Overview
The slow-moving vehicle emblem is intended as a unique identification for, and it must be used only on, vehicles which by design move slowly (25 miles per hour or less) on the public roads. The emblem is not a clearance marker for wide machinery nor is it intended to replace required lighting or marking of slow-moving vehicles. It consists of a fluorescent yellow-orange triangle with a dark red reflective border. The yellow-orange fluorescent triangle is a highly visible color for daylight exposure. The reflective border defines the shape of the fluorescent color in daylight and creates a hollow red triangle in the path of motor vehicle headlights at night. The color film pattern, its dimensions or the backing, must not be altered to permit the use of advertising or other markings.
The material, location, mounting, etc. of the emblem must be in accordance with the American Society of Agricultural Engineers Emblem for Identifying Slow-Moving Vehicles or ASAE S276.2. The American Society of Agricultural Engineers (ASAE), which is now called the American Society of Agricultural and Biological Engineers (ASABE), is the organization that developed the standard for the SMV emblem, ASAE S276. In 1997, the standard was revised for the fifth time, signified by the last digit – ASAE S276.5 – and this revision had very significant changes. Primarily, these were requirements for newer, more advanced retro-reflective and fluorescent materials. The reflective material is the red outer border, for visibility at night, and the fluorescent material is the bright orange center, for daylight visibility.
The term “retro-reflective” means reflecting light back toward the source, such as a motor vehicle coming up behind a tractor at night. This is not a new concept, but while old reflective material scattered most of the light and reflected just a small percentage back toward the source, the latest material reflects a much higher percentage of the light. This not only makes the reflection much brighter, but also allows the SMV emblem to be seen from much farther away. The new technology uses tiny cubes or prism-like shapes inside the material instead of tiny round balls, which accounts for the greater retro-reflectivity.
New SMV emblems should be marked with ASAE S276.5 or a later revision, such as S276.6 or S276.7. Typically, the bottom red reflective border will carry the name of the manufacturer and the standard it complies to. Older SMV emblems may either be unmarked, or marked with an earlier version of the standard, like S276.3. The newer SMV emblems always will have the standard marked S276.5 or newer. The lighting and marking requirements for agricultural equipment on highways are different from state to state, but state legislation often references the content of ASABE standards.