Section 39-21-19.1 - Vehicular hazard warning signals1. Any vehicle may be equipped with lamps for the purpose of warning the operators of other vehicles of the presence of a vehicular traffic hazard requiring the exercise of unusual care in approaching, overtaking, or passing.2. After January 1, 1980, every bus, truck, truck tractor, trailer, semitrailer, or pole trailer eighty inches [20.32 decimeters] or more in overall width or thirty feet [9.14 meters] or more in overall length must be equipped with lamps meeting the requirements of this section.3. Vehicular hazard warning signal lamps used to display warning to the front must be mounted at the same level and as widely spaced laterally as practicable, and must display simultaneously flashing white or amber lights, or any shade of color between white and amber. The lamps used to display warning to the rear must be mounted at the same level and as widely spaced laterally as practicable, and must show simultaneously flashing amber or red lights, or any shade of color between amber and red. These warning lights must be visible from a distance of not less than five hundred feet [152.4 meters] in normal sunlight.