When a roadway has been divided into clearly marked lanes for traffic, drivers of vehicles
shall obey the following regulations:
a. A vehicle shall normally be driven in the lane nearest the right-hand edge or curb of the
roadway when that lane is available for travel, except when overtaking another vehicle or in
preparation for a left turn.
b. A vehicle shall be driven as nearly as practicable entirely within a single lane and shall
not be moved from that lane until the driver has first ascertained that the movement can be
made with safety.
c. Upon a highway which is divided into 3 lanes, a vehicle shall not be driven in the center
lane except when overtaking or passing another vehicle or in preparation for a left turn or unless
the center lane is at the time allocated for traffic moving in the direction the vehicle is
proceeding and is signposted to give notice of that allocation.
d. The State Highway Commissioner may by regulation or local authorities may by
resolution or ordinance with respect to highways under their jurisdiction designate right-hand
lanes for slow moving traffic and inside lanes for traffic moving at the speed designated for the
district as provided under this chapter, and when the lanes are signposted or marked to give
notice of the designation a vehicle may be driven in any lane allocated to traffic moving in the
direction in which it is proceeding, but when traveling within the inside lanes the vehicle shall be
driven at approximately the speed authorized in such lanes and speed shall not be decreased
unnecessarily so as to block, hinder or retard traffic.
e. When such roadway had been divided in such a manner that there are three or more
lanes for traffic in any one direction, no truck of 10,000 pounds registered gross weight or over
shall be driven in the farthest left-hand lane, except:
(1) when and to the extent necessary to prepare for a left turn; a truck may be driven in the
farthest left lane for up to one mile to prepare for a left hand turn as authorized under this
(2) when necessary to enter or leave such roadway by entrance or exit to or from the left
lane; a truck may be driven in the farthest left lane for up to one mile to prepare to enter or leave
the roadway as authorized under this paragraph;
(3) when reasonably necessary in response to emergency conditions; for the purposes of
this paragraph, “emergency conditions” shall include, but not be limited to: poor visibility, snow,
accidents, or the presence of emergency vehicles.
amended 1951, c.23, s.47; 1968, c.432; 2013, c.86, s.1.