Bicycle Signal Heads
Bicycle signal heads are similar to conventional traffic signals, but use red, yellow, and green lenses with a stenciled bicycle icon. The 2012 AASHTO Guide for the Development of Bicycle Facilities indicates that a standard three-lens signal head with a supplemental plaque that says “BICYCLE SIGNAL” could be used. Bicycle signals should only be used in combination with an existing conventional traffic signal or hybrid beacon. Bicycle signal heads may be installed at signalized intersections to indicate bicycle signal phases and other bicycle-specific timing strategies.
A bicycle signal should be considered in the following scenarios:
- At intersections with bicycle-specific movements such as a contra-flow bicycle lane or cycle track, a bicycle signal may be necessary to indicate right-of-way to the bicyclist.
- At intersections where bicycle movements need to be separated in time from a conflicting vehicular movement, such as locations with a high volume of left- or right-turns, bicycle signals can allow for a separate bicycle phase or movement.
- At locations with high vehicle turning volumes, cyclists could benefit from a bicycle signal with a Leading Bicycle Interval (LBI), similar to a Leading Pedestrian Interval, an LBI gives bicyclists a head start at intersections by giving cyclists several seconds of green time before the concurrent vehicular movement receives the green indication. This reduces the risk of conflicts between bicyclists and turning traffic and also provides bicyclists an opportunity to make a lane change or left turn.
- At intersections with high bicycle volumes where bicyclists would otherwise follow the pedestrian indication, such as shared-use path crossings, a bicycle signal can reduce confusion. Pedestrian signal timing is inappropriate for bicyclists who travel at higher speeds, so a bicycle signal would allow bicyclists to cross legally during most of the flashing “don’t walk” interval.
- At intersections where bicyclists would normally follow the vehicular indication, a bicycle signal provides a longer clearance interval more suitable to cyclist speeds so that they do not get caught in the path of an oncoming vehicle.
Bicycle signal heads may be used to improve safety and operations at signalized intersections where bicycles require specific guidance.
- The bicycle signal shall be placed in a location clearly visible to oncoming bicyclists, who will have varying lateral positions on the bicycle facility.
- Where bicycle signals are used to separate bicycle through movements from vehicular turning movements or to provide a Leading Bicycle Interval, there should be No Right Turn on Red.
- The bicycle signal needs to have an adequate clearance interval, which is generally determined by considering intersection width and bicyclist travel speed.
- If the bicycle phase is not set to recall each cycle, bicycle signals shall be installed with appropriate detection and actuation, preferably passive (i.e. the cyclist does not have to dismount and use a push-button).
Cost will depend on the complexity and size of the intersection, but in general, costs are comparable to the installation of conventional traffic signals (e.g. controller boxes, detection devices, mast arms, etc.).