The exception is for such things as geographical information system clickable maps . Using row and column headers becomes crucial when a table is larger than two columns or two rows. Without the headers, assistive technology such as reader software can only recite the table contents with no reference to what that column or row pertains to. Markup shall be used to associate data cells and header cells for data tables that have two or more logical levels of row or column headers. Frames Frames shall be titled with text that facilitates frame identification and navigation.
Frames present unique obstacles to users of reader software.
Content developers should refrain from an overuse of time-sequenced elements. A text-only page, with equivalent information or functionality , shall be provided to make a web site comply with the provisions of this part, when compliance cannot be accomplished in any other way. The content of the text-only page shall be updated whenever the primary page changes. Content developers should only resort to alternative pages when other solutions fail . Other options include ensuring that dynamic content and refreshes can be made or are accessible.