How many are there?: You see only four on the ice two linesman, two referees but the term officials also refers to the two goal judges at either end, the game timekeeper, penalty timekeeper and the video goal judge in the press box.
What are their roles?: All four on-ice officials can call infractions to stop play: icing, offsides, two-line passes, etc. The two referees call the penalties. The goal judges keep an eye on the pipes and punch the light switch when they see a puck completely cross the line. And the video judge helps settle disputed goals. That sounds easy, simply because how many disputes are there, right? In reality, he reviews each goal scored in a game, controversial or not. He only gets noticed during the former.
How do you become an official?: Most referees and linesmen start at the youth level. Should they continue to pursue the profession, they graduate to instructional and power-skating clinics held in the United States and Canada. From there, they are recruited by the minor leagues. When they reach the NHL, they begin the season by attending a one-week training camp.
Did you know?: Like players, officials are not immune to injuries. As an insurance policy, the NHL has an emergency referee and linesman at every playoff game.
Compiled by Tim Sullivan