Rhode Island Tire Regulations

§ 31-23-20 Protuberances on tires. – No tires on a vehicle moved on a highway shall have on its periphery any block, flange, cleat, or pointed spike or other protuberance of any material other than rubber which projects beyond the tread of the traction surface of the tire except that:

(1) It shall be permissible to use tires with flat-headed studs projecting one-sixteenth inch ( 1/16") or less beyond the tread of the traction surface from the fifteenth day of November to the first day of April;

(2) It shall be permissible to use farm machinery with tires having protuberances which will not injure the highway; and

(3) It shall be permissible to use tire chains of reasonable proportions upon any vehicle when required for safety because of snow, ice, or other conditions tending to cause a vehicle to skid.

(4) Violations of this section are subject to fines enumerated in § 31-41.1-4.

31-23-45 Tire treads. – (a) No tire on a vehicle moved on a highway shall have on its periphery less than two thirty-seconds (2/32) of an inch of tread depth. The administrator of the division of motor vehicles is authorized to remove from a highway any vehicle not conforming to this requirement and shall suspend the registration of the motor vehicle until it is made to conform to the requirements of this section.

http://webserver.rilin.state.ri.us/Statutes/TITLE31/31-23/31-23-20.HTM