In a memo distributed Wednesday, teams also received details on fan and media access to training camp and preseason games as well as a fine schedule for players who violate specific protocols.
The NFL decided earlier this year not to make vaccines mandatory for players, and a number of high-profile players have said in recent weeks that they have not yet received a shot.
The memo also directed teams to keep fans a minimum of 20 feet from players and key staff members during training camp.