Overview
ISO/IEC 20071-11:2019 - Guidance on Text Alternatives for Images is an international standard developed by ISO and IEC that provides practical guidance for creating effective text alternatives for static images in electronic documents. This standard supports accessibility by ensuring that essential image information is available to people with visual impairments, as well as others who may rely on text-based content due to technical limitations or personal preference.
The standard applies to all static images in digital formats, including those in presentations (such as slide shows), but does not cover moving images or multimedia content. The guidance is independent of specific implementation mechanisms, making it relevant for a wide range of document types and technology platforms.
Key Topics
- Definition of Text Alternatives: Explains key terms including "primary alternative text" (often the main image description, e.g., alt text), "secondary alternative text" (additional detailed description), and the "main body of text."
- Image Types: Covers various static image types such as drawings, photographs, diagrams, maps, computer-generated images, and composite images, providing tailored advice for each.
- Purpose and Context: Emphasizes the importance of understanding the purpose an image serves within a document, whether informative, decorative, control, or formatting, to determine the appropriate detail and focus of the text alternative.
- Information Structure: Highlights the need to identify image components, analyze content (subjective and objective), and describe relationships, actions, or quantitative data presented in an image.
- Importance Levels: Offers guidance for prioritizing information in text alternatives, distinguishing essential, significant, helpful, and unnecessary details depending on user needs and document context.
- Evaluation and Quality: Recommends processes for composing, organizing, wording, and evaluating text alternatives to achieve clarity, conciseness, and accurate representation.
Applications
ISO/IEC 20071-11:2019 is valuable for a variety of professionals and organizations seeking to enhance accessibility in digital content:
- Web Developers & Designers: Ensuring websites and online documents meet accessibility requirements by providing meaningful alternative text for images.
- Content Creators & Document Authors: Improving the inclusiveness of reports, e-books, presentations, and other digital publications.
- UX/UI Designers: Enhancing user interface accessibility in software, applications, and digital platforms, particularly for users relying on screen readers or other assistive technologies.
- Educational and Government Institutions: Meeting legal and ethical obligations for accessible digital information, supporting equal access for all stakeholders.
- SEO Specialists: Enabling better indexing and retrieval of image content by search engines through well-structured text alternatives.
Following this standard not only fulfills accessibility best practices but also broadens the audience for digital content and improves the overall user experience.
Related Standards
For organizations seeking a comprehensive approach to image and multimedia accessibility, the following related standards provide additional guidance:
- ISO/IEC TS 20071-21: Accessibility guidance for moving images (videos).
- ISO/IEC 20071-23: Further definitions and techniques pertinent to multimedia accessibility.
- ISO/IEC 20071-25: Additional best practices for complex image and content accessibility.
- ISO/IEC Guide 71: Guidelines for considering accessibility in the design process.
Adopting ISO/IEC 20071-11:2019 together with these related standards supports compliance, fosters digital inclusion, and strengthens the reputation of organizations committed to universal accessibility in information technology.