From NFPA 101, Life Safety Code, 2018 edition:
18.104.22.168.5 The area of refuge shall be provided with a two-way
communication system for communication between the area of
refuge and a central control point. The door opening to the
stair enclosure or the elevator door and the associated portion
of the area of refuge that the stair enclosure door opening or
elevator door serves shall be identified by signage. (See
Why does this section not make specific reference to NFPA 72, specifically Section 24.10?