N.Y. Comp. Codes R. & Regs. tit. 21, § 203.6 – Traffic lanes.

(a) Slow-moving vehicles shall, under all circumstances, remain in the right-hand lane, except when lawfully passing where passing lanes exist.
(b) No vehicle shall at any time cross the dividing line between eastbound and westbound traffic.
(c) No vehicle, other than a passenger automobile, shall be permitted in the extreme left lane of a three-lane roadway on any bridge.