[§291C-85]  Signals by hand and arm orsignal lamps.  (a)  Any stop or turn signal when required herein shall begiven either by means of the hand and arm or by signal lamps, except asotherwise provided in subsection (b).

(b)  Any motor vehicle in use on a highwayshall be equipped with, and required signal shall be given by, signal lampswhen the distance from the center of the top of the steering post to the leftoutside limit of the body, cab, or load of such motor vehicle exceedstwenty-four inches, or when the distance from the center of the top of thesteering post to the rear limit of the body or load thereof exceeds fourteenfeet.  The latter measurement shall apply to any single vehicle, also to anycombination of vehicles. [L 1971, c 150, pt of §1]