Accessibility Checking for Large Sites
Rocket Validator integrates axe-core version 4.6, into an automated web site scanner.
scope attribute should be used correctly
For screen reader users to efficiently navigate tables, the scope
element must be utilized correctly on tables in accordance with either HTML4 or HTML5 specifications.
If utilized properly, the scope
feature greatly simplifies table navigation for screen reader users. When misused, scope
can make table navigation far more difficult and ineffective.
The assumption made by a screen reader is that a table has a header that identifies a scope. Having an accurate header makes viewing a table for those who use screen readers far more accessible and effective due to the way the devices work.
What this Accessibility Rule Checks
Ensures that tables are correctly using the scope
attribute.
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Related Accessibility Rules Checked by Rocket Validator
An image map consists of a single image with numerous clickable sections. Because screen readers cannot translate graphics into text, an image map, like all images, must contain alternate text for each of the distinct clickable parts, as well as for the larger image itself.
In the absence of alternate text, screen readers often announce the image’s filename. Filenames do not accurately describe images and are therefore inconvenient for screen reader users.
What this Accessibility Rule Checks
Ensures that image map area
elements have alternate text.
Not all ARIA role-attribute combinations are valid. This rule ensures that each role has the required qualities.
Using ARIA attributes in roles where they are not permitted can impair web page accessibility. Using an improper role-attribute combination will have no effect on application accessibility at best and may trigger behavior that blocks accessibility for entire areas of an application at worst.
When ARIA attributes are used on HTML elements that do not conform to WAI-ARIA 1.1, they interfere with the semantics of the elements, causing assistive technology products to display nonsensical user interface (UI) information that does not represent the document’s true UI.
What this Accessibility Rule Checks
Checks that each element with an ARIA role is using only the ARIA attributes that are permitted for that role.
WAI-ARIA role attribute values must be correct. This means that values must be written correctly, correlate to existing ARIA role
values, and not be abstract roles in order to properly display the element’s purpose.
When an assigned WAI-ARIA role value for the parent element is invalid, a developer’s intended accessible technology activity is disabled.
When screen readers and other assistive devices do not understand the job of each element on a web page, they cannot interact with it intelligently or explain the role to the user. When the value for a role is invalid, assistive technologies are unable to communicate the element’s features, properties, and methods. Applying role="table"
to a <ul>
, for example, effectively hijacks the default semantics associated with the <ul>
element in a way that screenreaders do not expect, resulting in unexpected behavior.
What this Accessibility Rule Checks
Check all elements with WAI-ARIA role attribute values to confirm the role value is correct. The role value must be appropriate for the element in the context of the document.
ARIA widget roles must contain attributes describing the widget’s state or properties.
ARIA widget roles necessitate additional properties describing the widget’s state. If a needed attribute is missing, the widget’s status is not conveyed to users of screen readers.
Some roles function as composite user interface widgets. As such, they serve as containers that manage the widgets they contain. When an object inherits from several ancestors and one ancestor indicates support for a property and another says the property is required, the property becomes required on the inheriting object. In some circumstances, default values are sufficient to meet ARIA attribute requirements.
When required state and property attributes for specific roles (and subclass roles) are missing, screen readers may be unable to communicate the element’s role definition to the user.
What this Accessibility Rule Checks
Checks all elements with the role attribute to ensure that all necessary attributes are defined.
12,500 Accessibility and HTML checks per week. Fully automated.
Let our automated scanner check your large sites using Axe Core and W3C Validator.
Some ARIA parent role
values must contain specific child elements and role
values in order to execute the intended accessibility function.
WAI-ARIA outlines specifically, for each role, which child and parent roles are permitted and/or required. ARIA role
s lacking needed child role
s will not be able to execute the desired accessibility functions.
The user’s context must be communicated by assistive technology. In a treeitem
, for instance, it is essential to know the parent (container), item, and siblings in the folder. This is possible in two ways:
- Code order or DOM: The context required is frequently evident from the code order or DOM.
-
ARIA: ARIA (such as
aria-owns
) can be used to provide relationships when the hierarchy differs from the code structure or the DOM tree.
What this Accessibility Rule Checks
Checks each element containing a WAI-ARIA role for the presence of all requisite child roles.
Certain ARIA roles must be enclosed by specific parent roles
in order to carry out their intended accessibility functions.
WAI-ARIA outlines specifically, for each role, which child and parent roles are permitted and/or required. Elements with ARIA role
values that lack needed parent element role
values will prevent assistive technology from functioning as the developer intended.
When it is necessary to convey context to a user of assistive technology in the form of hierarchy (for example, the importance of a parent container, item, or sibling in a folder tree), and the hierarchy is not the same as the code structure or DOM tree, it is impossible to provide relationship information without using ARIA role parent elements.
What this Accessibility Rule Checks
Checks each WAI-ARIA role-containing element to confirm that all required parent roles are present.
50,000 Accessibility and HTML checks per month. Fully automated.
Let our automated scanner check your large sites using Axe Core and W3C Validator.
Valid values must be present for ARIA properties that begin with aria-
.
To fulfill the intended accessibility purpose, these values must be written correctly and relate to values that make sense for a certain property.
ARIA attributes (those beginning with aria-
) must have legitimate values. For a given attribute to fulfill the intended accessibility function, these values must be written correctly and correlate to values that make sense.
A diverse range of values are accepted for many ARIA attributes. There must be permitted values, acceptable “undefined” values, and acceptable “default” values.
Content that does not adhere to the permitted values is inaccessible to users of assistive technology.
What this Accessibility Rule Checks
Verifies that the WAI-ARIA attributes’ values are correct for each element that contains them.
The names of ARIA attributes beginning with “aria-“ must be correct.
A reference to an invalid attribute or an attribute that doesn’t exist will result in a violation of this rule.
The accessibility function intended by the developer will not be fulfilled if the developer uses an invalid or misspelled ARIA attribute.
User interface components meant to increase the accessibility and interoperability of web and application content must adhere to properly worded and up-to-date ARIA properties in order for assistive technology to provide suitable information to people with disabilities.
Insufficient usage of the WAI-ARIA 1.1 W3C Recommendation’s attributes prevents developers from correctly communicating user interface actions and structural information to assistive technology in document-level markup.
What this Accessibility Rule Checks
Verifies that all elements that contain WAI-ARIA attributes have those attributes and that they are legitimate attributes.
It is a best practice to make sure each heading element, denoted by the tags <h1>
through <h6>
, contains text.
Users of screen readers are informed when a heading tag is present. Users may become confused or even unable to access information on the page’s structure if the headline is blank or the text cannot be accessible.
Users of this technology won’t be able to hear the content of a header if the text inside it is inaccessible to a screen reader. Users using screen readers must be able to access the contents since headings reveal the structure of a webpage.
Applying header markup (<h1>
through <h6>
) is a quick approach to make content stand out, but doing so will make it more difficult for those using assistive technology to navigate a website.
Due to the fact that search engines use headings when filtering, arranging, and showing results, headers offer advantages beyond just making a page more accessible. Making your website more searchable is another benefit of making it more accessible.
Users of screen readers can navigate between headings in the same manner that sighted users might skim a page to gain a sense of its contents. Users, especially those who use screen readers, can save a ton of time and stress by using well-written, logically-arranged headings.
What this Accessibility Rule Checks
Ensures that headings have content and that a screen reader can access that content.
Whether native HTML or a custom widget, user input elements need to play the right roles in order to make their meaning clear to screen reader users when they are focused on and landed on. If a custom widget, the element’s function must be correctly exposed by using appropriate ARIA role
values rather than abstract roles.
In order for screen reader technology to convey information to users, elements in the focus order must play a function appropriate for interactive content.
If interactive content elements do not have the proper roles, the developer’s planned accessibility function cannot be carried out by the role.
When screen readers and other assistive technologies cannot communicate to the user the proper role of each element on the web page, they are unable to interact with it sensibly. Assistive technology cannot communicate with an HTML element’s set of features, properties, and ways of communicating information to and/or from the user when the value for a role is invalid.
What this Accessibility Rule Checks
Verifies that the role attribute value is accurate and suitable for all interactive components in the focus order, regardless of whether they are native HTML or customized ARIA widgets.
50,000 Accessibility and HTML checks per month. Fully automated.
Let our automated scanner check your large sites using Axe Core and W3C Validator.