evidence: Section 1. Policy. Science-based public health measures are critical to preventing the spread of coronavirus disease 2019 (COVID-19) by travelers within the United States and those who enter the country from abroad. The Centers for Disease Control and Prevention (CDC), the Surgeon General, and the National Institutes of Health have concluded that mask-wearing, physical distancing, appropriate ventilation, and timely testing can mitigate the risk of travelers spreading COVID-19. Accordingly, to save lives and allow all Americans, including the millions of people employed in the transportation industry, to travel and work safely, it is the policy of my Administration to implement these public health measures consistent with CDC guidelines on public modes of transportation and at ports of entry to the United States. Sec. 2. Immediate Action to Require Mask-Wearing on Certain Domestic Modes of Transportation. (a) Mask Requirement. The Secretary of Labor, the Secretary of Health and Human Services (HHS), the Secretary of Transportation (including through the Administrator of the Federal Aviation Administration (FAA)), the Secretary of Homeland Security (including through the Administrator of the Transportation Security Administration (TSA) and the Commandant of the United States Coast Guard), and the heads of any other executive departments and agencies (agencies) that have relevant regulatory authority (heads of agencies) shall immediately take action, to the extent appropriate and consistent with applicable law, to require masks to be worn in compliance with CDC guidelines in or on: