Data visualization – the use of charts, pictures, and other visual interpretations of information – is a vital tool used online to communicate complex data relationships. For people with visual impairments, however, these tools are severely diminished or fully inaccessible. Users of assistive screen-readers typically only have access to a few sentences that describe the chart or graphic, and a link to the underlying data table – a poor substitute for the insights conveyed by data visualizations.
A team of researchers at the Massachusetts Institute of Technology (MIT) is seeking to change this, creating screen-reader friendly data visualizations that offer a more comparable experience to that of sighted individuals. The team developed several visualization prototypes that provide text descriptions at varying levels of detail, so users can drill down from high-level data to more detailed information with a few clicks. One prototype allows readers to use up and down arrows to navigate between different levels of information, and right and left keys to cycle through information on that level. Another prototype uses the same arrow keys, but also includes a drop-down menu that allows readers to jump quickly to other key chart locations. Users expressed that the prototypes enabled them to identify patterns in data more rapidly – similar to the insights gained by a sighted person viewing a data visualization.
While guidelines for accessible data visualization are in the early stages of their formulation, standards are an important element in other tools that provide support for people with impaired vision. ANSI/IES RP-28-20, Recommended Practice: Lighting and the Visual Environment for Older Adults and the Visually Impaired, seeks to mitigate the loss of independence faced by older adults and people who are partially sighted, maximizing vision with appropriate lighting and a supportive visual environment. This American National Standard (ANS) was developed by the Illuminating Engineering Society (IES), a member and accredited standards developer of the American National Standards Institute (ANSI).
ANSI Z80.9-2020, Opthalmics – Devices for Low Vision, guides optical and mechanical requirements and test methods for optical and electro-optical devices for use by visually impaired persons, such as magnifying reading glasses, loupes, small telescopes, and video magnifier systems. This ANS was developed by Accredited Standards Committee (ASC) Z80 (The Vision Council).
INCITS/ISO/IEC 7811-9:2015, Identification Cards – Recording Technique – Part 9: Tactile Identifier Mark, guides embossed dots used on identification cards so that people with visual impairments can distinguish cards through tactile recognition. This standard was developed by ISO/IEC Joint Technical Committee 1, Information Technology, subcommittee 17, Cards and security devices for personal identification, and adopted as an ANS. ANSI holds the secretariat to JTC 1, and ANSI member and accredited standards developer InterNational Committee for Information Technology Standards (INCITS) is the Technical Advisory Group (TAG) administrator to this TC and SC.
CEA 2041, Standard for a Round Tactile Indicator, defines the size, shape, and placement of a tactile indicator – a “nib” – on the numeric keys of handheld remote controls for consumer electronics products. This standard way of identifying numbers through the “nib” assists users who are blind or visually impaired in determining the location of the numbers they seek. The Consumer Technology Association (CTA), an ANSI member and accredited standards developer, developed this standard.
The multidisciplinary team at MIT is continuing their research, testing the prototypes and refining them based on feedback from the communities that will use them. The goal is to one day build a software package that operates seamlessly within existing design tools and gives visualizations an accessible, navigable structure. Learn more: Making data visualizations more accessible for blind and low-vision individuals.