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Interpretation ID: 2513y

Mr. J. A. Schurger
Vehicle Improvement Products, Inc.
l5l S. Ram Road
Antioch, IL 60002-l937

Dear Mr. Schurger:

This responds to your request for an interpretation of Standard No. l0l, Controls and Displays. We apologize for the delay in responding to your letter. You described a proposed design for heavy trucks in which a "switch package" would be located in the center of the steering wheel, along the center spokes. The switch package would include controls for the horn, turn signals, cruise control, headlights (master lighting switch), marker lamps, hazard warning signal and high beam. You noted that Standard No. l0l requires the identification of certain controls to be "perceptually upright," and asked whether identifying symbols which rotate along with the steering wheel would be considered to meet this requirement. As discussed below, it is our opinion that such identification would not be considered to be perceptually upright to the driver.

By way of background information, the National Highway Traffic Safety Administration (NHTSA) does not provide approvals of motor vehicles or motor vehicle equipment. Under the National Traffic and Motor Vehicle Safety Act, it is the responsibility of the manufacturer to ensure that its motor vehicles or equipment comply with applicable safety standards. The following represents our opinion based on the facts provided in your letter.

Section S5.2.l of Standard No. l0l requires certain vehicle controls to be identified by specified symbols or words and for the identification to be placed on or adjacent to the control. That section also requires that "(t)he identification shall, under the conditions of S6, be visible to the driver and, except as provided in S5.2.l.l and S5.2.l.2, appear to the driver perceptually upright." The identification of several of the controls that you propose to locate on the steering would be subject to the "perceptually upright" requirement.

Under your proposed design, the identification of controls would rotate along with the steering wheel. The identification would not be perceptually upright to the driver except when the steering wheel is in a centered position. Since rotation of the steering wheel is a necessary and routine part of driving, the identification would often not be perceptually upright to the driver. It is therefore our opinion that identification of controls that rotate with the steering wheel would not be considered perceptually upright to the driver. We note that there is no provision in Standard No. l0l that limits the "perceptually upright" requirement to conditions where the steering wheel is centered.

This interpretation is consistent with past agency practice. In a July l984 notice establishing a requirement to identify the horn control with a specified symbol, NHTSA addressed commenter concerns about how Standard No. l0l's requirement that identification be perceptually upright might apply to horn controls located on the steering wheel. 49 FR 30l9l, 30l94; July 27, l984. The commenters noted that it is impossible for such horn symbols to be perceptually upright at all times. In response to the comments, the agency included a provision that the horn symbol need be perceptually upright only when the vehicle, aligned to the manufacturer's specification, has its wheels positioned for the vehicle to travel straight forward, i.e., when the steering wheel is centered. It would not have been necessary for the agency to establish this special provision for horn symbols if identification of controls located on the steering wheel was considered to be perceptually upright in the absence of such provision. (We note that NHTSA later decided to drop the perceptually upright requirement for the horn symbol. However, that decision does not affect the above analysis.)


Stephen P. Wood Acting Chief Counsel ref:l0l d:6/6/90