From CDOT Wiki
<span>One of the requirements of the BigBlueButton project is for it accessible to all users without limitation, which encompasses both direct access (native to the application) and indirect access (compatible with assistive technologies
such as screen readers) methods. Accessibility has already been fully implemented in the Flash client and is in development in the HTML5 client. The main accessibility features that were implemented include screen reader support, keyboard navigation, and localization. Since a large portion of the users of this application are students, the content and interface of the application is required to be equally functional for individuals with physical impairments and disabilities. All accessibility features have been implemented in compliance with the [https://www.w3.org/TR/wai-aria-1.1/ ARIA (Accessible Rich Internet Applciations) standards] and [https://www.w3.org/TR/WCAG20/ WCAG (Web Content Accessibility Guidelines)].
In regards to screen reader implementation, all text within the application and anything that the user can interact with (including buttons
and menu's) has a description which is interpreted by the screen reader and read out to the user to give meaning to the things they cannot see. Keyboard navigation and keyboard shortcuts have also been implemented to assist users with vision impairment so that they can still navigate through the entire application without having to see it on a screen.
For international students or users of the application whose first language is not english, localization has been implemented to support the user's native language, with a wide variety of languages to choose from. These language localizations are constantly being improved and updated by the community as the application develops further.</span>