Interpretation ID: aiam4211
Vice-President
Spartan Transit Supply Corp.
325 Fairlane Drive
Spartanburg
SC 29302;
Dear Mr. Huentemann: This responds to your letter dated June 17, 1986, asking how ou regulations affect a convex outside mirror manufactured by your company. In your letter, you state that this convex mirror has a reflective surface of 92.5 square inches, and would be used on the curb side of a transit bus. You also state that this convex mirror has a radius of curvature of 94.5 inches. You specifically asked whether this mirror can be used on the curb side of a transit bus.; Standard No. 111, *Rearview Mirrors*, a copy of which is enclosed, set different requirements for buses depending on whether the gross vehicle weight rating (GVWR) is above 10,000 pounds. I believe that the GVWR of a transit bus would exceed 10,000 pounds.; Buses with a GVWR of more than 10,000 pounds must meet S7.1, whic requires buses, other than school buses, to have outside mirrors of unit magnification, each with not less than 50 square inches of reflective surface, installed with stable supports on both sides of the vehicle. These mirrors must also be located so as to provide the driver a view to the rear along both sides of the vehicle and must be adjustable both in the horizontal and vertical directions to view the rearward scene. Although the surface of your convex mirror is close to a plane (flat) surface, due to the 94.5-inch radius of curvature, it is not a unit magnification or plane mirror. Therefore, it does not meet the requirements for rearview mirrors on new buses.; A manufacturer of new transit buses could use your convex mirror on th curb side of the bus *in addition* to a unit magnification mirror which met all applicable requirements of Standard No. 111. However, a commercial business could not substitute your mirror for a complying mirror. Section 108(a)(2)(A) of the National Traffic and Motor Vehicle Safety Act prohibits any manufacturer, distributor, or dealer of motor vehicles or motor vehicle equipment, or any motor vehicle repair business from knowingly rendering inoperative any device or element of design installed on a vehicle in compliance with a safety standard. Thus, a manufacturer, distributor, dealer, or repair business could not remove a unit magnification rearview mirror, installed as original equipment in compliance with our standard, and replace that mirror with a convex mirror.; The sample of your rearview mirror, No. STS-0.253, is being returned t you under separate cover.; I hope this information is helpful to you. Sincerely, Erika Z. Jones, Chief Counsel