Section 508 Reference
The U.S. Section 508 standards (the 2017 ICT Refresh) incorporate WCAG 2.0 Level A and AA success criteria by reference for web content and electronic documents. Browse the requirements federal agencies are held to.
Showing 16 of 16 requirements
When software is designed to run on a system that has a keyboard, product functions shall be executable from a keyboard
Requirements:
- All functionality must be available from the keyboard
- No exceptions for mouse-only functions unless alternative keyboard access is provided
- Keyboard shortcuts must not conflict with operating system or assistive technology shortcuts
Applications shall not disrupt or disable activated features of other products that are identified as accessibility features
Requirements:
- Focus indicators must be clearly visible
- Focus must not be hidden or obscured by other content
- Focus order must be logical and predictable
Equivalent alternatives for any multimedia presentation shall be synchronized with the presentation
Requirements:
- Videos must have captions for audio content
- Audio descriptions must be provided for visual content
- Synchronized captions must be accurate and complete
Beyond the 4.5:1 minimum required by Section 508, provide a contrast ratio of at least 7:1 for normal text to better support users with low vision.
Requirements:
- Aim for a 7:1 contrast ratio for body text (4.5:1 for large text)
- Verify contrast for text placed over images or gradients
- Offer a high-contrast theme where feasible
Use descriptive headings to organize content into sections, making long documents easier to navigate and skim.
Requirements:
- Break long content into clearly titled sections
- Use a logical heading hierarchy (H1–H6) without skipping levels
- Make heading text describe the section that follows
Where text requires reading ability beyond the lower secondary education level, provide a simpler version or supplemental content.
Requirements:
- Write in plain language and define necessary jargon
- Provide summaries for complex or technical content
- Prefer short sentences and active voice
Make each link’s purpose clear from its link text alone, without relying on the surrounding context.
Requirements:
- Avoid ambiguous link text such as “click here” or “read more”
- Front-load links with their destination or purpose
- Ensure links to different destinations have distinguishable text
Let users adjust how blocks of text are presented to improve readability for low-vision and dyslexic readers.
Requirements:
- Do not fully justify text (avoid uneven word spacing)
- Support line spacing of at least 1.5 within paragraphs
- Ensure text reflows without horizontal scrolling at 200% zoom
All analog television displays 13 inches and larger, and computer equipment that includes analog television receiver or display circuitry, shall be equipped with caption decoder circuitry
Requirements:
- Caption decoder circuitry must be included
- Captions must be displayed when available
- User controls for caption display must be provided
Provide sign language interpretation for prerecorded audio content in synchronized media — valuable for users whose first language is a signed language.
Requirements:
- Offer a sign language track for prerecorded videos with audio
- Position the interpreter clearly and large enough to read
- Keep interpretation synchronized with the spoken content
When pauses in the foreground audio are insufficient to describe the video, pause playback to insert extended audio descriptions.
Requirements:
- Add extended descriptions where standard pauses are too short
- Pause the video as needed to convey essential visual information
- Ensure descriptions cover on-screen text and key actions
Check your documents against Section 508
See exactly where your PDFs fall short of the WCAG 2.0 A & AA criteria Section 508 requires — then fix them.
This reference is based on Section 508 Standards from the U.S. Access Board.