Penalties
During a game, penalties are assessed when players commit a significant foul against an opponent or official. Penalized players are required to leave the ice and spend time in the penalty box. This leaves the team shorthanded for the duration of the penalty (or until the team with the advantage scores a goal). The length of the penalty is determined by the seriousness of the infraction. Only two minor penalties can be served at the same time, so if a team accumulates more than two, the additional ones are served immediately after the earlier ones expire. If a goal is scored on a team that is serving two penalties, only one of the penalized players returns to the game, leaving the team still shorthanded.

Minor penalties, which last two minutes, are generally assessed to players who illegally impede an opponent’s progress by tripping or holding. Minor penalties may also be called in several other instances: when a player does something that might injure an opponent, such as using the stick illegally; when players or teams intentionally delay a game; or when a team has too many players on the ice.

A major penalty lasts five minutes. Major penalties are assessed when a player commits a more serious foul, such as fighting. Some offenses are serious enough to be considered match penalties, which mean ejection from the remainder of the game and the possibility of suspension from further competition. In this case the team plays shorthanded for five minutes and then returns to even strength, without the services of the ejected player.

Players or teams can be assessed misconduct penalties for showing a lack of respect for an opponent or official, or for repeatedly ignoring an official’s instructions. A teammate is substituted on the ice, and the penalized player may not rejoin the game for ten minutes. A game misconduct penalty is assessed to a player who uses excessive and dangerous physical force, such as by checking from behind or head-butting. In the case of such penalties, which usually indicate intent to injure another player, the penalized player is banned from returning for the duration of the game, and the team must play shorthanded for five minutes. Goalies do not serve minor, major, or misconduct penalties. Instead, their penalties are served by a teammate that was on the ice at the time of the infraction. Goalies are, however, required to leave a game when they are assessed any type of penalty that calls for their removal from the contest.

When a penalty or series of penalties leaves one team with more skaters on the ice than its opponents, the team with the player advantage is said to have a power play. The team with the advantage attempts to control the puck with quick passes, trying to create open shots on goal. The disadvantaged team often retreats into a square formation to defend. Players shift to the puck’s movement and try to prevent open shots. This is called penalty killing. During a power play, defensive players rarely chase errant shots or attack the opponent’s goal. The power play ends when penalty time expires or when the team with the advantage scores a goal.