Under 49 CFR 571.111, a school bus cross view mirror with an average radius of curvature of less than 889 mm must carry a label visible to the seated driver. What does that label tell the driver?

Explanation

The label states that the cross view mirrors are to be used to view pedestrians while the bus is stopped, that they are not to be used to view traffic while the bus is moving, and that images in such mirrors do not accurately show another vehicle's location. 49 CFR 571.111 (FMVSS No. 111) S9.3(c) prescribes those words exactly and requires them to be printed clearly and conspicuously where the seated driver can read them, on any school bus cross view mirror installed under S9.3(a) whose average radius of curvature is less than 889 mm. Read it for what it is: a labeling requirement addressed to the manufacturer, whose content happens to be an instruction to the driver. The standard does not itself create a federal offense of glancing at a cross view mirror under way, and the operating rules that actually govern school bus mirror use are state law, consistent with the way 49 CFR 383.123(a)(2)(i) defers to State or Federal law for these devices. What the label does is tell the driver what the mirror is good for: finding a child in the front and side danger zones of a stationary bus, and not judging the distance of a moving vehicle on a surface that compresses distance. Each wrong option states the opposite of some part of the label, whether by making the mirror a substitute for direct vision in motion, a distance gauge for following traffic, or something to be set while driving rather than before operating the bus. Note that the separate optical point, that a convex mirror makes objects look smaller and farther away than they are, is general commercial driving knowledge covered elsewhere; what this label adds is the stopped-versus-moving distinction.

Source: 49 CFR 571.111 (FMVSS No. 111) S9.3(c)