The NHL has followed the NBA in revising its virus protocols early in the season as a response to COVID-19 problems cropping up around the league.

Glass panels have been removed from behind benches for better air flow, players and coaches are not allowed at the arena until 1 hour and 45 minutes before the game unless they're getting treatment for injuries and all meetings must be virtual.

The 31 teams were also told to space out locker rooms more to provide 6 feet of space between people. Deputy Commissioner Bill Daly confirmed the updates Thursday in an email to The Associated Press.

The league is not yet considering adding a daily rapid test to go along with PCR testing, like the NBA did. PCR tests are considered to be more accurate, but there's a 12-24 hour turnaround on results.

The moves were made as the NHL sees some concerning trends: 40 players were on the COVID-19 unavailable list and four teams were idled because of varying degrees of outbreaks.

In the first three weeks of the season, approximately 90 players have appeared on the list, which can include a positive test result unconfirmed or confirmed, symptomatic isolation, high risk close contact or quarantine for travel purposes.

Vegas, New Jersey, Buffalo and Minnesota are currently paused with at least one player on the list. The Wild added five new players to the list Wednesday and the Sabres said Thursday that 61-year-old coach Ralph Krueger had tested positive and will enter virus protocol immediately. Vegas had three coaches in the protocol last week.

So far, 22 games have been postponed affecting 16 of the league's 24 U.S.-based teams. Only one of the 40 players currently on the COVID list is from a Canadian team, and that is because Pierre-Luc Dubois is in quarantine after a trade from Columbus to Winnipeg.

After completing last season in quarantined bubbles in Toronto and Edmonton, Alberta, the NHL planned for 2021 outside a bubble with 12 different protocol documents spanning 213 pages. The rules call for masks everywhere at team facilities, including locker rooms, and coaches and backup goaltenders wearing them on the bench.

Players, coaches and staff are also limited to the hotel and rink on the road.

"I think the protocols are appropriate," Philadelphia general manager Chuck Fletcher said Tuesday. "These are difficult times. Look, you can do everything right and still contract COVID. I think we're all trying to be careful. I think the players recognize how fortunate we are to be back playing, playing games, competing for a Stanley Cup and earning a paycheque."

-AP Sports Writer Dan Gelston contributed.