OS Digital Accessibility Conformance Methods and Baseline

There are many factors that comprise a conformance review process. Learning about evaluation methods illuminates why the verification process takes time. Performing basic evaluations before submission speeds up the review process.

Evaluation Methods

No two evaluation methods or tools provide the same information. It is imperative to check all standards and assess the usability of content. The following table provides information and characteristics of common evaluation methods.

Evaluation Type	Method Description	Pros and Cons
Automated (Not Sufficient)	A method that utilizes a normative (rule-based) tool that identifies failures within a sub-set of standards. Automated scans alone are not sufficient to provide reliable results. Automated testing provides a high-level indication of conformance. It shows the presence or lack thereof the most basic (i.e., low-hanging fruit) accessibility coding.	High dependency on technology, low dependency on output interpretation. Automated tests cannot apply human subjectivity. Thus, only a small number of the total requirements get tested. Tools that conduct automated scans often leave major gaps in validating conformance.
Manual (Minimally Sufficient)	A method that engages a qualified individual to follow a testing process. The process combines code inspection findings with the outputs of assistive technology (AT). Lends itself to a human deciding whether the intended message is conveyed. While the testing time is longer with this method than automated, it does not have to be a lengthy process.	More thorough content evaluation by accessibility SMEs to ensure conformance with standards. High dependency on human investigation, low or no dependency on tool output. Doesn’t apply AT to support code findings. There is no data on user experience among different browsers and applications.
Hybrid (Preferred)	A method that combines practices used in automated and manual testing. Includes people with disabilities who use AT to understand the user experience and confirm test results. Provides the most comprehensive customer and user experience of the content.	Process enables the most well-rounded results. High dependency on technology, high dependency of human interaction. Using AT and tools alongside manual inspection corroborate the user experience.

Note: Assistive technology (AT) is not an evaluation tool on its own. AT does not suffice in any evaluation method as an interpretation of accessibility. Moreover, many ATs exist for different disabilities. No two products provide an identical user experience.

Conformance Baseline Evaluations

The conformance review acceptance criteria determine testability. Simple checks establish a conformance baseline. The three identified categories of evaluation apply to most content formats. Evaluation time may vary by content size, but the intent is to be quick checks. These evaluations only address a few common issues. Use the appropriate conformance checklist(s) to perform a comprehensive assessment before submission.

Keyboard Access for Interactive Elements

Purpose: Ensure individuals who rely on the keyboard to locate and access content. Examples of interactive elements include Links; radio buttons; checkboxes, drop downs; list boxes; buttons; menus; and other user interface (UI) elements where an action triggers a response.

Conditions: All factors must be true to confirm keyboard accessibility.

Factor 1: Press Tab on the keyboard to navigate to each interactive element. Notice if a dotted rectangle or other visual indicator appears around the element. A dotted rectangle or other visual indicator shows the element has programmatic focus.
1. If focus is not visible on an interactive element, this evaluation fails.
Factor 2: Elements can be tabbed to and away from in a logical or intended order (i.e. top to bottom, left to right).
1. Ensure focus is at the beginning of the desired content area. Use the left mouse button to click near the top of the desired content area. Or press CTRL + Home on the keyboard.
2. Press Tab on the keyboard to navigate through all interactive elements. Check if focused elements are in the intended or logical order.
3. This evaluation fails if:
  1. One or more interactive elements does not receive visual focus at any point in the tabbing cycle.
  2. Or the tabbing cycle of interactive elements is in an illogical or unintended order,
Factor 3: Press Enter or Spacebar on a focused interactive element to trigger an expected action.
1. Test two or three of each type of interactive element. For example, attempt activation or selection of a few checkboxes, buttons, menu items, and links.
2. This evaluation fails if an unintended or no action occurs from activating or selecting an interactive element.

Programmatically Exposed Meaningful Text

Purpose: Ensure all users have access to review and parse essential information. Essential or meaningful text is necessary to understanding the subject matter within context. Images of text or non-exposed text do not allow many user groups to have comparable access to the content.

Exceptions: It is not possible to perform this evaluation on some native software. Bypass this evaluation for logos and branding items.

Condition: The following factor must be true for meaningful text.

Factor 1: All meaningful text is selectable. Unless a descriptive text alternative is available.
1. Hold down the left mouse button and attempt to highlight the suspect text.
2. If highlighting of meaningful text is not possible, this evaluation fails. Meaningful text may appear in a picture of a table, a lengthy infographic, a graphical process flow, or other graphical depictions of text. Note: A text alternative may allow the graphical text to be permissible. Determine if the text alternative includes all meaningful text from the graphic.

Sufficient Contrast of Color Combinations

Purpose: Ensure all content is readable and distinguishable.

Exception: Logos and branding elements are exempt from this rule.

Conditions: The following factor must be true to meet the contrast rule.

Factor 1: Color contrast applies to paragraph text and images of text. The text color against the background color must have a minimum contrast ratio of 4.5:1.
1. Review paragraph text and images of text with questionable contrast. Look for dark shades of a text color against a light shade of a background color (and vice versa). A few helpful color hints include:
  - The combination of black (#000000) on white (#FFFFFF) has a contrast ratio of 21.0:1. Black and white have the greatest possible contrast.
  - HHS Reflexive Blue (#000099) against white has an acceptable contrast ratio of 14.38:1.
  - Text against gradient or patterned backgrounds are likely to encounter contrast issues.
  - Pastel colors against a white background will not pass the contrast rule.
2. Colour Contrast Analyser or manual color checking methods provide the numerical contrast ratio. 4.5:1 is the minimally allowed contrast ratio. The greater the ratio the better for all user groups.