Prepare to Stop When Flashing (PTSWF) Signs
Ohio Department of Transportation is reviewing the statewide use of “Prepare to
Stop When Flashing” signs historically used to alert drivers that a signal is
turning red. The signs are being
replaced with new technology that can detect the speed of approaching vehicles
and adjust the signal to prevent red-light running and crashes.
statewide review of the signs found that drivers often speed up instead of
slowing down, increasing the number and severity of crashes at intersections.
has seen a significant reduction in crashes at 14 intersections where the signs
were removed within the past two years.
The average crash reductions included a 23% reduction in total crashes; 35%
reduction in serious crashes; 42% reduction in angle crashes; and 50% reduction
in red-light running crashes.
states are reexamining the practice of using the warning signs, which were
often installed at isolated intersections where motorists are traveling at high
speeds and not expecting to stop. They
are also used at locations where signals are difficult to see because of
of the signs will be replaced with new, safer technology called dilemma zone
detectors. These detectors use radar
technology to monitor the speed of approaching vehicles and extend the signal
green time if a motorist cannot safely stop for the red light. For more information please download this file.
is also adding florescent yellow borders to many signals to improve visibility
at night and longer distances.
However, not every warning sign will be removed. Each location will be evaluated (how), and
some signs may be retained, especially in areas where geography makes it
difficult to see the signals at a distance.