2013 California Standards for Accessible Design Pocket Guide

1007.8.1 System requirements. Two-way communication systems shall provide communication between each required location and a central control point location approved by the fire department. Where the central control point is not constantly attended, a two-way communication system shall have a timed automatic telephone dial-out capability to an approved monitoring location. The two-way communication system shall include both audible and visible signals.

1007.8.1.1 Visible communication method. [DSA-AC and HCD 1-AC]  A button complying with Section 1138A.4 or Sections 11B-205 and 11B-309 _|Operable Parts|_ in the area of refuge shall activate both a light in the area of refuge indicating that rescue has been requested and a light at the central control point indicating that rescue is being requested. A button at the central control point shall activate both a light at the central control point and a light in the area of refuge indicating that the request has been received.