QUAIL: Accessibility Information Library
Adjacent links that point to the same location should be merged
Example
Example
When an image is in a link, its “alt” attribute should not repeat other text in the link
Example
Link text should not begin with redundant text
Lists of links should be seperated by printable characters
Example
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Links should not open a new window without warning
Example
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The text in links should make sense out of context
Example
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Any links to a multimedia file should also include a link to a transcript
Example
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Any links to a sound file should also include a link to a transcript
Example
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Links should contain text
Example
All links must have a “title” attribute
Example
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Links should not use “javascript” in their location
Link text should be useful
The title attribute of all source a (anchor) elements describes the link destination.
Example
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The document should contain an address for the author
The document should contain a valid email address for the author
All applets should contain the same content within the body of the applet
Example
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All applets should contain a text equivalent in the “alt” attribute
Example
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All applets should provide a way for keyboard users to escape
Any user interface in an applet must be accessible
All applets do not flicker
Applets should not use color alone to communicate content
All “area” elements must have an “alt” attribute which describes the link destination
Alt text for “area” elements should replicate the text found in the image
No “area” elements should open a new window without warning
Example
Wrong
All “area” elements must have an “alt” attribute
Example
Wrong
All “area” elements which link to a sound file should also provide a link to a transcript
Example
Wrong
Pages using ARIA roles should not have orphaned content
Basefont” should not be used
The “blink” tag should not be used
Example
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The “blockquote” tag should not be used just for indentation
Example
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If long quotes are in the document, use the “blockquote” element to mark them
Example
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Contrast between active link text and background should be 5:1
Contrast between text and background should be 5:1
Contrast between link text and background should be 5:1
Body elements do not use a background image
Contrast between visited link text and background should be 5:1
The “b” (bold) element is not used
Example
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All checkboxes must have a corresponding label
All “checkbox” input elements have a label that is close
The document must be readable with styles turned off
All elements should have appropriate color contrast
The document should contain a valid “doctype” declaration
Example
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Abbreviations must be marked with an “abbr” element
Example
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Acronyms must be marked with an “acronym” element
Example
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All the document colors must be set
Auto-redirect with “meta” elements must not be used
Contrast between active link text and the background must be greater than the WAI ERT color algorithm threshold
Contrast between text and the background must be greater than the WAI ERT color algorithm threshold
Contrast between link text and the background must be greater than the WAI ERT color algorithm threshold
Contrast between visited link text and the background must be greater than the WAI ERT color algorithm threshold
Content should be readable without style sheets
The document should have a title element
Example
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All element “id” attributes must be unique
Example
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The document should be written to the target audience and read clearly
The document’s language attribute should be a standard code
Example
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The document must have a “lang” attribute
Example
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Meta” elements must not be used to refresh the content of a page
Example
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Reading direction of text is correctly marked
The page uses a strict doctype
The title describes the document
Example
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The document title should not be placeholder text
Example
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The document title should be short
Example
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The document should not have an empty title
Example
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Document must validate to the doctype
Visual lists of items are marked using ordered or unordered lists
Example
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Any words or phrases which are not the document’s primary language should be marked
Example
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All “embed” elements have an associated “noembed” element
Example
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Embed” elements must have an “alt” attribute
Example
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Embed” elements cannot have an empty “alt” attribute
Example
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All embed elements should provide a way for keyboard users to escape
Emoticons should not be used excessively
Example
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All “file” input elements have a corresponding label
All “file” input elements have a label that is close
Font” elements should not be used
Deleting items using a form should be reversable
Forms offer the user a way to check the results of their form before performing an irrevokable action
Form error messages should assist in solving errors
Input items which are required are marked as so in the label element
<h4>Examples</h4>Wrong
Frames are not used
Complex framesets should contain a “longdesc” attribute
Example
Wrong
The source for each frame is accessible content.
All “frame” elemetns should have a “title” attribute that describes the purpose of the frame
Example
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Frames cannot have empty “title” attributes
Frames cannot have “title” attributes that are just placeholder text
All “frame” elements should have a “title” attribute
Example
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The “frameset” element should not be used
All framesets should contain a noframes section
Example
Wrong
The header following an h1 is h1 or h2
All h1 elements are not used for formatting
Example
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The header following an h2 is h1, h2 or h3
All h2 elements are not used for formatting
Example
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The header following an h3 is h1, h2, h3 or h4
All h3 elements are not used for formatting
Example
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The header following an h4 is h1, h2, h3, h4 or h5
All h4 elements are not used for formatting
Example
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The header following an h5 is h6 or any header less than h6
All h5 elements are not used for formatting
Example
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All h6 elements are not used for formatting
Example
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All headers should contain readable text
Use headers to mark the beginning of each section
The “i” (italic) element is not used
Example
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Inline frames (“iframes”) should not have a “longdesc” attribute
All links in a server-side map should have duplicate links available in the document
If an image is purely decorative, the “alt” text must be empty
Any image within a link must have “alt” text the describes the link destination
Example
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Image “alt” attributes should not be the same as the filename
Check that any text within an image is also in the “alt” attribute
Image Alt text is short
Example
Wrong
An image within a link cannot have an empty “alt” attribute if there is no other text within the link
Example
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Images should not have a simple placeholder text as an “alt” attribute
<ul><li>nbsp</li><li>&nbsp;</li><li>spacer</li><li>image</li><li>img</li><li>photo</li></ul>Example
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Unless the image files are the same, no image should contain redundant alt text
Example
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Any animated GIF should not flicker
Image elements must have an “alt” attribute
Example
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A “longdesc” attribute is required for any image where additional information not in the “alt” attribute is required
Example
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Images that are important should not have a purely white-space “alt” attribute
All links within a client-side image are duplicated elsewhere in the document
Example
Wrong
An image with a “longdesc” attribute should have a corresponding description link
Any non-decorative images should have a non-empty “alt” attribute
Example
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For any image, the “alt” text cannot refer to color alone
Server-side image maps should not be used
Images should not have a “title” attribute
Example
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Any image with an “ismap” attribute have a valid “usemap” attribute
Images which contain math equations should provide equivalent MathML
Example
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All “checkbox” input elements require a valid “tabindex” attribute
Logical groups of check boxes should be grouped with a “fieldset
Example
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An “input” element should not use color alone
Input elements which are not images should not have an “alt” attribute
All “file” input elements require a valid “tabindex” attribute
All “input” elements with a type of “image” must have an “alt” attribute that describes the function of the input
All “input” elements with a type of “image” must have an “alt” attribute which is not the same as the filename
All “input” elements with a type of “image” must have an “alt” attribute which is not placeholder text
All “input” elements with a type of “image” must have an “alt” attribute which is as short as possible
The “alt” text for input “image” submit buttons must not be filler text
Example
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All “input” elements with a type of “image” must have an “alt” attribute
Example
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The “alt” text for input “image” buttons must be the same as text inside the image
All “password” input elements require a valid “tabindex” attribute
All “radio” input elements require a valid “tabindex” attribute
All input elements, type of “submit
All “input” elements should have a corresponding “label
All “text” input elements require a valid “tabindex” attribute
All “input” elements of type “text” must have a default text
Example
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Text” input elements require a non-whitespace default text
Example
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Label” elements should not contain an input element
Example
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Every form input must have only one label
Example
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Labels must contain text
Example
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All labels should be associated with an input
All “legend” elements must describe the group of choices
Example
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Legend” text must not contain just whitespace
Example
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Legend” text must not contain placeholder text like “form” or “field
Example
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Use a “link” element for alternate content
Example
Document uses link element to describe navigation if it is within a collection.
Lists should not be used for formatting
Example
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The “marquee” tag should not be used
Example
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Menu” elements should not be used for formattin
Example
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Noembed” elements must be the same content as their “embed” element
Example
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All “noframes” elements should contain the text content from all frames
When objects are disabled, content should still be available
Example
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Objects do not flicker
Objects must not use color to communicate alone
Interfaces within objects must be accessible
Objects which reference multimedia files should also provide a link to a transcript
Example
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Objects must contain their text equivalents
Example
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Every object should contain an “embed” element
Example
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Objects should have a title attribute
Example
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Objects must not have an empty title attribute
Example
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All objects should provide a way for keyboard users to escape
An object might require a long description
Example
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The text equivalents of an object should update if the object changes
Content within an “object” element should be usable with objects disabled
Objects with “classid” attributes should change their text if the content of the object changes
Paragraphs must not be used for headers
Example
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All password input elements should have a corresponding label
All “password” input elements have a label that is close
Pre” elements should not be used for tabular data
All “radio” input elements have a corresponding label
All “radio” input elements have a label that is close
All radio button groups are marked using fieldset and legend elements.
Content on the page should still be available if scripts are disabled
Scripts should have a corresponding “noscript” element
Example
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If an element has an “onclick” attribute
Any element with an “ondblclick” attribute shoul have a keyboard-related action as well
If an element has a “mousedown” attribute
Any element with an “onmousemove” attribute shoul have a keyboard-related action as well
If an element has a “onmouseout” attribute
If an element has an “onmouseover” attribute
If an element has an “onmouseup” attribute
The user interface for scripts should be accessible
Scripts should not cause the screen to flicker
The interface in scripts should not use color alone
Select” elemetns must not contain an “onchange” attribute
Example
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All select elements have an explicitly associated label.
Select jump menus should jump on button press, not on state change
Form select elements should use optgroups for long selections
Websites must have a site map
A “skip to content” link should exist as one of the first links on the page
Inline SVG should use Title elements
The tab order of a document is logical
Captions should identify their table
Complex tables should have a summary
Data tables should contain “th” elements
Example
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Table header lables must be terse
Mark up the areas of tables using “thead
Layout tables should not contain “th” elements
Example
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All tables used for layout have no “caption” element
Example
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All tables used for layout have no summary or an empty summary
All tables used for layout should make sense when removed
Table summaries should describe the navigation and structure of the table
Table “summary” elements should not duplicate the “caption” element
All data tables should have a summary
Example
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All data tables should have an adequate summary
Example
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Group columns using “colgroup” or “col” elements
Table headers over 20 characters should provide an “abbr” attribute
<h4>Examples</h4>Wrong
Right
Data tables should contain a “caption” element if not described elsewhere
Example
Data tables should use scoped headers for rows with headers
Example
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Data tables with multiple headers should use the “scope” attribute
Complex data tables should provide “id” attributes to headers
All tabular information should use a table
The text size is not less than 9 pixels high
All textareas should have a corresponding label
All textareas should have a label that is close to it
Example
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All video tags must provide captions
All linked or embedded videos need captions
QUAIL: Accessibility Information Library
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Objects do not flicker
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Objects do not flicker
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The content within an <code>object tag must not flicker.
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