Whenever any roadway has been divided into two or more clearly marked lanes for traffic, or whenever traffic is lawfully moving in two or more substantially continuous lines in the same direction, the following rules apply:
(a) A vehicle shall be driven, as nearly as is practicable, entirely within a single lane or line of traffic and shall not be moved from such lane or line until the driver has first ascertained that such movement can be made with safety.
(b) Upon a roadway which is divided into three lanes and provides for two-way movement of traffic, a vehicle shall not be driven in the center lane except when overtaking and passing another vehicle where the roadway is clearly visible and such center lane is clear of traffic within a safe distance, or when preparing for a left turn, or where such center lane is at the time allocated exclusively to traffic moving in the direction the vehicle is proceeding and is posted with signs to give notice of such allocation.
(c) Officials signs may be erected directing specified traffic to use a designated lane or designating those lanes to be used by traffic moving in a particular direction regardless of the center of the roadway, and drivers of vehicles shall obey the directions of such signs.
(d) Official traffic control devices may be installed prohibiting the changing of lanes on sections of roadway and drivers of vehicles shall obey the directions of every such device.
(ORC 4511.33)