Any truck or other motor vehicle with an open bed which is operated on any highway, road or street open for public use within the Town shall be loaded so that any loose material transported therein remains at least four inches below the walls of such open bed, measured at the front, back and sidewalls; such load may be piled higher in the center of such open bed. Loose material includes any substance which could spill, drop off or blow away from the open bed when the vehicle is operated. Loose material shall not include materials such as sand or salt which are purposely discharged from truck beds to clear roadways or improve traction and shall not include water sprayed on streets for purposes of sanitation.
(`83 Code, § 9-129)