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. A tire shall be considered unsafe if it: 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; 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; Has a worn spot that exposes the cord through the tread; Has tread cuts, snags, or sidewall cracks in any direction which are deep enough to expose body cords; Has visible bumps, bulges, or knots indicating partial failure or separation of the tire structure; Has unrepaired fabric breaks or the sidewall has damaged body cords; Has been regrooved or recut except as authorized in § 22-405.1 of this subtitle; or Is marked: For farm use only; For off-highway use only; or For racing use only. A tire failing to meet the requirements of subsection (b) of this section may be sold for off-highway use only if the tire has permanently inscribed on its sidewall the letters “OH” at least 3/4 of an inch in height.