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This page shows Department of Transportation content pertaining to a specific tag. If you cannot find what you’re looking for on this page, please use the search box in the top right of our website.
This Web page includes a list of time zone proceedings and links to the final rules from those proceedings. To view the final rule in each proceeding, click on the date next to the description of the proceeding you would like to view.
Under the Uniform Time Act, as amended, States may exempt themselves from observing Daylight Saving Time by State law. If a State chooses to observe Daylight Saving Time, it must begin and end on federally mandated dates.
Under Federal law, there are two ways in which an area in the United States can be moved from one time zone to another.
The U.S. Department of Transportation (DOT) oversees the Nation's time zones. The oversight of time zones was assigned to DOT because time standards were first instituted by the railroad industry.