The Federal Aviation Administration is responsible for the safety of civil aviation within the United States. It's major roles include regulating civil aviation to promote safety, encouraging and developing civil aeronautics, including new aviation technology, developing and operating a system of air traffic control and navigation for both civil and military aircrafts, developing and carrying out programs to control aircraft noise and other environmental effects of civil aviation, regulating U.S. commercial space transportation.
As part of their role, the FAA sets the standards on markings and lighting of towers and other obstructions. Below is a brief guideline of how the code affects the tower industry:
For more information on the standard: