Wikipedia:WikiProject Accessibility/Manual of Style draft

After a discussion on Wikipedia talk:Manual of Style (accessibility), it became clear that great changes needs to be prepared on a dedicated subpage.

Each section is a draft for a change. They have several possible status. A draft is ready to be implemented in Wikipedia talk:Manual of Style (accessibility) once it's marked as "reviewed by an accessibility expert and ready for implementation".

Criteria on this page are prioritized according to impact (W3C's accessibility level of priorities: A, AA or AAA) and degree of feasibility (with MediaWiki's syntax and the burden it places on users).

Data tables

Status: Complete. Reviewed by an accessibility expert.

Priority: high (A accessibility level)
Difficulty: easy (blend in nicely with editorial habits)

{| 
|+ [caption text]
|-
! scope="col" | [column header 1]
! scope="col" | [column header 2]
! scope="col" | [column header 3]
|-
! scope="row" | [row header 1]
| [normal cell 1,2] || [normal cell 1,3]
|-
! scope="row" | [row header 2]
| [normal cell 2,2] || [normal cell 2,3]
...
|}

Caption ( |+ ): A caption is a table's title, describing its nature.^{[WCAG-TECH 1]}
Row & column headers ( ! ): Like the caption, these help present the information in a logical structure to visitors.^{[WCAG-TECH 2]} The headers help screen readers render header information about data cells. For example, header information is spoken prior to the cell data, or header information is provided on request.^[1]
Scope of headers ( ! scope="col" | and ! scope="row" | ): This clearly identifies headers as either row headers or column headers. Headers can now be associated to corresponding cells.^{[WCAG-TECH 3]}

Wikipedia:WikiProject Accessibility/Manual of Style draft/Data tables tutorial provides detailed requirements:

Correct table captions
Correct headers structure
Images and color
Avoiding nested tables

Layout tables

Statuts : under construction

Bad example

From S.M.A.R.T.. This layout table uses a table header, which indicates a data table where it is a layout table. Also, it uses a poorly contrasted icon without alt text.

Legend
	Higher raw value is better		Lower raw value is better
Critical: red colored row		Potential indicators of imminent electromechanical failure

Good example

Icons with improved contrast, alt text and no link. The warning information given by the red row is now also textually provided by the warning icon thanks to alt=warning.