stylistic:tone, structural:summarization, linguistic:voice_change
Fire service

Depending on the location of the elevator, fire service code will vary state to state and country to country. Fire service is usually split up into two modes: phase one and phase two. These are separate modes that the elevator can go into.

Phase one mode is activated by a corresponding smoke sensor, heat sensor, or manual key switch in the building. Once an alarm has been activated, the elevator will automatically go into phase one. The elevator will wait an amount of time, then proceed to go into nudging mode to tell everyone the elevator is leaving the floor. Once the elevator has left the floor, depending on where the alarm was set off, the elevator will go to the fire-recall floor. However, if the alarm was activated on the fire-recall floor, the elevator will have an alternate floor to recall to. When the elevator is recalled, it proceeds to the recall floor and stops with its doors open. The elevator will no longer respond to calls or move in any direction. Located on the fire-recall floor is a fire-service key switch. The fire-service key switch has the ability to turn fire service off, turn fire service on or bypass fire service. The only way to return the elevator to normal service is to switch it to bypass after the alarms have reset.

Phase-two mode can only be activated by a key switch located inside the elevator on the car operating panel. This mode was created for firefighters so that they may rescue people from a burning building. The phase-two key switch has three positions: off, on, and hold. By turning phase two on, the firefighter enables the car to move. However, like independent-service mode, the car will not respond to a car call unless the firefighter manually pushes and holds the door close button. Once the elevator gets to the desired floor it will not open its doors unless the firefighter holds the door open button. This is in case the floor is burning and the firefighter can feel the heat and knows not to open the door. The firefighter must hold the door open button until the door is completely opened. If for any reason the firefighter wishes to leave the elevator, they will use the hold position on the key switch to make sure the elevator remains at that floor. If the firefighter wishes to return to the recall floor, they simply turn the key off and close the doors.

In the UK and Europe the requirements for firefighters lifts are defined in the standard EN81-72.