Federal Motor Vehicle Safety Standard 111 is a specification pertaining to the rear vision parts of a vehicle. This federal standard outlines important safety requirements as it relates to automotive mirrors. FMVSS 111 specifies the required range of vision that the driver must achieve utilizing rear vision products. These ranges are both horizontal and vertical angles from the side and rear of the vehicle. In addition, FMVSS 111 states that rear vision products “…shall have an average reflectance of at least 35 percent” (OEM mirrors are typically between 40% and 60% reflective). This part of the spec is achieved through the use of special first-surface chrome glass. If there was a convex part on the vehicle originally, it should be replaced with a convex part etched with the proper “OBJECTS APPEAR…” statement. Household mirror should NOT be used in automotive mirror applications.
Our Interpretation of the Standard:
Passenger vehicles must have an inside mirror along with a driver’s side mirror for rear viewing. If viewing from an inside mirror is impossible; example a cube van, then the vehicle must have a passenger side mirror along with a driver’s side mirror.
The passenger side mirror is optional as long as there is a field of vision from using an inside rearview mirror. The passenger side mirror can be flat or convex. If it is convex, the insignia “Objects are closer than they appear” must be inscribed on the face.
The key function for rearview mirrors is to maximize the field of vision of the area behind the driver. The convex mirror was designed to increase that field of view. The federal law does not specifically dictate usage of convex mirror for passenger side viewing; however, to be on the safe side, if a convex mirror part was originally used then convex should be reinstalled to maintain the maximum field of vision.