Specifically, regulations for Web site accessability state, "Directions and cues for electronic forms must be readable with tools such as screen readers; all information conveyed with color must be available without color; users must be alerted to timed responses and given a chance to signal they need more time to complete a function; pictures and graphics must be tagged with text descriptions."
You may find helpful an article entitled, Making Your Web Site Accessible to the Blind, written by Curtis Chong, Director of Technology, National Federation of the Blind.Be sure you read the other accessibility articles on evolt.org.
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