Covered entities are required to provide aids and services unless doing so would result in an “undue burden,” which is defined as significant difficulty or expense. If a particular aid or service would result in an undue burden, the entity must provide another effective aid or service, if possible, that would not result in an undue burden. Determining what constitutes an undue burden will vary from entity to entity and sometimes from one year to the next. The impact of changing economic conditions on the resources available to an entity may also be taken into consideration in making this determination.
That carousel or image slider on your site looks beautiful. That stunning video on autoplay may have cost thousands to produce. Users with cognitive limitations, however, may not comprehend your information quickly enough before the view changes or your video ends. Other users may want to start over, or go back and review something they saw or heard.
Vu said that she gets one question all the time: What are the legal standards? There is no legal standard, but there are guidelines out there: The Web Content Accessibility Guidelines (WCAG), version 2.0, with 3 levels of conformity: A, AA, AAA. They were put out by W3C. Companies can use those guidelines. The Justice Dept. uses the A and AA levels.
Web designers often design in such a way that does not allow the user to adjust font size or color. While they may be protecting their brand, they are also inhibiting some users. Many visually impaired need to use high contrast color settings or very large fonts to read a website. Don't design your website in a way that makes it impossible for them to do this. 
Another federal agency, the Architectural and Transportation Barriers Compliance Board (ATBCB), also known as the Access Board, issues guidelines to ensure that buildings, facilities and transit vehicles are accessible to people with disabilities. The Guidelines & Standards issued under the ADA and other laws establish design requirements for the construction and alteration of facilities. These standards apply to places of public accommodation, commercial facilities, and state and local government facilities.

You can test specific themes for compliance with these guidelines using a tool such as the WAVE Web Accessibility tool.  For sites that require 100% compliance, we recommend testing your theme of choice using the demo page for the theme, for example Twenty Fourteen. We also recommend using Header Text (displaying the Site Title), rather than a Header Image, as some themes will not provide AltText and therefore generate an error in the accessibility tool when a Header Image is set.
Eric Kazda is a leading expert in the interactive development industry with over fifteen years of experience. With a mastery of critical development technologies, Eric has crafted innovative award-winning work for clients both large and small. Coupling this knowledge with a real world understanding of usability and technological feasibility, his work is developed to be accessible by every user.
The Americans with Disabilities Act (ADA) prohibits discrimination against people with disabilities in several areas, including employment, transportation, public accommodations, communications and access to state and local government’ programs and services. As it relates to employment, Title I of the ADA protects the rights of both employees and job seekers. The ADA also establishes requirements for telecommunications relay services. Title IV, which is regulated by the Federal Communications Commission (FCC), also requires closed captioning of federally funded public service announcements.

Reha asked Vu if companies are obligated to comply? Vu said that unlike the physical access world, where any new building has to be compliant no matter what, there’s no such thing in the web world. The Justice Dept. hasn’t said that that’s the default, but they have said that the current regulatory regime requires it anyway. Equal access has been around since 1990.