A Fire and Emergency Services (FES) or evacuation paging system must be installed and implemented for life safety or security announcements.

A Fire and Emergency Services (FES) or evacuation paging system must be installed to provide emergency announcements and messages in accordance with public law in response to 11 September 2001 and local building codes. Local building codes have for years required facilities to provide evacuation and life safety sound systems. These systems may be required by federal or public law in the wake of 9/11/2001. In addition to life safety announcements about an evacuation or emergency condition within a facility, these systems may be used for security alerts; for example, instruct site personnel to be on the lookout for an intruder or other unauthorized person.