20 guidance statements support this accessibility characteristic:
- Alternative to auditory alerts - For systems that provide auditory alerts regarding critically important information, people may need to receive visual or tactile alerts instead.
- Alternative to tactile alerts - For systems that provide visual alerts regarding critically important information, people may need to receive auditory or visual alerts instead.
- Alternative to visual alerts - For systems that provide visual alerts regarding critically important information, people may need to receive auditory or tactile alerts instead.
- Appropriate brightness - For systems that present visual content, people may need to change the brightness based on the viewing environment and situation.
- Appropriate speed - For systems that present dynamic images, people may need adjust the presentation speed to enable them to perceive and track them.
- Assistive technology-compatible - For systems with user interfaces, people may need content and operable elements to be accessed and presented through assistive technology.
- Auditory equivalents - For systems with auditory content, people may need that content presented programmatically or need equivalent visual and tactile versions.
- Avoid contrast changes - For systems that present content, people may need to avoid changes to the foreground color that reduce the contrast with the background color.
- Changing content alternatives - For systems that provide changes in content (including state, role or value), people may need visual, auditory, and tactile indications of the change.
- Changing content programmatic - For systems that provide changes in content (including state, role or value), people may need programmatic indcations of the change.
- Hover content - For systems that present hover content, people may need hover content to be dismissible, hoverable, and persistent.
- Multiple simultaneous modalities - For systems that present information, people may need the information presented simultaneously in multiple preferred modalities (visual and audio; tactile and audio; visual and tactile; or visual, audio, and tactile).
- Name, role, value, state - Overlap with programmatic structure and relationships.
- Olfactory equivalents - For systems with olfactory or gustatory content, people may need that content presented programmatically or need equivalent visual, auditory, and tactile versions.
- Output modality choice - As a user with limited or no vision or with limited or no hearing, I need to be able to choose modalities to be used for outputs from the system.
- Separate output control - For systems with assistive technology built into the platform or that work with assistive technology, people may need to be able to control output of assistive technology separate from output of content.
- Unexpected change of context - For systems with interactive components, people may need to be able to input content without unexpected changes in context.
- Unexpected change of focus - For systems with interactive components, people may need to focus on an element without unexpected changes in context.
- Updating content - For systems with automatically updating content, people may need to be able to control it.
- Visual equivalents - For systems with media content, people may need audio descriptions or a text transcript available.