On May 13, the Centers for Disease Control and Prevention issued guidance that fully vaccinated individuals can resume indoor and outdoor activities without wearing a mask or social distancing. However, those traveling planes, trains, buses, and other forms of public transportation still have to wear masks, according to the CDC. And the Port Authority of Allegheny County is reminding Pittsburgh-area riders of these requirements, even for fully vaccinated individuals. “We've received a few questions about the updated CDC guidelines and wanted to make sure it's absolutely clear for you, for our employees, and for the person sitting next to you: Masks are still required to be worn on public transit vehicles,” tweeted the official Port Authority account on May 13.