Hoping to clarify its rules in the wake of a CDC announcement about mask wearing, the MBTA on Friday reminded its customers that face coverings are still required “while onboard vehicles, in stations and facilities, on platforms and bus stops, and anywhere within the MBTA system for all riders, including those who have been fully vaccinated.”

The T cited the Centers for Disease Control’s statement that “fully vaccinated people can resume activities without wearing a mask” while also pointing out that the CDC guidance “also notes that fully vaccinated individuals are still required to wear a mask on buses, trains, and other forms of public transportation.”

In a press release, the T said, “MBTA riders are reminded that federal and state regulations continue to require face coverings while riding MBTA vehicles and within the MBTA system, regardless of a person’s vaccination status. This includes outdoor bus stops and all outdoor platforms for the Commuter Rail, subway, and trolley systems. Those who refuse to comply with the MBTA’s face covering requirement may be denied boarding of or be removed from MBTA vehicles and the system.”