U.S. Department of Transportation
Federal Highway Administration
400 Seventh St., S.W.
Washington, D.C. 20590

Refer to: HOTO-1

Mr. James H. Bloodgood
Traffic Operations Manager
Snohomish County Public Works
2930 Wetmore Avenue
Everett, WA 98201

November 4, 1999

Dear Mr. Bloodgood:

We have reviewed your October 7 letter regarding your request for approval to experiment with in-roadway flashing warning lights and offer the following comments. As stated in Section 1A-6 of the Manual on Uniform Traffic Control Devices (MUTCD), please address the following in the evaluation plan:

The experimentation plan should be expanded to include the following:

• How the field observation data will be collected, e.g., by observers, using video, etc.?
• When the field data will be collected, e.g., day, night, peak, off-peak, week, weekend, etc.
• What subjective data will be collected, who and how many subjects, and how these data will be collected, e.g., by interview, questionnaire, etc.
• The amount of field and subjective data that will be collected.
• The statistical tests that will be used to evaluate the data.
• A statement describing how closely the experiment will be monitored, especially in the early stages of implementation.
• We also request that you include some safety assessment such as near misses, traffic conflicts, accidents, etc. Please specify.

In addition to the requirements found in Section1A.6 of the MUTCD, we offer the following comments:

• The sign you propose to use at the crosswalk with flashing amber LED lights is not in compliance with the MUTCD. This sign should not be used in this experimentation. A separate experimentation request would need to be approved before this sign could be used in this experimentation.
• Your experimentation with in-roadway flashing warning lights should include the installation of amber raised pavement markers at a separate crossing for comparison purposes.

Your request to experiment with the in-roadway flashing warning lights for crosswalks will be approved, contingent on receipt and review of a more detailed evaluation plan including the items requested above.

For future reference purposes, we have assigned the following official experimentation number and title to your request: IV-166(Ex) -"In-Roadway Flashing Warning Lights." Please refer to this number in future correspondence.

If we can be of further assistance, please contact Ms. Louisa M. Ward on 202-366-4372.

Sincerely yours,

Donald P. Steinke
Director, Office of Transportation Operations