April 18, 2002

Refer to: HOTO-1

U.S. Department
of Transportation

Federal Highway
Administration

Mr. Gary Thompson State Traffic Engineer Office of Traffic Engineering Mail Stop 725, 2nd Floor Minnesota Department of Transportation 395 John Ireland Blvd St. Paul, MN 55155-1899

Dear Mr. Thompson:

Thank you for your letter of December 10, 2001, requesting experimentation with an advance warning sign design for roundabouts. We apologize for the delay in responding to your request.

All first class mail sent through the U.S. Postal Service to Federal agencies in the District of Columbia must be processed in a special way to protect government employees from the possibility of handling anthrax-tainted mail. The irradiation process delays delivery by several weeks.

We have reviewed your request and offer the following comments:

1. Please find enclosed the requirements for a Request to Experiment from Section 1A.10 Interpretations, Experimentations, and Changes of the MUTCD. Please put the information in your request into the format detailed in the 3`d Guidance statement for items A through I.

2. The evaluation or research plan in item G should include quantitative data describing the performance of the experimental device.

3. Suggest a minor modification to add arrow heads to the each of the three "stems" in the symbol (i.e., to the right, the top and to the left) based upon feedback received by the MUTCD team regarding similar symbol designs in use for traffic circles.

Please revise the request to experiment to incorporate the comments noted above and you may submit the information by FAX (708-283-3501) to expedite the approval process. For future reference purposes, we have assigned the following official experimentation number and title to your request: 2-493(Ex) - "Advance Warning Sign for Roundabouts - MNDOT." Please refer to this number in future correspondence.

We look forward to receiving notifications of implementation dates and to your semiannual progress reports and final report. If we can be of further assistance, please contact Fred Ranck, Safety Engineer in the Midwestern Resource Center at (708) 366-0857.

Sincerely yours,
Shelley T. Rowe, P.E.
Director, Office of Transportation
Operations

Enclosure
FH WA:IiOTO-1:EHuckaby:adp:4/17/02:69064
cc: HOTO-1 HOST-1 HOTO-1(EHuckaby/Swainwright)
All Resource Center HDA-MI(2) Mr. Bob Garrett, NCUTCD
Mr. Roger Wentz, ATSSA Mr. Fred Ranck
Chron 3408 Reader 3408

DF(2-493(Ex))
M:\MUTCD\SIGNS\SYMBOLS\MNDOT round about symbol sign.doc