Hospital PA Systems: Zoning That Doesn't Disturb Patients
A hospital PA system must reach every public area yet stay quiet on the wards. This guide covers zoning, paging priority, emergency code announcements, EVAC, and how PA differs from nurse call.
A hospital PA system is a public address system designed to reach every public area while staying quiet in patient areas. It zones the building by how each department is used, ranks announcements by priority, and handles emergency code announcements and fire evacuation (EVAC) in a single system. Unlike an office building or a shopping mall, where coverage is the main goal, a hospital has to balance fast staff communication against patient rest, which facility managers and procurement officers should understand before writing a specification.
How does a hospital PA system differ from an ordinary building?
The main difference is that a hospital has three groups of building users who need different sound at the same time: patients, who need quiet to recover; relatives and visitors, who need information such as queue calls and visiting hours; and staff, who need a fast, reliable communication channel around the clock. One set of speakers at one volume for the whole building therefore cannot work. On top of that, a hospital never closes, so installation and maintenance must be possible without shutting down the whole system, and evacuating patients who cannot move on their own depends on staged announcements. The design therefore has to start from how each department is used, not from an equipment model.
How should quiet zones and public zones be divided?
A practical approach is to split the building into two broad groups first, then subdivide by department. The first group is the quiet zones: inpatient wards, intensive care units (ICU), operating theatres, and recovery rooms. These areas should receive no music or general announcements, only emergency announcements and messages that directly concern that area. Their volume should be set lower than elsewhere, and speakers belong at the nurse station and along corridors rather than inside patient rooms. The second group is the public zones: the outpatient department (OPD), the reception hall, cashier and pharmacy counters, the cafeteria, and the car park. These areas need clear, complete coverage and may carry soft background music; the car park should use horn or weatherproof speakers. Then subdivide by floor or department so that staff can be paged within one department without disturbing another. Every zone's volume should be independently adjustable, and in public zones where background noise changes through the day, consider ambient noise sensing that adjusts volume automatically.
What is paging priority?
Priority is the rule that decides, when several sources want to reach the same zone at the same time, which one is heard and which is ducked or cut temporarily. A hospital should define several priority levels: evacuation and alarm announcements triggered by the fire alarm system must sit at the top and override everything; next come medical emergency code announcements from designated paging points; then general announcements such as staff paging and queue calls; with background music and scheduled automatic announcements at the bottom, ducked whenever anything else is announced. Beyond levels, you also need to define which paging point may reach which zones: for example, the information desk may page only the public zones, while the emergency command centre may reach every zone including the quiet ones. Write this permission and priority table into the specification from the start so that configuration and acceptance testing match.
How should emergency code announcements be designed into the system?
Many hospitals summon emergency teams with codes over the PA, such as a code for cardiac arrest or a code for fire. The names of the codes and their meanings are set by each hospital under its own internal rules, and the relevant requirements and standards should be checked. From the hospital PA system's point of view, what has to be prepared is:
- an emergency paging point that can be reached instantly, such as at the call centre or the main nurse station, without stepping through several zone selections
- pre-recorded messages that play at the press of a button, so the announcement is clear and consistent every time
- preset destination zones, for example a third-floor cardiac arrest code that goes only to the staff zones and corridors of that floor, not to the outpatient hall
- an event log of who announced what and when. Designed this way, the medical team gets the information within seconds while patients and relatives in the public areas are not alarmed unnecessarily.
What is special about an EVAC system in a hospital?
An evacuation sound system (EVAC) is the part of the PA that works with the fire alarm system to give spoken evacuation guidance instead of a bell alone. A hospital adds three further concerns. First, many patients cannot move on their own, so evacuation is usually phased: people are moved to a safe area on the same floor first. The system must therefore play different messages in different zones at the same time, for example an evacuation order in the affected zone and a stand-by message in the neighbouring zones. Second, the system must keep working when mains power fails, so it needs backup power, automatic monitoring of speaker lines and amplifiers, and a fault alert when something is wrong, which is the guidance the EN 54 standard for voice alarm systems sets out. Third, the system must always be able to reach the quiet zones in an emergency, even when general announcements to those zones are muted. As for which legal requirements apply to which building type, check the requirements and standards that apply to your building directly.
How does PA differ from nurse call, and can the two be connected?
A nurse call system is a separate system that lets a patient call a nurse from the bedside to the nurse station. It is point-to-point communication from one patient to their own care team, whereas a PA system is one-to-many communication. The two answer different needs and should not be substituted for each other: paging a nurse to a patient room over the PA disturbs the whole ward, and a bedside call system cannot announce an emergency across the building. What you can do is plan both systems on infrastructure that supports each other, for example sharing the LAN on separate VLANs, sharing the same backup power, and specifying that the PA can accept a trigger signal from another system in future. Even if the two are procured under different projects, the designer should see the whole building at once so that cabling is not duplicated.
Checklist before writing a hospital PA specification
Before contacting a hospital PA designer or installer, prepare:
- floor plans of every level marked as quiet zone or public zone
- a list of paging points, who announces, from where, and to which zones
- the list of emergency codes and pre-recorded messages you need
- details of the existing fire alarm system and its interface point
- existing equipment to be reused or replaced
- an installation plan that does not interrupt services, such as working one floor at a time. On technology, for a small single building a 100V speaker-line system is cost-effective and easy to maintain, while for a multi-building hospital or one planning new wings an IP system adds zones and centralises control more flexibly. On budget, a medium system of 3–6 zones with 20–50 speakers usually starts at around 200,000 baht, and a large system of 6 or more zones with 50 or more speakers starts at around 500,000 baht, with the actual price depending on the site survey and the final design. VAN INTERTRADE was founded in 1986, installs and services nationwide, is a registered e-GP vendor, helps draft the TOR, specification, and BOQ, and offers a free consultation and site survey.
Frequently asked questions
Should PA speakers be installed inside patient rooms?
Generally no. Wards and ICUs are quiet zones: place speakers at the nurse station and along corridors, set the volume low, and route only emergency announcements or messages that concern that area. Music and general announcements should be confined to public zones such as the OPD and the reception hall.
Can a PA system replace the bedside call system?
No. A bedside call system is point-to-point communication from a patient to their care team, while a PA system is one-to-many. They serve different purposes, but they should be planned to share infrastructure such as the LAN and backup power so that cabling is not duplicated.
How should paging priority be set in a hospital?
Set several priority levels, with emergency announcements at the top: evacuation and alarm announcements from the fire alarm system, followed by medical emergency codes, then general announcements, with background music at the bottom. A higher level always ducks or cuts a lower one, and you should also define which paging point may reach which zones.
Does a hospital need an EVAC system?
An EVAC system enables phased, spoken evacuation guidance and keeps working during a power failure, which matters greatly in a building where patients cannot move on their own. As for which legal requirements apply to which building type, check the requirements and standards that apply to your building directly.
Should a hospital PA system be 100V or IP?
For a small single building a 100V system is cost-effective and easy to maintain; for a multi-building hospital or one planning to expand, an IP system adds zones and centralises control more flexibly. The actual price depends on the site survey and the final design.