In addition to the substantial installation costs, pedestrian signals consume a significant amount of electrical power at a typical intersection. If the vehicular indications can safely accommodate pedestrian traffic, then there is no justification for spending scarce resources to install elaborate pedestrian controls. At some intersections it may be that only pedestrian detectors need to be installed. Where pedestrian volumes are low and pedestrian signals are not needed, a pedestrian detector can be used to extend the vehicular green, if it would otherwise be too short for a pedestrian to cross. However, they is no guarantee of safety.
Pedestrians still have to exercise sound judgment when crossing a roadway.
This will guarantee adequate crossing time. This will insure that adequate crossing time will be available. Pushing the detector when the signal is already green will not cause the green time to be extended during that particular green interval. The next green interval will, however, be extended. WALK - there is still adequate time to finish crossing before opposing traffic is released.