Fully vaccinated NFL players and staff will no longer be required to wear masks at team facilities, the league informed clubs in a memo Friday. The policy change is effective immediately.

The NFL's health and safety department made the decision after the Centers for Disease Control and Prevention updated its COVID-19 mask guidelines for the United States on Thursday. People are considered fully vaccinated if 14 days have passed since their second shot of the Pfizer and Moderna vaccines or their single shot from Johnson & Johnson.

The league is encouraging but not requiring players to get vaccinated. Non-players are expected to be vaccinated unless they have a medical or religious exemption. Those who are not vaccinated will not be allowed to interact with players.

Cleveland Browns coach Kevin Stefanski learned of the news on the practice field during rookie camp Friday. The reigning NFL Coach of the Year was able to take his mask off for the first time as a head coach.

"It felt pretty good," Stefanski said. "There were some people I didn't realize what they looked like."

According to the memo, the NFL expects additional modifications to come that will reflect "the greatly reduced risk of viral infection and transmission in fully vaccinated individuals."

The Associated Press contributed to this report.