWA and are no longer in effect.