|FHWA Policy Memorandums|
This figure shows an example of a two-stage bicycle turn box installed at an intersection where use of the box is mandatory. For purposes of this description, it is assumed that north is upward in the figure.
The northbound approach is comprised of three through lanes, a bicycle lane, and a right-turn lane. The cross street has two lanes, one in each direction. A two-stage bicycle turn box is located on the east side of the intersection, in front of the westbound approach. Green-colored pavement is installed in the two-stage bicycle turn box. The two-stage bicycle turn box is located outside the paths of all northbound moving traffic, and a NO TURN ON RED (R10-11 Series) sign is provided for westbound traffic so that turning traffic will not conflict with queued bicyclists in the two-stage bicycle turn box. Northbound left turns are prohibited with R3-2 signs shown to northbound traffic. On the northbound approach to the intersection, ALL TURNS FROM BIKE LANE (R9-23) signing is provided both at the intersection and in advance of the intersection. There is also RIGHT LANE MUST TURN RIGHT (R3-7R) referring to the northbound right-turn lane. On the far side of the intersection, a LEFT TURN MUST USE TURN BOX (R9-23b) sign is provided with the arrow on the sign indicating the location of the two-stage bicycle turn box.
United States Department of Transportation - Federal Highway Administration