Maryland Tire Regulations

Tire Size, Thread Depth, Width and Snow Chains Regulations

In case of declared snow emergency, chains will be required on certain designated highways. Studded snow tires are not allowed on vehicles having a registered gross weight of more than 10,000 pounds.

(a) A person may not drive a motor vehicle on any highway unless the motor vehicle is equipped with tires in safe operating condition, in accordance with requirements approved by the Administrator.

(b) A person may not drive a trailer on any highway unless the trailer is equipped with tires in safe operating condition, in accordance with requirements approved by the Administrator.

(c) The Administrator shall adopt rules of safe operating conditions capable of being employed by a police officer for visual inspection of tires maintained on vehicles, including visual comparisons with simple measuring devices. The requirements shall encompass effects on tread wear and depth of tread.

(d) If a police officer, at any time, has reasonable cause to believe that a vehicle is unsafe or equipped with tires in violation of the provisions of this section, the police officer may require the driver of the vehicle to stop and submit the vehicle tire to an inspection. If the inspection discloses the vehicle to be in violation, the officer may issue a summons for the violation.

Regrooved tires

(a) Sale of regrooved or recut tires. — A person may not sell or offer for sale any tire that has been regrooved or recut unless:

1. The tire is specifically designed to be regrooved or recut; and
2. Following such procedure, the tire complies with standards established by the United States Department of Transportation.

(b) Sale of vehicles with regrooved or recut tires. — A person may not sell or transfer any vehicle that is equipped with regrooved or recut tires, unless the tires comply with the requirements of subsection (a) of this section.

(c) Use of vehicle with regrooved or recut tires. — A person may not drive or otherwise move on any highway in this State any vehicle that is equipped with regrooved or recut tires, unless the tires comply with the requirements of subsection (a) of this section.

(d) Marking or labeling. — A person may not sell, offer for sale, or have in his possession with intent to sell, any motor vehicle tire or motorcycle tire that has had its tread regrooved without the fact being plainly shown by a marking or label in the English language on the shoulder sidewall of the tire.

Metal and other nonrubber material in contact with road surface

(a) Metal tires prohibited. — A person may not drive on any highway any motor vehicle, trailer, or semitrailer having any metal tire in contact with the roadway.

(b) Studs, cleats, etc., prohibited; exceptions. — Except as provided in subsection (c) of this section, a tire on a vehicle driven on a highway may not have on its periphery any block, stud, flange, cleat, or spike or any other protuberance of any material, other than rubber, that projects beyond the tread of the traction surface of the tire, except that:

1. It is permissible to use farm machinery with tires having protuberances that will not injure the highway;
2. It is permissible to use tire chains of reasonable proportions on any vehicle when required for safety because of snow, ice, or other conditions tending to cause a vehicle to skid;
3. It is permissible for a vehicle not registered or required to be registered in this State to use tires as described in this subsection; and
4. Except in Allegany, Carroll, Frederick, Garrett, and Washington counties, a person may not sell or offer for sale in this State any tire which is not permitted to be used in this State under this subsection.

(c) Vehicles in certain counties exempt from subsection (b). — From November 1 through March 31, owners of vehicles registered in Allegany County, Carroll County, Frederick County, Garrett County, or Washington County are exempt from the prohibition of the use of tires described in subsection (b) of this section.

(d) Special permits for operation of certain vehicles. — The State Highway Administration and local authorities in their respective jurisdictions, in their discretion, may issue special permits authorizing the operation on a highway of traction engines or tractors having movable tracks with transverse corrugations on the periphery of the movable tracks or farm tractors or other farm machinery, the operation of which on a highway otherwise would be prohibited under this section.

Spare tires

If a new Class A (passenger) or Class M (multipurpose) motor vehicle is sold in this State, the manufacturer shall equip the motor vehicle with a spare tire that conforms with the requirements in § 22-405 of this subtitle, unless:

1. The tire-wheel system of the motor vehicle provides a run-flat capability by which a partially inflated driving surface becomes available in the event of a tire failure;
2. The motor vehicle is equipped with a factory-installed temporary tire repair and inflation system; or
3. Technological improvements, consistent with applicable federal motor vehicle safety standards, become available.

Type of tires required on rear axle

Trailers. — A person may not drive any trailer weighing 73,000 pounds or more unless the rear axle of the tractor and the rear axle of the trailer are equipped with original first line tires or with recaps approved by the Administrator and the Department of State Police.

Unsafe tires

(a) Retail sale for highway use. — A person may not sell or offer for sale, at the point of final retail sale to the consumer, an unsafe tire, for use on a highway, that does not meet or exceed the requirements set forth in subsection (b) of this section or in regulations promulgated under § 22-405(c) of this subtitle.

(b) Tires considered unsafe. — A tire shall be considered unsafe if it:

1. Has tread wear indicators and the tire is worn to the point that the tread wear indicators are flush with the tread at any place on the tire;
2. Does not have tread wear indicators and the tire is worn so that less than 2/32 of an inch tread remains when measured in any groove at three locations spaced approximately equally around the outside of the tire; provided that motorcycle tires shall be allowed to be worn down to 1/32 of an inch, if measured under this paragraph;
3. Has a worn spot that exposes the cord through the tread;
4. Has tread cuts, snags, or sidewall cracks in any direction which are deep enough to expose body cords;
5. Has visible bumps, bulges, or knots indicating partial failure or separation of the tire structure;
6. Has unrepaired fabric breaks or the sidewall has damaged body cords.

Source: http://www.roads.maryland.gov/Index.aspx?PageId=242
Source: http://www.roads.maryland.gov/index.aspx?PageId=684