The NBA and its players union updated COVID-19 health and safety protocols on Tuesday, adding tougher new rules in the wake of increasing player cases and game postponements.

NBA and its National Basketball Players Association officials talked on Monday and NBA team owners spoke on Tuesday to approve tighter measures for players for home and road activities, as well as in using face masks.

The league announced a fifth game postponement on Tuesday, the third involving a Boston Celtics team depleted by COVID-19 testing and contact tracing, and vowed to amend measures as needed as the pandemic evolves and the number of players on the virus reserve list increases.

The new measures were imposed "in response to the surge of COVID-19 cases across the country and an uptick among NBA teams requiring potential player quarantines," a league statement said.

For at least the next two weeks, players and team staff are required to remain at their residence at all times when the club is at home except to attend team-related activities, exercise outside or perform essential activities, except in extraordinary circumstances.

Interactions away from the NBA club are limited to household members, family and any personal staff working regularly in the home.

When the club is on the road, players and team staff are banned from leaving the hotel, except for team activities or emergencies, or interacting with non-team guests.

Any pre-game meetings in the locker room are limited to no more than 10 minutes and all in attendance must wear a face mask.

All other meetings must be on the court, an NBA-approved area or at the arena in a room large enough to allow for social distancing with masks a must.

Teams must create a seating plan for flights so players with seats nearest each other on the bench for NBA games are nearest to each other on plane flights.

Any hotel treatment sessions, including physical therapy and massages, must take place in a ballroom or other area allowing 12 feet (3.66 meters) between each station, with face masks and face shields required for all involved.

Players cannot arrive at arenas more than three hours before tip-off.

Any interactions between players before and after games are limited to elbow or fist bumps with social distancing maintained as much as possible and "extended socializing" to be avoided.

Players must wear face masks on the bench at all times and must enter and exit games through "cool down chairs" at least 12 feet from the bench with chairs six feet (1.83 meters) apart – an area where masking is not required.

After the cool-down period, a player must don a mask and return to his assigned seat.

Masks are required in locker rooms, at strength and conditioning activities and for travel with anyone other than a household member.

Coaches and other team staff must wear face masks at all times during games.

Anyone regularly visiting a player's home for a professional activity, such as a trainer, must undergo COVID-19 testing twice a week.

For teams with a positive player or high-risk staff member case, the NBA can require players and staff to undergo five consecutive days of twice-a-day lab COVID-19 testing in addition to usual daily testing.