While assistive technology does not yet widely support the "title" attribute, we recommend
including this attribute in web pages using frames.
Example: ADA Technical Assistance Program The use of frames with No Frames Link
www.adata.org
(j) Pages shall be designed to avoid causing the screen to flicker with a frequency
greater than 2 Hz and lower than 55 Hz.
Why is this provision necessary?
This provision is necessary because some individuals with photosensitive epilepsy can have a
seizure triggered by displays that flicker, flash, or blink, particularly if the flash has a high
intensity and is within certain frequency ranges. The 2 Hz limit was chosen to be consistent with
proposed revisions to the ADA Accessibility Guidelines which, in turn, are being harmonized
with the International Code Council (ICC)/ANSI A117 standard, "Accessible and Usable
Buildings and Facilities", ICC/ANSI A117.1 1998 which references a 2 Hz limit. An upper limit
was identified at 55 Hz.
How can flashing or flickering elements be identified?
Flashing or flickering elements are usually added through technologies such as animated gif s,
Java applets, or third party plug ins or applications. Java applets and third party plug ins can be
identified by the presence of
download in a single file (like ordinary image files), but have content that changes over short
periods of time. Like other images, however, they are usually incorporated through the use of
the ![]()
tag.
(k) A text only page, with equivalent information or functionality, shall be provided to
make a web site comply with the provisions of these standards, when compliance cannot
be accomplished in any other way. The content of the text only page shall be updated
whenever the primary page changes.
What must a text only page contain to comply with this provision?
Text only pages must contain equivalent information or functionality as the primary pages. Also,
the text only page shall be updated whenever the primary page changes.
Example: Disability.gov displays a text only page on home page
HTML source code:
Link:
http://www.disability.gov/
National GACC Website and GACC Website Template
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Implementation Guidelines