Accessibility Checking for Large Sites

A document’s accesskey attribute values must all be distinct. Or, to put it another way, accesskeys must not be used more than once to protect keyboard users from unpleasant surprises.

When a document’s accesskey attribute value is supplied, users can quickly activate or switch the focus to a particular element by hitting the designated key (often in tandem with the alt key). The page becomes less accessible as a result of duplicating the values for the accesskey attribute.

Make sure the value of each defined accesskey is distinct and does not interfere with any screen reader or default browser shortcut keys.

Users who must use alternative keyboards or input devices serving as keyboard emulators, users who have problems tracking a pointer, or users who are blind or have low eyesight and cannot employ eye-hand coordination-required devices like mice, cannot operate the content.

What this Accessibility Rule Checks

Makes certain that every element on the page with an accesskey attribute has a different value.

The destination, purpose, function, or action of an ARIA command element must be made clear in understandable text for screen reader users.

The function of items with the roles link, button, or menuitem that lack an accessible name cannot be understood by screen reader users.

What this Accessibility Rule Checks

Verifies that all elements with the roles link, button, or menuitem have a clear, understandable name.

ARIA attributes must be used as specified for the element’s role.

Using ARIA attributes on elements where they are not expected can result in unpredictable behavior for assistive technologies. This can lead to a poor user experience for people with disabilities who rely on these technologies. It is important to follow the ARIA specification to ensure that assistive technologies can properly interpret and communicate the intended meaning of the content.

Some ARIA attributes are only allowed on an element under certain conditions. Different attributes have different limitations to them:

aria-checked: This should not be used on an HTML input element with type=”checkbox”. Such elements have a checked state determined by the browser. Browsers should ignore aria-checked in this scenario. Because browsers do this inconsistently, a difference between the native checkbox state and the aria-checked value will result in differences between screen readers and other assistive technologies.

The aria-posinset, aria-setsize, aria-expanded, and aria-level attributes are conditional when used on a row. This can be either tr element, or an element with role="row". These attributes can only be used when the row is part of treegrid. When used inside a table or grid, these attributes have no function, and could result in unpredictable behavior from screen readers and other assistive technologies.

What this Accessibility Rule Checks

Check that ARIA attributes are not used in a way that their role describes authors should not, or must not do. I.e the use of this ARIA attribute is conditional.

For screen reader users, Aria dialog items must include intelligible language that specifies the destination, purpose, function, or action in detail.

Elements with role="dialog" or role="alertdialog" that lack an accessible name cannot be understood by screen reader users.

What this Accessibility Rule Checks

Verifies that all objects with the role="dialog" or role="alertdialog" attribute have a clear, understandable name.

This rule determines whether or not aria-hidden elements contain focusable elements.

Using the property aria-hidden="true" on an element removes the element and all of its child nodes from the accessibility API, rendering the element fully unavailable to screen readers and other assistive technology.

aria-hidden may be used with extreme discretion to hide visibly displayed content from assistive technologies if the act of hiding this content is meant to enhance the experience of assistive technology users by reducing redundant or superfluous content.

If aria-hidden is employed to hide material from screen readers, the same or equal meaning and functionality must be made available to assistive technologies.

Using aria-hidden="false" on content that is a descendant of an element that is hidden using aria-hidden="true" will not reveal that content to the accessibility API, nor will it be accessible to screen readers or other assistive technology.

The rule applies to any element whose aria-hidden attribute value is true.

By adding aria-hidden="true" to an element, authors assure that assistive technologies will disregard the element. This can be used to hide aesthetic elements, such as icon typefaces, that are not intended to be read by assistive technologies.

A focusable element with aria-hidden="true" is disregarded as part of the reading order, but is still part of the focus order, making it unclear if it is visible or hidden.

What this Accessibility Rule Checks

For all user interface components, including form elements, links, and script-generated components, the name and role can be identified programmatically; user-specified states, properties, and values can be set programmatically; and user agents, including assistive technologies, are notified of changes.

Ensures every ARIA input field has an accessible name.

This rule ensures that each ARIA input field has a name that is accessible.

There must be accessible names for the following input field roles:

• combobox
• listbox
• searchbox
• slider
• spinbutton
• textbox

What this Accessibility Rule Checks

The names of ARIA input fields must be accessible.

For screen reader users, aria meter elements must have legible language that defines the destination, function, or action.

Users of screen readers are unable to determine the function of items with role="meter" but no accessible name.

What this Accessibility Rule Checks

Checks that all items with role="meter" have a distinguishable, accessible name.

For screen reader users, Aria progressbar items must include understandable language that specifies the destination, purpose, or action.

Users of screen readers are unable to determine the purpose of items with the role="progressbar" attribute that lack an accessible name.

What this Accessibility Rule Checks

Checks that all items with role="progressbar" have a distinguishable, accessible name.

Elements must only use permitted ARIA attributes.

Using ARIA attributes in roles where they are prohibited can mean that important information is not communicated to users of assistive technologies. Assistive technologies may also attempt to compensate for the issue, resulting in inconsistent and confusing behavior of these tools.

Not all ARIA role-attribute combinations are valid. This Rule checks that noe of the attributes used with a particular role are listed as “prohibited” for that role in the latest version of WAI-ARIA.

The aria-label and aria-labelledby attributes are prohibited on presentation and none roles, as well as on text-like roles such as code, insertion, strong, etc.

What this Accessibility Rule Checks

Checks that each ARIA attribute used is not described as prohibited for that element’s role in the WAI-ARIA specification.

Ensures that the aria-roledescription attribute is only applied to elements having explicit or implicit role values.

Inappropriate aria-roledescription attribute values that clash with an element’s implicit or explicit role value can impede the web page’s accessibility. A contradictory aria-roledescription attribute value may have no effect on the application’s accessibility and may trigger behavior that blocks accessibility for entire application sections.

When aria-roledescription attributes are applied to HTML elements not in accordance with WAI-ARIA 1.1, a semantic conflict may occur between the aria-roledescription value and the implicit or explicit element role value, resulting in assistive technology products reporting nonsensical user interface (UI) information that does not accurately represent the intended UI experience.

What this Accessibility Rule Checks

Use aria-roledescription values to adequately explain implicit or explicit element role values.