Accessbile Pedestrian Signals (APS)
Accessible pedestrian signals (APSs) supplement pedestrian push button signal indications with audible and/or vibrotactile information. These accommodations include directly audible or transmitted tones, speech messages, Talking Signs, and vibrating surfaces. They are intended make real-time pedestrian signal information accessible to pedestrians who are visual-impaired.
Many different technologies exist. Newer signal types have a quiet, slowly repeating locator tone that indicates to approaching pedestrians that they must push a button to get a WALK signal and indicates the location of the push button. Directly audible or transmitted speech messages can identify the location of the intersection and the specific crosswalk controlled by that push button. A vibrating arrow at the push button can also be used to supplement the audible signals.
Detectable Warning Surfaces
Truncated domes (detectable warnings) are an Americans with Disabilities Act (ADA) requirement in the current Americans with Disabilities Act Accessibility Guidelines (ADAAG) for the use of detecting the boundary between the sidewalk and the street. Truncated domes are the only detectable warnings allowed by ADAAG. Truncated domes are a unique design and have proven to be the most detectable surface. They are designed to help individuals with visual impairments feel the raised, truncated domes with their long mobility cane.