Consultant Michele Ohmes answers your Americans with Disabilities Act (ADA) questions.

One of my wonderful questioners from California sent me pictures so I can discuss two of my major concerns about crossings at intersections, crosswalks, and parking lots.

Concern No. 1: The law's very first directive required detectable warnings to be the length of curb ramps. But after further study, the new design directive (Public Rights-of-Way Accessibility Guidelines 2005, Section R304.1.4) from both the Access Board and Federal Highway Administration which is supported by the Department of Justice, says the warning should be a minimum of 2 feet long and the full flat width of the ramp, landing, or blended transition.

Concern No. 2: Even though detectable warnings at curb ramps aren't intended to indicate direction, sometimes the warning and ramp's position together unintentionally confuse a visually impaired person about the crossing's path.

The following pictures should help you understand these issues:

Images A, B, and C: The detectable warnings at all three of these sidewalks extend the ramp's full length. As a wheelchair and former crutches user who deals with chronic pain, I can personally attest that it's physically excruciating to navigate these bumpy crossings.

The Access Board's Public Rights of Way subcommittee shortened the length to 2 feet because other similarly afflicted people lodged the same complaint.

Plus, a 2-foot design is less expensive.

Images B — E: Another common problem (as shown in images B and C above) is the radical change of direction that sometimes occurs between the crosswalk and the curb ramp. How is a person with severe vision limitations to know that the crosswalk lies in a totally different direction than the curb ramp dictates?

Images D and E below are examples of directional guides that a person with a cane can use to follow the crosswalk's path. Such aids cost less than an extended directional warning, giving you a positive benefit/cost ratio. Note that the pavers are (as they should be) located on the outside of the actual crosswalk instead of in the actual path.

Please seriously consider your end-users as you design, retrofit, and layout your pathways.

To understand a wheelchair user's needs, just go out with a folding chair and place yourself in the path you are designing. Or, to understand a user with visual impairments, blindfold yourself and have someone turn you about like you would in the game "pin the tail on the donkey," and then try to follow the path you are laying out for others to use.

Thanks to R. Fillmore Grefe, PE, for the pictures illustrating extended detectable warning strips and abrupt changes of direction at crosswalks.

Until next month, I hope all of you have dug yourselves out of the snow!

- Michele S. Ohmes ( is an ADA specialist who works with public works departments, facility managers, and contractors. Her design manual, ADA and Accessibility: Let's Get Practical, is available on CD-ROM through the American Public Works Association's Web site. Author's note: Michele & Associates does not render legal advice and has no enforcement authority regarding the ADA or other federal disability-rights legislation.