Minimum Digital Accessibility Standards

The Minimum Digital Accessibility Standards (MDAS) provide implementation standards for Ohio State’s Digital Accessibility policy. Maintained by the Digital Accessibility Center under the direction of the ADA Coordinator’s Office, originally adopted in 2004 as the Minimum Web Accessibility Standards, updated, expanded, and renamed to Minimum Digital Accessibility Standards (MDAS) in 2017, the goal of MDAS is to ensure that Digital Information and Services are functionally accessible to persons with Disabilities.

According to Ohio State’s Digital Accessibility policy, all digital Information and Services to be used by Ohio State University faculty/staff, program participants, the general public or other university constituencies are required to be compliant with the non-discrimination provisions of the Americans with Disabilities Act (ADA), as amended, and Section 504 of the Rehabilitation Act. This document provides elaboration and standards to help OSU developers and purchasing agents meet the Digital Accessibility Policy.

To be compliant with our Digital Accessibility policy a person with a disability must be afforded the opportunity to acquire the same information, engage in the same interactions, and enjoy the same services as a person without a disability in an equally effective and equally integrated manner, with substantially equivalent ease of use. A person with a disability must be able to obtain the information or service as fully, equally, and independently as a person without a disability.

To help satisfy the requirement to comply with the ADA and meet Digital Accessibility policy and the Minimum Digital Accessibility Standards, a digital information or service should be designed to be functionally accessible, rather than merely technically accessible. While technical accessibility determines whether a resource is coded to an accepted accessibility standard, to be functionally accessible means that any person can use the resource effectively to perform an available task. Coding to an accepted standard is often a means of approaching functional accessibility, but achieving functional accessibility means that resources are easy to use and content is clear and unambiguous for all users, regardless of ability.

To be functionally accessible, a Digital Information or Service must consider use by people who may:

  • have severe or moderate visual impairment
  • be colorblind
  • be deaf or hard of hearing
  • have motor disabilities
  • have cognitive disabilities

Users with severe visual impairments typically use screen readers, programs that navigate the web browser’s rendering of the code of a web page and read aloud the content. Screen readers identify not only text, but also alternate text added to provide a description for images. They facilitate full interaction with web page content and objects. And they allow users to skip between chunks of content by link, heading, form element, and content block, among other means. Invalid or lax coding practices, minimal logical structure and semantics, and inappropriate or missing textual descriptions for images or links make navigation and understanding of web content difficult or impossible for screen reader reliant users. Some usages of JavaScript and plug-ins can be inaccessible to screen readers, as well.

The screen reader used most on campus is Freedom Scientific’s JAWS for Windows, though there is also significant use of VoiceOver, the screen reader on Mac and iOS devices. Because of the variety of screen readers in use on campus, testing on more than one platform, including a mobile platform is strongly recommended. NVDA is a free screen reader for Windows which tends to be in the vanguard in its handling of modern web page/application implementations. The university recommends it for testing, along with VoiceOver on Mac and iOS.

Users with moderate to severe visual impairments (“low vision”) typically enlarge the screen fonts, either by using the browser’s zoom or text scaling facilities or by using screen magnification software. These users may also set their operating system to a “high-contrast” mode or use custom style sheets to increase the contrast between foreground and background.

Users with color blindness have problems distinguishing between certain colors. Digital Information or Services should avoid instances where functionality or meaning is conveyed solely by color differences.

Users who are deaf or hard of hearing may rely on transcripts of audio content, captioned video, and alternatives to auditory cuing.

According to best practices and our Minimum Digital Accessibility Standards, all video content must have a synchronized text track (caption), providing transcription of spoken text, speaker identification, and text equivalents of non-verbal audio (a.k.a., sound effects), as appropriate. Audio podcasts and other spoken audio must be accompanied by a full text transcription. Web pages or applications that use audio cues also should provide a visual, preferably text-based, cue.

Users with various motor disabilities may have difficulty using the mouse as a pointing device, due to nerve conditions, disease, or injury. Limited motor acuity may affect response times and accuracy in selecting navigation or options within forms and other controls. Repetitive stress and other less severe motor disabilities may make over-reliance on the keyboard difficult – for example, excessive tabbing to move through controls. Users with limited upper-body mobility may use speech recognition for input or other input devices which mimic keyboard input, or they may rely solely on the keyboard for all input.

Developers should test to make sure all navigation, form, and other control elements in web pages and application interfaces are accessible and operable via the keyboard alone, and look to see that if timed responses are necessary there is the ability to extend the time, and that that functionality is easy to understand and locate in the page or application. Also try to judge the impact on usability afforded by the quantity and complexity of input required for navigation, form, or other input. The university also recommends testing the usability of web forms and applications with speech recognition software, such as Dragon Naturally Speaking or Windows Speech Recognition.

Cognitive disability is the most broad and varied category of disability. Most users with disabilities registered through our Office of Student Life Disability Services have some form of cognitive disability. Thus, attention to usability problems that may be encountered by users with cognitive disabilities will have proportionally the greatest positive impact on consumers of Digital Information or Services. Cognitive disabilities include conditions affecting reading and verbal comprehension, learning disabilities, attention and distractibility disorders, conditions affecting memory and processing of large amounts of information, and problems comprehending information presented mathematically or graphically.

In general, try to assess the general usability and comprehensibility – clarity in presentation and logical and spatial organization – of digital resources. Ensuring correct grammar and spelling and reducing verbal complexity will have a positive impact for users with certain cognitive disabilities, as well.

The MDAS are based on the World Wide Web Consortium’s Web Content Accessibility Guidelines (WCAG) 2.0. Ohio State is adopting the Web Content Accessibility Guidelines 2.0 at conformance level AA as standards. The standards also adopt Accessible Rich Internet Applications (WAI-ARIA 1.1 and Guidance on Applying WCAG 2.0 to Non-Web Information and Communications Technologies (WCAG2ICT).

The Web Content Accessibility Guidelines are divided into layers of guidance to serve the needs of various audiences including overall principles, general guidelines, and testable success criteria.

Note: The following language is an excerpt from the Web Content Accessibility Guidelines. Ohio State is adopting success criteria from conformance levels A and AA for implementation.

Principle 1: Perceivable – Information and user interface components must be presentable to users in ways they can perceive.

Guideline 1.1 Text Alternatives: Provide text alternatives for any non-text content so that it can be changed into other forms people need, such as large print, braille, speech, symbols or simpler language.

Understanding Guideline 1.1

1.1.1 Non-text Content: All non-text content that is presented to the user has a text alternative that serves the equivalent purpose, except for the situations listed below. (Level A)

  • Controls, Input: If non-text content is a control or accepts user input, then it has a name that describes its purpose. (Refer to Guideline 4.1 for additional requirements for controls and content that accepts user input.)
  • Time-Based Media: If non-text content is time-based media, then text alternatives at least provide descriptive identification of the non-text content. (Refer to Guideline 1.2 for additional requirements for media.)
  • Test: If non-text content is a test or exercise that would be invalid if presented in text, then text alternatives at least provide descriptive identification of the non-text content.
  • Sensory: If non-text content is primarily intended to create a specific sensory experience, then text alternatives at least provide descriptive identification of the non-text content.
  • CAPTCHA: If the purpose of non-text content is to confirm that content is being accessed by a person rather than a computer, then text alternatives that identify and describe the purpose of the non-text content are provided, and alternative forms of CAPTCHA using output modes for different types of sensory perception are provided to accommodate different disabilities.
  • Decoration, Formatting, Invisible: If non-text content is pure decoration, is used only for visual formatting, or is not presented to users, then it is implemented in a way that it can be ignored by assistive technology.

How to Meet 1.1.1 | Understanding 1.1.1

Guideline 1.2 Time-based Media: Provide alternatives for time-based media.

Understanding Guideline 1.2

1.2.1 Audio-only and Video-only (Prerecorded): For prerecorded audio-only and prerecorded video-only media, the following are true, except when the audio or video is a media alternative for text and is clearly labeled as such: (Level A)

  • Prerecorded Audio-only: An alternative for time-based media is provided that presents equivalent information for prerecorded audio-only content.
  • Prerecorded Video-only: Either an alternative for time-based media or an audio track is provided that presents equivalent information for prerecorded video-only content.

How to Meet 1.2.1 | Understanding 1.2.1

1.2.2 Captions (Prerecorded): Captions are provided for all prerecorded audio content in synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)

How to Meet 1.2.2 | Understanding 1.2.2

1.2.3 Audio Description or Media Alternative (Prerecorded): An alternative for time-based media or audio description of the prerecorded video content is provided for synchronized media, except when the media is a media alternative for text and is clearly labeled as such. (Level A)

How to Meet 1.2.3 | Understanding 1.2.3

1.2.4 Captions (Live): Captions are provided for all live audio content in synchronized media. (Level AA)

How to Meet 1.2.4 | Understanding 1.2.4

1.2.5 Audio Description (Prerecorded): Audio description is provided for all prerecorded video content in synchronized media. (Level AA)

How to Meet 1.2.5 | Understanding 1.2.5

Guideline 1.3 Adaptable: Create content that can be presented in different ways (for example simpler layout) without losing information or structure.

Understanding Guideline 1.3

1.3.1 Info and Relationships: Information, structure, and relationships conveyed through presentation can be programmatically determined or are available in text. (Level A)

How to Meet 1.3.1 | Understanding 1.3.1

1.3.2 Meaningful Sequence: When the sequence in which content is presented affects its meaning, a correct reading sequence can be programmatically determined. (Level A)

How to Meet 1.3.2 | Understanding 1.3.2

1.3.3 Sensory Characteristics: Instructions provided for understanding and operating content do not rely solely on sensory characteristics of components such as shape, size, visual location, orientation, or sound. (Level A)

Note: For requirements related to color, refer to Guideline 1.4.

How to Meet 1.3.3 | Understanding 1.3.3

Guideline 1.4 Distinguishable: Make it easier for users to see and hear content including separating foreground from background.

Understanding Guideline 1.4

1.4.1 Use of Color: Color is not used as the only visual means of conveying information, indicating an action, prompting a response, or distinguishing a visual element. (Level A)

Note: This success criterion addresses color perception specifically. Other forms of perception are covered in Guideline 1.3 including programmatic access to color and other visual presentation coding.

How to Meet 1.4.1 | Understanding 1.4.1

1.4.2 Audio Control: If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level. (Level A)

Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

How to Meet 1.4.2 | Understanding 1.4.2

1.4.3 Contrast (Minimum): The visual presentation of text and images of text has a contrast ratio of at least 4.5:1, except for the following: (Level AA)

  • Large Text: Large-scale text and images of large-scale text have a contrast ratio of at least 3:1;
  • Incidental: Text or images of text that are part of an inactive user interface component, that are pure decoration, that are not visible to anyone, or that are part of a picture that contains significant other visual content, have no contrast requirement.
  • Logotypes: Text that is part of a logo or brand name has no minimum contrast requirement.

How to Meet 1.4.3 | Understanding 1.4.3

1.4.4 Resize text: Except for captions and images of text, text can be resized without assistive technology up to 200 percent without loss of content or functionality. (Level AA)

How to Meet 1.4.4 | Understanding 1.4.4

1.4.5 Images of Text: If the technologies being used can achieve the visual presentation, text is used to convey information rather than images of text except for the following: (Level AA)

  • Customizable: The image of text can be visually customized to the user's requirements;
  • Essential: A particular presentation of text is essential to the information being conveyed.

Note: Logotypes (text that is part of a logo or brand name) are considered essential.

How to Meet 1.4.5 | Understanding 1.4.5

Principle 2: Operable – User interface components and navigation must be operable.

Guideline 2.1 Keyboard Accessible: Make all functionality available from a keyboard.

Understanding Guideline 2.1

2.1.1 Keyboard: All functionality of the content is operable through a keyboard interface without requiring specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints. (Level A)

Note 1: This exception relates to the underlying function, not the input technique. For example, if using handwriting to enter text, the input technique (handwriting) requires path-dependent input but the underlying function (text input) does not.

Note 2: This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation.

How to Meet 2.1.1 | Understanding 2.1.1

2.1.2 No Keyboard Trap: If keyboard focus can be moved to a component of the page using a keyboard interface, then focus can be moved away from that component using only a keyboard interface, and, if it requires more than unmodified arrow or tab keys or other standard exit methods, the user is advised of the method for moving focus away. (Level A)

Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

How to Meet 2.1.2 | Understanding 2.1.2

Guideline 2.2 Enough Time: Provide users enough time to read and use content.

Understanding Guideline 2.2

2.2.1 Timing Adjustable: For each time limit that is set by the content, at least one of the following is true: (Level A)

  • Turn off: The user is allowed to turn off the time limit before encountering it; or
  • Adjust: The user is allowed to adjust the time limit before encountering it over a wide range that is at least ten times the length of the default setting; or
  • Extend: The user is warned before time expires and given at least 20 seconds to extend the time limit with a simple action (for example, "press the space bar"), and the user is allowed to extend the time limit at least ten times; or
  • Real-time Exception: The time limit is a required part of a real-time event (for example, an auction), and no alternative to the time limit is possible; or
  • Essential Exception: The time limit is essential and extending it would invalidate the activity; or
  • 20 Hour Exception: The time limit is longer than 20 hours.

Note: This success criterion helps ensure that users can complete tasks without unexpected changes in content or context that are a result of a time limit. This success criterion should be considered in conjunction with Success Criterion 3.2.1, which puts limits on changes of content or context as a result of user action.

How to Meet 2.2.1 | Understanding 2.2.1

2.2.2 Pause, Stop, Hide: For moving, blinking, scrolling, or auto-updating information, all of the following are true: (Level A)

  • Moving, blinking, scrolling: For any moving, blinking or scrolling information that (1) starts automatically, (2) lasts more than five seconds, and (3) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it unless the movement, blinking, or scrolling is part of an activity where it is essential; and
  • Auto-updating: For any auto-updating information that (1) starts automatically and (2) is presented in parallel with other content, there is a mechanism for the user to pause, stop, or hide it or to control the frequency of the update unless the auto-updating is part of an activity where it is essential.

Note 1: For requirements related to flickering or flashing content, refer to Guideline 2.3.

Note 2: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

Note 3: Content that is updated periodically by software or that is streamed to the user agent is not required to preserve or present information that is generated or received between the initiation of the pause and resuming presentation, as this may not be technically possible, and in many situations could be misleading to do so.

Note 4: An animation that occurs as part of a preload phase or similar situation can be considered essential if interaction cannot occur during that phase for all users and if not indicating progress could confuse users or cause them to think that content was frozen or broken.

How to Meet 2.2.2 | Understanding 2.2.2

Guideline 2.3 Seizures: Do not design content in a way that is known to cause seizures.

Understanding Guideline 2.3

2.3.1 Three Flashes or Below Threshold: Web pages do not contain anything that flashes more than three times in any one second period, or the flash is below the general flash and red flash thresholds. (Level A)

Note: Since any content that does not meet this success criterion can interfere with a user's ability to use the whole page, all content on the Web page (whether it is used to meet other success criteria or not) must meet this success criterion. See Conformance Requirement 5: Non-Interference.

How to Meet 2.3.1 | Understanding 2.3.1

Guideline 2.4 Navigable: Provide ways to help users navigate, find content, and determine where they are.

Understanding Guideline 2.4

2.4.1 Bypass Blocks: A mechanism is available to bypass blocks of content that are repeated on multiple Web pages. (Level A)

How to Meet 2.4.1 | Understanding 2.4.1

2.4.2 Page Titled: Web pages have titles that describe topic or purpose. (Level A)

How to Meet 2.4.2 | Understanding 2.4.2

2.4.3 Focus Order: If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability. (Level A)

How to Meet 2.4.3 | Understanding 2.4.3

2.4.4 Link Purpose (In Context): The purpose of each link can be determined from the link text alone or from the link text together with its programmatically determined link context, except where the purpose of the link would be ambiguous to users in general. (Level A)

How to Meet 2.4.4 | Understanding 2.4.4

2.4.5 Multiple Ways: More than one way is available to locate a Web page within a set of Web pages except where the Web Page is the result of, or a step in, a process. (Level AA)

How to Meet 2.4.5 | Understanding 2.4.5

2.4.6 Headings and Labels: Headings and labels describe topic or purpose. (Level AA)

How to Meet 2.4.6 | Understanding 2.4.6

2.4.7 Focus Visible: Any keyboard operable user interface has a mode of operation where the keyboard focus indicator is visible. (Level AA)

How to Meet 2.4.7 | Understanding 2.4.7

Principle 3: Understandable – Information and the operation of user interface must be understandable.

Guideline 3.1 Readable: Make text content readable and understandable.

Understanding Guideline 3.1

3.1.1 Language of Page: The default human language of each Web page can be programmatically determined. (Level A)

How to Meet 3.1.1 | Understanding 3.1.1

3.1.2 Language of Parts: The human language of each passage or phrase in the content can be programmatically determined except for proper names, technical terms, words of indeterminate language, and words or phrases that have become part of the vernacular of the immediately surrounding text. (Level AA)

How to Meet 3.1.2 | Understanding 3.1.2

Guideline 3.2 Predictable: Make Web pages appear and operate in predictable ways.

Understanding Guideline 3.2

3.2.1 On Focus: When any component receives focus, it does not initiate a change of context. (Level A)

How to Meet 3.2.1 | Understanding 3.2.1

3.2.2 On Input: Changing the setting of any user interface component does not automatically cause a change of context unless the user has been advised of the behavior before using the component. (Level A)

How to Meet 3.2.2 | Understanding 3.2.2

3.2.3 Consistent Navigation: Navigational mechanisms that are repeated on multiple Web pages within a set of Web pages occur in the same relative order each time they are repeated, unless a change is initiated by the user. (Level AA)

How to Meet 3.2.3 | Understanding 3.2.3

3.2.4 Consistent Identification: Components that have the same functionality within a set of Web pages are identified consistently. (Level AA)

How to Meet 3.2.4 | Understanding 3.2.4

Guideline 3.3 Input Assistance: Help users avoid and correct mistakes.

Understanding Guideline 3.3

3.3.1 Error Identification: If an input error is automatically detected, the item that is in error is identified and the error is described to the user in text. (Level A)

How to Meet 3.3.1 | Understanding 3.3.1

3.3.2 Labels or Instructions: Labels or instructions are provided when content requires user input. (Level A)

How to Meet 3.3.2 | Understanding 3.3.2

3.3.3 Error Suggestion: If an input error is automatically detected and suggestions for correction are known, then the suggestions are provided to the user, unless it would jeopardize the security or purpose of the content. (Level AA)

How to Meet 3.3.3 | Understanding 3.3.3

3.3.4 Error Prevention (Legal, Financial, Data): For Web pages that cause legal commitments or financial transactions for the user to occur, that modify or delete user-controllable data in data storage systems, or that submit user test responses, at least one of the following is true: (Level AA)

  1. Reversible: Submissions are reversible.
  2. Checked: Data entered by the user is checked for input errors and the user is provided an opportunity to correct them.
  3. Confirmed: A mechanism is available for reviewing, confirming, and correcting information before finalizing the submission.

How to Meet 3.3.4 | Understanding 3.3.4

Principle 4: Robust – Content must be robust enough that it can be interpreted reliably by a wide variety of user agents, including assistive technologies.

Guideline 4.1 Compatible: Maximize compatibility with current and future user agents, including assistive technologies.

Understanding Guideline 4.1

4.1.1 Parsing: In content implemented using markup languages, elements have complete start and end tags, elements are nested according to their specifications, elements do not contain duplicate attributes, and any IDs are unique, except where the specifications allow these features. (Level A)

Note: Start and end tags that are missing a critical character in their formation, such as a closing angle bracket or a mismatched attribute value quotation mark are not complete.

How to Meet 4.1.1 | Understanding 4.1.1

4.1.2 Name, Role, Value: For all user interface components (including but not limited to: form elements, links and components generated by scripts), the name and role can be programmatically determined; states, properties, and values that can be set by the user can be programmatically set; and notification of changes to these items is available to user agents, including assistive technologies. (Level A)

Note: This success criterion is primarily for Web authors who develop or script their own user interface components. For example, standard HTML controls already meet this success criterion when used according to specification.

How to Meet 4.1.2 | Understanding 4.1.2