To help ensure that pedestrians have adequate time to cross at actuated signals, they need to
press the pedestrian pushbutton
and then start crossing when the WALK signal is on.
If they cross during a green signal without being assured of a pedestrian phase
(WALK signal plus Flashing DON'T WALK signal),
they risk being in the middle of the street when the traffic on that street gets the green signal.
More about this key principle is in the section
"Strategies for Visually Impaired Pedestrians at Modern Signals."
for this section.