Puck: dimensions, material and why it is frozen

Dimensions and material

The puck is the object of play in ice hockey. Its dimensions are set out practically identically in the IIHF and NHL rulebooks:

The edge is usually textured so the stick grips better. The faces often carry league or tournament logos.

Why are pucks frozen?

This is one of the most common questions from ice hockey newcomers, and the answer has to do with physics. At room temperature, rubber is relatively elastic. A warm puck bounces when it hits the ice, a stick or the boards – it "hops" and rolls onto its edge more easily. This makes passes and shots unpredictable.

When the puck is frozen, the rubber loses much of its elasticity. The frozen puck

• stays flatter on the ice,
• glides more evenly and faster,
• rebounds less strongly,
• can be received and passed more precisely.

That is why, in professional leagues, pucks are stored in cool boxes or freezers before the game and regularly swapped for fresh, cold pucks during play. A puck warms up relatively quickly during a game through friction, impacts and the air in the arena.

From ball to disc

Some of the first ice hockey games in the 19th century were played with balls that bounced over the boards into the crowd. For the match in Montreal in 1875, considered the first modern ice hockey game, a flat wooden disc was therefore used. Later rubber took over, first made of two halves glued together, then of one piece.

Where the name "puck" comes from has not been conclusively established. A common explanation derives it from the Scottish Gaelic "puc" (to strike, to push), as used in the related sport of hurling.

Special pucks

• Training pucks: heavy pucks (about twice as heavy) train the wrists and shooting power.
• Light pucks: blue pucks are lighter and intended for children in youth hockey.
• Street hockey pucks: made of plastic with glide nubs, for asphalt.
• Sensor pucks: in some professional leagues, pucks contain transmitters that record position and speed for TV graphics and statistics.

How fast can a puck go?

Hard slap shots by professionals reach well over 150 km/h. In NHL skills competitions, values of more than 170 km/h have been measured for years. That is why goaltender equipment, glass and safety nets behind the goals are indispensable.

Where to see pucks live

You can find games from the DEL, DEL2 and other leagues in the ice sports calendar. What the ice resurfacer does between periods so that the puck glides optimally is explained in the article ice preparation.