How long are periods and intermissions, and how do time-outs work for the timekeeper?

From Rule 6.17 of the Hockey Canada Playing Rules 2026-2028:

• Periods: three 20-minute periods of regulation playing time, with approximately a 10-minute intermission (when the ice is flooded) between each period, is the maximum time allowed for each game. Members and leagues may make their own rules on regulation time, as long as it does not exceed these guidelines.
• Ends: teams change ends after each regulation period and each overtime period (except as stated in the Tied Game rule).
• Delay late in a period: if an unusual delay occurs within five minutes of the end of the first or second period, the referee may order the next regular intermission immediately. The rest of the period is played afterwards with the teams defending the same goals.
• Time-outs: each team may take one 30-second time-out in regular playing time or overtime, during a normal stoppage. A player designated by the coach tells the referee, and the referee reports the time-out to the Game Timekeeper, who is responsible for signalling when it ends.
• A team may call a time-out up to the point the official blows the whistle to start the face-off procedure.
• Both teams may take their time-outs during the same stoppage. Once one team has called its time-out, the second team must say it wants one during the same stoppage before the first 30 seconds are over.
• The time-out rule is permitted in minor and female stop-time games where the local Member approves. It must be used in Hockey Canada minor and female regional and national championships.