The NFL has expanded its mandate for mask usage on the sideline and is threatening discipline for those who violate the league’s updated COVID-19 protocols.

The league told teams in a memo on Monday that players who are not substituting or preparing to enter the field of play and are not wearing their helmets will be required to wear a mask or a double-layered gaiter on the sideline, starting this week.

Play-callers now must wear a mask even if they have a face shield. Postgame interactions between players and staff will be limited. Also, players and team personnel must wear masks and may briefly greet opponents after games.

“Players who fail to wear masks on the sidelines will be subject to discipline,” the league said in its memo. “Clubs are required to enforce these rules. Violations by players and/or staff will result in accountability measures being imposed upon the club. It is strongly recommended that each club designate one or two individuals in the bench area to ensure compliance with these rules.”

The league is also reducing the maximum number of players that may travel to 62. Any player who travels to a game, including injured who are not eligible to play, will count against the 62-player maximum.

Starting in Week 13, all members of a team’s traveling party are required to wear N95 or KN95 masks on team planes and buses.

Starting Nov. 30, access to a team’s training facility will be limited to essential football and support personnel during the times players and coaches are present.

The league is also limiting the number of specialists such as chiropractors, massage therapists and barbers that may enter a club’s facility each week to five.