June 18, 2000

 

 

 

Docket Clerk, U.S. DOT Dockets

Room PL-401

400 Seventh Street, SW

Washington, D.C. 20590-0001

Re: Comments on FHWA Docket No. FHWA-99-6575

Dear Sir/Madam:

As a professional involved with traffic signals, I am concerned about some of the proposed changes to the Manual on Uniform Traffic Control Devices (MUTCD). The following comments are in regards to these proposed changes:

  1.  
  2. The elimination of the red arrow indication is not a good idea. These devices have a long history of successful use and are a practical self-explanatory traffic control device. The red arrow serves to differentiate turning and through movement indications from each other. The confusion that some drivers experience would appear to be related far more to education and familiarity rather than a conceptual flaw or purely due to target value issues.
  • Furthermore, the proposed change to circular red indications is flawed as it causes additional problems. Two such major problems are the potential of confusion generated by the similarity of the proposed indication with through movement indications and the required LEFT TURN SIGNAL sign can be very difficult to read at night (especially for elderly drivers).

    Finally, consider that turning movements are generally made at lower speeds and motorists are typically decelerating upon entering a turn lane. Given these conditions, red arrows are appropriate, as they are easily visible and distinguishable at the required distances and speeds involved.

    2. The MUTCD should warn designers that right turn overlap arrows should not be displayed simultaneously with their parent left turn arrow unless U-turns are either prohibited or a sign is posted requiring the U-turns to yield.

    3. Unnecessarily long pedestrian times can have a very detrimental effect on coordinated signal operation. They can force the use of higher cycle lengths which may increase motorist delay throughout the system. With large crossing distances, we just can't afford to arbitrarily use longer WALK times or slower walking speeds in calculating pedestrian clearance times. Long pedestrian clearance times can lead to increasing motorist frustration and breeding of motorist disrespect for the signal system (e.g. motorists are forced to wait while the pedestrian clearance times-out even though the pedestrian is long gone). To design a system in this manner is to invite problems.

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    • Please feel free to contact me if you have any questions concerning these comments.

     

    Sincerely,