Whenever any roadway has been divided into two or more clearly marked lanes for traffic, the following requirements in addition to all others consistent herewith shall apply.

1. 1. A vehicle shall be driven as nearly as practicable entirely within a single lane.
2. 2. A vehicle shall not be moved from the lane until the driver has first ascertained that the movement can be made with safety and then given a signal, not less than the last one hundred (100) feet traveled by the vehicle, of his intention to change lanes.
3. 3. Upon a roadway which is divided into three lanes, a vehicle shall not be driven in the center lane except when overtaking and passing another vehicle where the roadway is clearly visible and the center lane is clear of traffic within a safe distance, or in preparation for a left turn or where the center lane is at the time allocated exclusively to traffic moving in the direction the vehicle is proceeding and is signposted to give notice of the allocation.
4. 4. Upon a roadway which is divided into four or more lanes, a vehicle proceeding at less than the maximum posted speed, except when reduced speed is necessary for safe operation, shall not impede the normal flow of traffic by driving in the left lane. The vehicle shall be driven in the right-hand lane except when overtaking and passing another vehicle proceeding in the same direction or when preparing for a left turn at an intersection or into a private road or driveway.
5. 5. Official signs may be erected directing slow-moving 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 every such sign.

Laws 1961, p. 377, § 11-309; Amended by Laws 1984, HB 1844, c. 47, § 1, eff. November 1, 1984; Amended by Laws 2002, HB 2302, c. 397, § 22, eff. November 1, 2002 (superseded document available); Amended by Laws 2005, HB 1993, c. 394, § 11, eff. June 6, 2005 (superseded document available).