Explanation Behind Decisions
The following sections describe the decision process behind some of the more difficult or controversial topics.
Structure of these guidelines
Summary
- Guidelines: solutions to accessibility problems.
- Outcomes: the desired result (or “outcome”) of reducing accessibility problems. This is what you test for.
- Methods: detailed ways and tests for rating how well your project meets an outcome.
Some of these sections are in this document. You can find others in links within the sections.
Figure 1 shows the core structure of WCAG 3.0. WCAG 3.0 has three levels of content with associated documentation. Guidelines form the top level. Each guideline contains multiple outcomes, with associated critical errors and outcomes scoring. Each outcome contains multiple methods, with an associated description and examples, tests, and test scoring.
Guidelines structure
Guidelines provide a high-level, plain-language version of the content for managers, policy makers, individuals who are new to accessibility, and other individuals who need to understand the concepts but not dive into the technical details. They provide an easy-to-understand way of organizing and presenting the outcomes so that non-experts can learn about and understand the concepts. Each guideline includes a unique, descriptive name along with a high-level plain-language summary. Guidelines address functional needs on specific topics, such as contrast, forms, readability, and more. Guidelines group related outcomes and are technology-independent.
Example: Use sections, headings, and sub-headings to organize your content.
Outcomes structure
Each guideline contains multiple outcomes. Outcomes result from practices that reduce or eliminate barriers that people with disabilities experience. Outcomes form the basis of a flexible and expansive architecture for accessibility guidelines that closely relates to the needs of people with disabilities. Outcomes are designed for use by developers, testers, and other technical experts.
Outcomes are written as testable criteria and include information on how to score the outcome in an optional Conformance Claim. Within a guideline, outcomes have an AND relationship. All relevant outcomes must be addressed but not all outcomes will apply to all technologies and situations. When an outcome does not apply, it is marked NA in the scoring.
Example: Convey hierarchy with semantic structure
Critical errors
Outcomes include the related critical errors that can occur and how to identify them. Not all outcomes have critical errors. Any critical errors will result in the lowest score for the outcome.
Evaluating processes requires counting critical errors that occur within the process and associated views. Critical errors are:
- Errors located anywhere within the view that stop a user from being able to use that view (examples: flashing, keyboard trap, audio with no pause);
- Errors that when located within a process stop a user from completing a process (example: submit button not in tab order); and
- Errors that when aggregated within a view or across a process stop a user from using the view or completing the process (example: a large amount of confusing, ambiguous language).
Outcome rating
Each outcome is rated on a scale of 0 to 4. The rating model is designed to be flexible in order to allow more functional needs of people with disabilities to be included in the guidelines.
Each outcome defines the rating criteria used for that outcome. The rating criteria are designed to be technology agnostic but tie to the available methods so that method level scoring can be rolled up when possible or the tester can make an informed judgment call about the outcome rating.
Methods structure
Each outcome has one or more methods. There are three types of methods:
- All - Methods that apply across all technologies.
- Technology specific - Methods that apply to one of a predetermined list of technologies such as HTML, PDF, or VR.
- Fallback - Methods that apply to emerging or proprietary technology and for technology that does not yet have a method written
When technology specific methods are provided, the outcomes will also include one or more fallback methods.
The methods include detailed information on how to meet the outcome, code samples, working examples, resources, as well as information about testing and scoring the method.
Example: Semantic headings (HTML)
While WCAG 3 Methods have some similarity with WCAG 2 Techniques, they are not the same and are not interchangeable.
Description
Each method includes a detailed technical description of the method with instructions on how the method works that do not depend on examples. If there are dependencies between methods, these are also listed here. Dependencies between methods will be a rare situation.
Examples
Each method also includes working code samples and detailed examples.
Tests
Tests provide ways to check that methods and techniques have been followed. Tests include step-by-step instructions on evaluating the method based on the technology being used. Tests may vary by technology as needed.
Tests specify the unit being tested and the approach to scoring for that test.
Test Scoring
Each method includes information on how to score individual instances of the test. The testing results for methods inform the rating of the related outcome.
Additional Documentation and Scoring Information
Summary
- How-to information: advice written in plain language, including information on how to get started with accessibility.
- Functional needs: how to solve the access problems that people face.
- Functional categories: groups of disability types.
- Conformance levels: scoring your project’s accessibility. There are three levels for your project’s final score: bronze, silver, or gold. Scoring is not required.
Some of these sections are in this document. You can find others in links within the sections.
The core structure has inter-relationships with supporting documents and the scoring process. Functional needs inform both outcomes and functional categories. The tests within methods are used to inform the scores for each outcome. Then outcome scores are aggregated to create scores by functional category and an overall score. These then result in a bronze rating. Silver and gold ratings build on the bronze rating to demonstrate improved accessibility. General information about guidelines is available in How-To documents.
How tos
The How-To content provides explanatory material for each guideline that applies across technologies. This guidance explains how to apply the concepts presented in the guidelines for non-technical readers. This plain language resource includes information on getting started, who the guideline helps and how, as well information for project managers, designers and developers.
The example of a How-To for Structured Content provides basic information organized by tabs to help people get started with accessibility for structured content, plan for implementing accessible structured content across a project, design accessible structured content, and basics for developers new to accessibility of structured content. It also includes information on examples, the outcomes for meeting the guideline, and resources.
Functional needs
The development of WCAG 3 guidelines starts with functional needs. A functional need is a statement that describes a specific gap in one’s ability, or a specific mismatch between ability and the designed environment or context. Functional needs are applied to specific topics (for example: contrast, forms, readability, and more) to identify the barriers experienced by people with disabilities. The barriers in these topics inform the outcomes, which state the conditions to test whether the functional needs have been met. Functional needs are documented in the how-tos, supplementary material accompanying the guidelines.
Example: Use without vision.
The work of cataloging functional needs is still in process and will continue after the First Public Working Draft. Those interested can see more information in the draft Functional Needs.
Functional categories
Functional categories of disabilities group the functional needs of users with disabilities. Functional categories are used when reporting test results in the optional conformance claim.
Functional categories are similar to functional performance criteria in Section 508 [[508-criteria]] and functional performance statements in en 301 549 [[en-301-549]]. The current list of functional categories is:
- Vision and Visual
- Hearing and Auditory
- Sensory Intersections
- Mobility
- Motor
- Physical and Sensory Intersections
- Speech
- Attention
- Language and Literacy
- Learning
- Memory
- Executive
- Mental Health
- Cognitive and Sensory Intersections
The list of functional categories is a draft. Creating meaningful groupings is still a work in progress and currently evolving along with the work on cataloging functional needs. This work will continue after the First Public Working Draft. Those interested can see more information in the document DRAFT Functional Needs.
Conformance Levels
WCAG 3 has an optional scoring system that can better inform organizations on the quality of their accessibility effort. The optional conformance levels provide a way for organizations to report their conformance in simple manner. The bronze level is based on the score in each functional category and the overall score. Silver and gold levels require conforming at the bronze level plus additional improved usability for people with disabilities.
This first draft focuses on bronze level. Future drafts will have more information on silver and gold levels. Bronze level will be similar to WCAG 2 AA, while silver and gold will include more usability-type testing. This is still under development. WCAG 2.X AAA success criteria are generally included in WCAG 3. The design of the scoring model awards more points for implementing the outcomes that come from WCAG 2.X AAA.
How Conformance Fits into the Information Architecture
- Guidelines are general information and intent written in plain language.
- Outcomes are testable statements in plain language.
- Methods are specific examples, instructions, and tests with more technical information.
- Future enhancements include a tagging engine to make it easier for people to find information by tags.
- Many organizations need an API to copy the guideline data to use for their own purposes.
- Guidelines will include:
- updated WCAG 2.1 guidance (technology-specific success criteria will become Methods)
- new guidance written for WCAG 3.0
- new guidance for task completion testing
- Methods are associated with Guidelines. In general, Methods are technology specific.
- Methods include tests for each Method.
- Each Guideline will have multiple Methods with existing WCAG Technique guidance or new Methods written for WCAG 3.0.
- Methods can include tests for determining the percentage points to apply to the conformance score. See the Points and Levels section following for details.
- Methods can provide guidance for:
- User agents
- Authoring tools
- Assistive technology
- Emerging technologies
Selecting a Representative Sample
- Essential functions vary by industry -- gaming will be different than e-commerce. We can't say what has to be tested, the organization needs to determine what is essential.
- The organization (or author) defines the workflows and components, then prioritizes the primary workflows and components to test. See WCAG-EM Steps 2 and 3 to help determine what workflows and components are representative samples.
- The ability to get to the workflow, (like login) also must be accessible.
- There are going to be technical violations of success criteria that don’t impact accessibility (for example, missing alt text that are explained in the text or the same HTML id attribute that aren’t ever referenced) that shouldn’t negatively impact the score. NOTE: There will be further development and amplification of what shouldn’t negatively impact the score. The concept of pass or fail should no longer be binary, but accounts for a concept of sufficient
- People still need to have access to material that still isn’t in the primary flow. Accessibility can be tested even if it doesn’t have a flow. NOTE: There needs to be a way that important sections, like navigation and footer, don’t get overlooked because they aren’t part of the flow.