New rules took effect just before midnight Tuesday requiring millions of travelers in the United States to wear masks on airplanes, trains, buses, ferries, taxis and ride-share vehicles and in airports, stations, ports and other transit hubs. … Nearly all U.S. travel is covered by the rules, but people in private cars and solo truck drivers are exempt. The order requires all passengers two and older to wear masks but travelers can avoid wearing masks if they have a disability.