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Appendix D: Glossary of Terms

Academy for Certification of Vision Rehabilitation and Education Professionals (ACVREP): The body which provides certification of vision-related rehabilitation professionals, including Certified Orientation and Mobility Specialists (COMS). The professional certification of O&M Specialists, which is provided currently by ACVREP, was first established over 30 years ago. Originally, O&M certification was administered through the Association for Education and Rehabilitation of the Blind and Visually Impaired AER, and it’s predecessor, The American Association of Workers for the Blind (AAWB), starting in 1968. In January 2000, certification of O&M specialists was taken on by the ACVREP, which is an independent and autonomous legal certification body governed by a volunteer Board of Directors. Orientation and mobility specialists certified by ACVREP use the acronym COMS.

Accessible Pedestrian Signal (APS): A device that communicates information about pedestrian timing in nonvisual format such as audible tones, verbal messages, and/or vibrating surfaces (MUTCD, Section 4A.02). An alternative definition, A device that communicates information about the WALK phase in audible and vibrotactile formats, can be found in Draft PROWAG, R105.5.

Audible beaconing: The use of an audible signal in such a way that pedestrians who are blind or visually impaired can use hearing to home in on the signal from the opposite corner as they cross the street. The ascending or descending audible tone is intended to provide directional orientation.

Certified Orientation and Mobility Specialist (COMS): Certified Orientation and Mobility Specialists (COMS) provide sequential instruction to individuals with visual impairment in the use of their remaining senses to determine their position within the environment and in techniques for safe movement from one place to another.

Controller Assembly (CA): A complete electrical device mounted in a cabinet for controlling the operation of a highway traffic signal.

Cycle: The time required for one complete sequence of light changes (phases)

Detectable warnings (DW): is a standardized surface of truncated domes built into or applied to walking surfaces or other elements to warn visually impaired persons of hazards in the path of travel.

Interval: A portion of the signal cycle during which the signal indications remain unchanged, for example, the pedestrian walk interval, the pedestrian clearance interval

Manual on Uniform Traffic Control Devices (MUTCD): The reference publication that defines the standards used by road managers nationwide to install and maintain traffic control devices on all public streets, highways, bikeways, and private roads open to public traffic. The MUTCD is published by the Federal Highway Administration (FHWA) under 23 Code of Federal Regulations (CFR), Part 655, Subpart F.

Ped button: The pushbutton that you push (also called the ped detector), which is usually on the same pole as the pedhead, but which may be difficult to locate at some intersections

Pedcall: What happens when you push the button. Signals the signal controller box that there is a pedestrian at the intersection.

Pedhead: The "walk/don't walk" signal, usually a square box type signal on a pole, aligned to be visible to sighted pedestrians from the crosswalk

Ped Phase: What you get as a result of pushing the button (the ped phase is designed to provide a long enough time to walk, rather than drive, across the intersection).

Phase: The portion of a signal cycle allocated to any combination of one or more traffic movements receiving the right of way at the same time, for example, the westbound phase, the pedestrian phase

Public Rights of Way Access Guidelines (PROWAG): draft guidelines, for public rights-of-way which when adopted, will address, various issues, including access for blind pedestrians at street crossings, wheelchair access to on-street parking, and various accessibility constraints posed by space limitations, roadway design practices, slope, and terrain.

Roundabout: A type of circular junction in which road traffic must travel counter-clockwise in one direction around a central island.

Scramble light: A pedestrian crossing system that stops all vehicular traffic and allows pedestrians to cross an intersection in every direction, including diagonally, at the same time.

Split: Percentage of the cycle length allocated to each of the various phases.
Traffic engineer(TE): An engineer who plans and monitors the geometric design and traffic operations of roads, streets, motorways, their networks and their relationships with all modes of transportation for the safe, efficient and convenient movement of people and goods.