Section 39-21-40 - Restrictions as to tire equipment1. Every solid rubber tire on a vehicle must have rubber on its entire traction surface at least one inch [2.54 centimeters] thick above the edge of the flange of the entire periphery.2. No person may operate or move on any highway any motor vehicle, trailer, or semitrailer having any metal tire in contact with the roadway.3. No tire on a vehicle moved on a highway may have on its periphery any block, stud, flange, cleat, or spike or any other protuberance of any material other than rubber which projects beyond the tread of the traction surface of the tire, except that it is permissible to use farm machinery with tires having protuberances which will not injure the highway, and except also that it is permissible to use tire chains of reasonable proportions. It is also permissible to use, from October fifteenth to April fifteenth, pneumatic tires which have metal studs which do not project more than one-sixteenth of an inch [1.59 millimeters] beyond the tread of the traction surface of the tire, except that it is permissible to use such tires on schoolbuses at any time during the year.