How did the Rec Center glass shatter during Thursday's Section 1 championship game?

Mar. 2—By now, you've likely seen the photos and videos that went viral — well, semi-viral; as viral as an incident at a boys hockey game in southern Minnesota can.

After Rochester Century/John Marshall junior forward Ole Fevold scored a goal with 12 minutes, 32 seconds remaining in the second period, he and his teammates skated toward the Panthers student section in the on the east side of the Rochester Recreation Center, just to the left of the Century/JM bench.

As the players huddled, the celebrate, their fans were understandably excited, too, and hopped over the ropes that were in place to block off the front two rows of bleachers. Fevold's goal had given the Panthers a 2-0 lead against five-time defending Section 1, Class 2A champion Lakeville South in the section championship game.

As the students celebrated by pounding on the glass — as happens at most hockey games after a goal or a big hit — one pane shattered, then a second pane shattered a split second later.

One fan had to go to the ER due to cuts from the shattered glass. At least four others were treated by the on-site athletic trainers from both teams.

Rec Center officials were able to get the shattered glass scooped into a wheelbarrow — which was skated off the ice by Lakeville South goalie Carson Hauger, to a round of applause from fans on both sides of the arena — get the panes replaced (the only panes available in the moment that would fit were shorter than the originals, so Thursday's game was resumed with the shorter panes in place) and the ice vacuumed and resurfaced within 38 minutes. Fevold's goal was scored at 7:45 p.m. Play resumed at 8:23 p.m.

Why did the glass shatter, seemingly so easily, by fans hitting it, when pucks and player slam into it all game long?

The quick answer is, the Rec Center glass is tempered glass (also known as safety glass), not plexiglass.

Many hockey arenas around the country have gone to tempered glass for two reasons: First, tempered glass provides better visibility for fans than plexiglass, which can chip over time from pucks shot at high speeds.

Second, tempered glass is much stronger than standard glass, which, when broken, can break into dangerously sharp shards. Tempered glass, while still sharp, is designed to shatter into small chunks, as it did at the Rec Center on Thursday.

According to article, tempered glass is created by a process of successively heating glass to more than 600 degrees Celsius, then rapidly cooling it by blasting it with high-pressure air, in order to strengthen the glass. The flat plane of the glass becomes very resistent to hits, but can be easily shattered when there is an extreme change in temperature or due to a simple tap in a spot where there was a tiny abnormality in the manufacturing process.

Thursday was the second time this season that the Century/JM team has had a pane of glass shatter during one of its games. It also happened prior to a game at Graham Arena IV earlier this season, when a player jumped into the glass as part of his routine at the end of warmups.

The Panthers kept up their momentum after the 38-minute delay, scoring two more times in the second period en route to a 4-1 victory and their first trip to the state tournament since 2009. They'll play in the first Class 2A state quarterfinal on Thursday, at 11 a.m. against No. 2-seeded Chanhassen.

"We actually kept calm, just sat down, then walked around a little; we knew we had to be ready to go after it was done," Century/JM junior goalie Kyle Lappi said of the lenghty delay in Thursday's game. "I think just our hustle and grit really did it for us (Thursday) night. We were getting pucks deep and kept battling hard; that's what really did it for us."