A National Hockey League game can be an exciting event, but something is done to the hockey pucks that keep the games from becoming a little too exciting.

A hockey puck is made of vulcanized rubber, and rubber, as you know, is bouncy, especially at room temperature or warm. That is why the NHL uses frozen hockey pucks for all its games so the pucks aren’t too bouncy, and the pucks (or biscuits as they are sometimes known) are kept in a freezer in the penalty box. The pucks are kept at a temperature between 14 degrees Fahrenheit and 20 degrees Fahrenheit to make sure they are frozen before they are put into play.

NHL rules state that the home team will be responsible for keeping game pucks frozen and that they should be kept in the penalty box under the watchful eye of an official or other attendant. A home team does this by transporting fifteen pucks from a freezer of the home team to the penalty box cooler. They even transport them in another cooler. At the beginning of the second and the third period of the game, fifteen more pucks are transported from the home team’s freezer to the penalty box cooler.

Things get even more specific when a puck is in play. After a puck has been used for more than two minutes, it gets replaced with a new frozen puck so that consistency is guaranteed no matter at one point a player gets in the game. It’s up to a linesman (a referee official) to make the exchange from a used puck to a new frozen puck, and they usually do that before the next face-off. If a used puck is returned to the penalty box freezer attendant, it is not used again and is returned to the home team’s freezer after the period ends. Pucks are also exchanged during commercial time-outs in the same way. About 25-30 pucks are used on average in a typical NHL game. Look for the exchange the next time you happen to watch a hockey game.

Bonus Hockey Puck Facts:

The fastest ice hockey slapshot in competition was done by Denis Kulyash in the Russian Continental Hockey League in 2011 and was clocked at a speed of 110.3 mph . The previous record was 105.4 mph by Zdeno Chara of the Boston Bruins during the All-Star skills competition of the National Hockey League in 2009.

There was one time when a different sort of hockey puck was used in NHL games. It was called the FoxTrax puck, and it was used in the 1995-1996 season. The Fox Network developed the puck that was supposed to make viewing its movement easier. It was composed of a battery and small computer at its center along with infrared emitters that pulsed and these pulses were picked up by sensors around the rink. The movement was processed by a computer which put a blue halo around the puck. When the puck speed went above 50 mph it had a red trail, when it went over 75 mph it changed to green. The pucks only lasted about 10 minutes on battery power and each one cost around $400. The glowing puck experiment came to an end when the Fox Network didn’t renew their NHL contract after the 1998-99 NHL season.

Sources: NHL Officials, SB Nation, Hockey World, Guinness Book, Made How

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