Public Address and Paging Systems
Remake batch 23: rewritten from scratch under the authoring cheatsheet with datasheet constraints; scope boundaries restated against the remade neighbors
Showing changes from Rev 2
to Rev 3
in Public Address and Paging Systems.
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title: Public Address and Paging Systems
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description: >
When to use: centralized amplifier-based or IP-networked audio distribution for routine announcements, background music, general intercom, and zone-based paging across buildings and campuses (schools, universities, offices, industrial facilities, warehouses, healthcare campuses, correctional facilities, and transportation terminals). Covers system architecture (70-volt constant-voltage analog vs. IP-networked audio), master and remote paging stations, amplifiers and digital signal processors, loudspeakers, supervision, intelligibility, and the interface to fire alarm voice evacuation.
− Not intended for: life-safety voice evacuation and emergency mass notification triggered by a fire alarm panel (use [[sync/mass-notification-systems]] and [[sync/fire-alarm-systems]] for the NFPA 72 Chapter 24 Emergency Communications System); fire alarm initiating devices and listed control units ([[sync/fire-alarm-systems]]); backbone pathways, conduit fill, and telecom rooms ([[sync/structured-cabling]]); cellular and public-safety radio coverage ([[sync/distributed-antenna-systems]]); security and access-control entrance intercoms; and auditorium sound reinforcement or AV presentation systems.
+ Not intended for: life-safety voice evacuation and emergency mass notification triggered by a fire alarm panel (use [[sync/mass-notification-systems]] and [[sync/fire-alarm-systems]] for the NFPA 72 Chapter 24 Emergency Communications System); fire alarm initiating devices and listed control units ([[sync/fire-alarm-systems]]); backbone cabling ([[sync/structured-cabling]]); pathways, conduit fill, and telecom rooms ([[sync/telecommunications-rooms-and-pathways]] and [[sync/raceways-and-conduit]]); cellular and public-safety radio coverage ([[sync/distributed-antenna-systems]]); security and access-control entrance intercoms; and auditorium sound reinforcement or AV presentation systems.
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- Life-safety voice evacuation and emergency mass notification initiated by a fire alarm control unit are covered by [[sync/mass-notification-systems]] and [[sync/fire-alarm-systems]]; NFPA 72 Chapter 24 Emergency Communications System requirements belong in those standards.
- Fire alarm initiating devices, annunciators, and listed fire alarm control units are covered by [[sync/fire-alarm-systems]].
−- Backbone cabling infrastructure, conduit fill, pathway design, and telecommunications and equipment rooms are covered by [[sync/structured-cabling]].
+- Backbone cabling infrastructure is covered by [[sync/structured-cabling]]; conduit fill, pathway design, and telecommunications and equipment rooms are covered by [[sync/telecommunications-rooms-and-pathways]] and [[sync/raceways-and-conduit]].
- Distributed Antenna Systems for cellular and public-safety radio are covered by [[sync/distributed-antenna-systems]].
- Security intercom and access-control intercoms at building entrances belong to the access control standard.
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−### For IP-networked or hybrid architectures, the audio transport protocol shall be coordinated with the network design so that the required VLAN, multicast, and QoS configuration is provisioned under [[sync/structured-cabling]].
+### For IP-networked or hybrid architectures, the audio transport protocol shall be coordinated with the network design so that the required VLAN, multicast, and QoS configuration is provisioned by the network owner; the passive cabling plant those devices connect through is governed by [[sync/structured-cabling]].
### The transport protocol is meaningful only once the architecture is chosen, and the choice then turns on what the owner's head-end platform and network already support, so the field carries no default. {note}
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### The Contractor shall furnish at least one spare amplifier module of each installed rating where N+1 redundancy is not provided.