Web Accessibility

Web accessibility is a broad term that applies to transforming websites and web-based applications so that they are accessible to people with disabilities. The vast majority of  websites are either fully or partially inaccessible to people with disabilities. People who are blind or have vision impairments, for example, rely on screen reader technology to access a website or PDF file. Therefore, these digital environments must undergo a remediation process so that they are compatible with such assistive technology.

Web accessibility is at the core of many international laws that protect people with disabilities from discrimination. These include, but aren’t limited to, Section 508 of the Rehabilitation Act, the Accessibility for Ontarians with Disabilities Act (AODA), and the European Accessibility Act (EAA). Additionally, the DOJ has clarified a number of times that the Americans with Disabilities Act (ADA) applies to web accessibility, and today, many U.S. courts apply its requirements to websites and online spaces.

Web accessibility standards exist to guide website owners and operators in their efforts to create new accessible websites and digital assets, or to remediate existing ones. The most prominent set of web accessibility guidelines is the Web Content Accessibility Guidelines (WCAG). Developed by the World Wide Web Consortium (W3C), WCAG has a significant impact on global web accessibility policy.

The Web Content Accessibility Guidelines (WCAG) include numerous instructions (or success criteria) that, when followed, lead to websites and other web-based content becoming accessible to people with disabilities. WCAG is designed to facilitate accessibility for a wide range of impairments, including, but not limited to, vision impairments, hearing impairments, motor impairments, and cognitive impairments. 

The four principles of WCAG

Despite being long and complex, WCAG is ultimately based on four guiding principles:

1. Perceivable: People should be able to perceive content appearing on your website through their senses of sight, sound, and touch
2. Operable: Website visitors need to be able to operate a website regardless of ability
3. Understandable: A website needs to be easy to understand, and its layout should be simple and predictable
4. Robust: For a website to be considered robust, it needs to make use of clean HTML and CSS code that meets recognized standards. Additionally, it needs to be compatible with assistive tools that people with disabilities use to browse online

WCAG's versions, conformance levels, and success criteria 

Throughout the years, there have been a number of WCAG iterations:

• WCAG 2.0, an earlier version of these standards, was published in 2008
• WCAG 2.1, the current and most up-to-date version of these guidelines, was published in 2018
• WCAG 2.2 was initially released as a draft in February of 2020 and was officially released on October 5th, 2023

All WCAG versions have three levels of conformance:

1. Level A is the minimum level of conformance and covers the most basic accessibility requirements
2. Level AA expands on the requirements of Level A and includes additional guidelines for improved accessibility
3. Level AAA is the highest level of conformance and includes the most stringent accessibility requirements

All versions of WCAG include numerous success criteria at each level of conformance. These include, but certainly aren’t limited to:

• Ensuring compatibility with screen reader technology: Screen readers are relied upon by people with vision impairments to access web-based content. For a website to be compatible with screen readers, it needs to be properly coded to enable smooth navigation and comprehension. For online documents such as PDFs to be compatible with screen readers, they will need to be labeled and tagged properly
• Adding alternative text to meaningful images: People who rely on screen readers cannot access meaningful images (i.e., images that provide pertinent information, and do not appear purely for decorative purposes) if they lack alternative text
• Using proper color contrast ratios between text and its background
• Adding captions to videos
• Ensuring navigation is consistent
• Creating full compatibility with keyboard navigation 

Online documents, such as PDFs and Microsoft Office applications, are often inaccessible to certain people with disabilities. People who are blind or have vision impairments, for example, require PDFs to be properly tagged so that they can be scanned by screen readers. The process of tweaking an existing online document so that it becomes accessible is called document remediation. For the most part, online document remediation projects involve manualintervention (either by individuals or expert service providers), and entail following the WCAG success criterion applicable to online documents.

Web accessibility testing is the process of examining a website or web-based application’s level of conformance with relevant web accessibility standards, such as the Web Content Accessibility Guidelines (WCAG). Web accessibility testing can be conducted manually, by website owners or expert service providers, and by using an automated web accessibility tester. The latter will run an automated audit of a website and examine its level of conformance with WCAG.

As both testing approaches complement each other, many website owners rely on both. Automated tools will provide an initial audit of their website after which website owners can turn to expert service providers to help examine and remediate accessibility issues identified.