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11-005316A Buley drn (Std. 111)

Ms. Gloria M. Buley


Woodstock Safety Mirror Co., Inc.

40 Industrial Drive

Saugerties, NY  12477     

Dear Ms. Buley:

This responds to your letter of August 8, 2011 to this office and subsequent telephone conversations of September 21 and 22, 2011 with my staff, concerning a stop arm/mirror unit you manufacture.  Your letter and telephone conversations follow up on your previous correspondence in 2006 and 2007 to the National Highway Traffic Safety Administration (NHTSA), and also follows on an inquiry we received earlier this year from Congressman Maurice Hinchey on your behalf. 


The previous correspondence with NHTSA concerned a stop arm/mirror unit you designed to mount on the right side of a school bus.  In our interpretation letters of July 10, 2006 and March 26, 2007 from this office, we explained that your device would be considered a stop arm and mirror system subject to both Federal Motor Vehicle Safety Standard (FMVSS)

No. 131, School bus pedestrian safety devices, and FMVSS No. 111, Rearview mirrors.  Our previous correspondence with you focused on whether your stop arm/mirror unit could be installed on new school buses with only one stop arm on the left side. 

We explained in the 2007 letter that new school buses equipped with your product must be certified as meeting all applicable FMVSSs, including FMVSS No. 131.  Your product would be considered a supplemental school bus stop arm.  Under FMVSS No. 131, a supplemental stop signal arm on the right side of a school bus is permissible under Federal law provided:  (1) two compliant stop signal arms are already present on the left side of the bus; and (2) the additional, supplemental stop signal arm does not take the vehicle out of compliance with any applicable safety standards (with FMVSS No. 111 being the most relevant).

Regarding compliance of your product with FMVSS No. 111, we explained in the 2006 letter that:

Based on our analysis of the materials you submitted, we believe that your system would provide supplemental mirrors.  Supplemental mirrors are permissible, provided that they do not interfere with the performance of the mirrors required under FMVSS No. 111.  Your letter states that your companys mirror system would neither make inoperative nor diminish the performance of any other mirrors or safety devices currently required on school buses.  [A]ssuming that the statement is correct, your supplemental mirror would not be prohibited by Standard No. 111.



            In your telephone call, you asked about the possibility of your device not having features of a stop arm, i.e., you would reconfigure the device to be only a supplemental mirror system, meeting FMVSS No. 111, and not as a stop arm.  You are interested in this modification because you believe some States may be unwilling to specify a second stop arm on the left side of the school bus, which they would have to do before they could specify a stop arm on the right side.  You ask:  if your device were a supplemental mirror system and not a stop arm, could your device be installed on the right side of school buses that had only one stop arm on the left side.


            Based on our understanding of the information you provided, our answer is yes.  If your device were not a stop arm, it could be installed on the right side of the bus as a supplemental mirror system.  This assumes that the device met FMVSS No. 111 and did not make inoperative or diminish the performance of any other mirrors or safety devices currently required on school buses.  Requirements for your product as only a supplemental mirror system were discussed in the July 10, 2006 letter, see in particular in the quotation provided above applicable to supplemental mirrors.

            You asked whether the back of the mirror system may be hexagonal[1] and painted red.  The answer is yes.  Nothing in FMVSS No. 111 specifies color requirements or shapes for the backs of school bus mirror systems.  Therefore, FMVSS No. 111 does not prohibit the back of the mirror on your supplemental mirror system from being hexagonal or painted red.

            I hope this information is helpful.  If you have any further questions, please contact

Ms. Deirdre Fujita of my staff at (202) 366-2992.                 

                                                                                    Sincerely yours,


                                                                                    O. Kevin Vincent

                                                                                    Chief Counsel


Std. 111

[1] You state that the hexagonal shape is needed because it serves as the backing for the mirror system.  You advised my staff that cutting off the corners of the backing for a more rounded look could result in as much as $250,000 in machining costs to your small business.