The phone is to the left of the first guard.
  Clear the area with two guards to reach a walkway leading to two locked doors. 
  The phone is on the walkway between both doors.
  Continue forward after entering the office area. The phone is on the desk on 
  the left.
  Enter the room with the Access Elevator switch. The phone is in the closed 
  office next to this room on a desk.
  Leave the falling elevator. The phone is on a crate to the right.
  Climb out of the elevator. From this floor, go down the stairs to the floor 
  below. The phone at the bottom of the stairs.