There have been some notable cases regarding the ADA. For example, two major hotel room marketers (Expedia.com and Hotels.com) with their business presence on the Internet were sued because its customers with disabilities could not reserve hotel rooms, through their websites without substantial extra efforts that persons without disabilities were not required to perform. These represent a major potential expansion of the ADA in that this, and other similar suits (known as "bricks vs. clicks"), seeks to expand the ADA's authority to cyberspace, where entities may not have actual physical facilities that are required to comply.
This portion of the law is regulated and enforced by the U.S. Equal Employment Opportunity Commission. Employers with 15 or more employees must comply with this law. The regulations for Title I define disability, establish guidelines for the reasonable accommodation process, address medical examinations and inquiries, and define “direct threat” when there is significant risk of substantial harm to the health or safety of the individual employee with a disability or others.
Once you have been hired and started work, your employer cannot require that you take a medical examination or ask questions about your disability unless they are related to your job and necessary for the conduct of your employer's business. Your employer may conduct voluntary medical examinations that are part of an employee health program, and may provide medical information required by State workers' compensation laws to the agencies that administer such laws.