Computer accessibility - Assessment and Standards

Assessment and Standards in Accessibility Introduction Digital accessibility is not just a best practice—it's a legal requirement in many jurisdictions. Organizations must ensure their electronic content and technology are usable by everyone, including people with disabilities. This section covers two major frameworks that establish accessibility standards: the U.S. legal requirement known as Section 508, and the international technical standard ISO 9241-171. United States Section 508 Requirements Background and Legal Framework Section 508 of the Rehabilitation Act of 1973 is a civil rights law that mandates accessibility in the United States. Specifically, it requires all U.S. federal agencies to make their electronic and information technology accessible to employees and members of the public with disabilities. This applies to agency websites, documents, software, and any other digital content that federal organizations produce or manage. The 2018 Access Board Rule The Access Board—the independent agency that sets accessibility standards for federal technology—issued its final rule in January 2018. This rule updated Section 508 compliance requirements by mandating that all federal electronic content must meet Level A and Level AA success criteria from the Web Content Accessibility Guidelines 2.0 (WCAG 2.0). What does this mean in practice? WCAG 2.0 is an internationally recognized standard that provides testable criteria for accessibility. Level A represents the minimum level of accessibility, while Level AA represents a higher level of accessibility. By requiring federal agencies to meet both Level A and Level AA, the regulation ensures that federal digital content is substantially accessible to people with a wide range of disabilities, including visual, hearing, mobility, and cognitive disabilities. Important Exceptions for Non-Web Documents Interestingly, the rule provides four specific exceptions for non-web documents (such as PDFs or downloadable files). These exceptions mean that some WCAG 2.0 criteria don't apply to non-web content: Bypass Blocks: Users don't need the ability to bypass repeated content blocks Multiple Ways: There's no requirement to provide multiple ways to find content Consistent Navigation: Navigation doesn't need to be consistent across pages Consistent Identification: Components with the same functionality don't need identical identification These exceptions exist because non-web documents have different structural constraints than websites. However, all other WCAG 2.0 Level A and AA criteria still apply. International Standard ISO 9241-171:2008 Purpose and Scope While Section 508 applies specifically to U.S. federal agencies, organizations worldwide follow ISO 9241-171:2008, an international standard for software accessibility. ISO 9241-171 provides ergonomic guidance and specifications for designing accessible software for public use. Rather than being a legal requirement, it's a best-practice standard that helps organizations design and evaluate their software systematically. Priority Levels: Required vs. Recommended ISO 9241-171 structures its requirements into two priority levels: Required: These are essential accessibility features that software should include. Meeting these requirements ensures basic accessibility for users with disabilities. Recommended: These are additional features that further enhance accessibility and usability. While not strictly necessary, they significantly improve the user experience. This tiered approach allows organizations to prioritize their accessibility efforts. Many start by implementing all "Required" criteria, then work toward incorporating "Recommended" ones as resources permit. Testing and Evaluation A key feature of ISO 9241-171 is that it includes a checklist for recording software testing results. This checklist helps organizations systematically evaluate whether their software meets the standard's criteria. By using the checklist, developers and quality assurance teams can identify gaps in accessibility and track improvements over time. <extrainfo> Practical Example of Accessibility Implementation The image below shows an example of accessibility links on a real website (BBC News): Notice the "Accessibility Links" section that appears prominently on the page. These links—"Skip to content," "Skip to navigation," "Skip to search," and "Access keys help"—are practical implementations of WCAG guidelines. They allow users who navigate via keyboard (rather than a mouse) to quickly jump to the most important parts of the page, and they provide access to keyboard shortcuts. This is exactly the type of feature that both Section 508 compliance and ISO 9241-171 standards encourage. </extrainfo> Key Takeaways Both Section 508 and ISO 9241-171 establish that accessibility is not optional—it's a professional and often legal obligation. Section 508 provides legal requirements for U.S. federal agencies with specific success criteria, while ISO 9241-171 offers international guidance for software accessibility with a practical checklist approach. Understanding these standards helps digital professionals create technology that is genuinely usable by everyone.