The Federal Communications Commission (FCC) enforces regulations covering telecommunication services. Title IV of the ADA covers telephone and television access for people with hearing and speech disabilities. It requires telephone and Internet companies to provide a nationwide system of telecommunications relay services that allow people with hearing and speech disabilities to communicate over the telephone.
You probably won't have to check your site with all of the available evaluation tools out there, but it is a good idea to do so for the most common web browsers. Just as accessibility software makes it easier for people with disabilities to navigate the Internet, these tools make it easier for developers to ensure accessibility from the start. When you think you've mastered it, go back through the Section 508 compliance checklist to ensure you've met every goal.
The U.S. Department of Health and Human Services (HHS) also enforces Title II of the ADA relating to access to programs, services and activities receiving HHS federal financial assistance. This includes ensuring that people who are deaf or hard-of-hearing have access to sign language interpreters and other auxiliary aids in hospitals and clinics when needed for effective communication.

Federal law isn't the only consideration for businesses. Additionally, each state interprets the law differently. Consider the case against Netflix in 2012. Lawsuits were brought in federal court in Massachusetts and California. Netflix was accused of violating the ADA by not offering "closed captioning" options for its Internet streamed movies. Illustrating the complexity of this issue, the courts reached completely opposite decisions. Massachusetts held that Netflix must comply with the ADA, while the California court found that Netflix did not fall under the ADA's definition of "public accommodation."

The DOJ is currently working to release new technical standards for digital accessibility. The latter updates to the ADA guidelines will be in conjunction with the latest version of WCAG 2.1, which includes the most widely accepted digital accessibility requirements across the globe. If organizations want to overcome the current limitations of ADA guidelines, then they should follow the WCAG 2.1 checklist,11 as well as the suggestions provided by the ADA. The latter two steps, combined with the help of a trusted digital accessibility compliance platform,12 can help organizations achieve digital accessibility best in class standards throughout all of their digital formats and across all media.
The ADA guidelines provide the foundation that organizations need to achieve digital accessibility best approaches, however they are not exhaustive. They do not provide direction for all of the accessibility challenges that people with disabilities face. They also fail to provide detailed technical instructions. With these limitations in mind, there is a ray of hope.
This guidance document is not intended to be a final agency action, has no legally binding effect, and may be rescinded or modified in the Department's complete discretion, in accordance with applicable laws. The Department's guidance documents, including this guidance, do not establish legally enforceable responsibilities beyond what is required by the terms of the applicable statutes, regulations, or binding judicial precedent.