A voice evacuation system broadcasts recorded and live spoken instructions through zoned loudspeakers when the fire alarm operates, so occupants hear what is happening and where to go instead of a tone alone. Saudi projects usually need one in large, tall or crowded buildings and wherever evacuation is phased, as set by the adopted code, Civil Defense and the consultant’s specification.
Key takeaways
- A tone warns; a voice message directs. Voice matters most where occupants do not know the building or only some zones evacuate at a time.
- NFPA 72 covers in-building fire emergency voice/alarm communications systems (EVACS) in its emergency communications chapter; EN 54-16, EN 54-24 and BS 5839-8 apply on European and British specifications.
- Loud is not intelligible. Speech intelligibility, commonly measured with the speech transmission index (STI) of IEC 60268-16, is the real test.
- With partial evacuation or relocation, NFPA 72 requires pathway survivability, which can mean 2-hour rated cables or enclosures.
- A combined public address and voice alarm (PA/VA) system works if emergency messages override paging and music and the equipment is approved for voice alarm use.
In this article
- What is a voice evacuation system and how does it work?
- When do Saudi projects need voice evacuation?
- Sounders, dedicated voice evacuation or combined PA/VA?
- Speech intelligibility: the real test
- Survivability, secondary power and cables
- Designing and installing a voice evacuation system: step by step
- Common site mistakes
- Inspection, testing, maintenance and cost
- How AZEIDK helps
- FAQ
What is a voice evacuation system and how does it work?
In a small building with familiar occupants, a tone is enough. In a multi-level mall, a busy hotel or a crowded terminal, people who hear a tone often stop to wonder whether it is a drill. A clear spoken message removes that hesitation.
When a detector or manual call point operates, the fire alarm control panel signals the voice alarm controller according to the cause and effect matrix. The controller broadcasts an evacuate message in the affected zones and an alert message elsewhere.
Main components
- Voice alarm control and indicating equipment manages messages, zones and priorities and monitors faults. EN 54-16 covers this equipment, but not the audibility or intelligibility of the installed system.
- Amplifiers are sized to each zone’s loudspeaker load, with standby capacity as the approved design requires.
- Loudspeakers follow EN 54-24 on European-specified projects: type A for generally indoor use and type B for generally outdoor use.
- Fire microphone, secondary power and fire alarm interface handle live announcements, power failure and the choice of message for each zone.
When do Saudi projects need voice evacuation?
The requirement follows occupancy classification, height, area and occupant load under the Saudi Fire Protection Code (SBC 801) and the Saudi Building Code (SBC 201), plus Civil Defense requirements and the consultant’s specification. The 2024 edition of the Saudi Building Code came into effect on 30 June 2025.
The Saudi Building Code is based on the International Codes (I-Codes) of the International Code Council (ICC). In that model, for example, the fire alarm in assembly occupancies with 1,000 or more occupants initiates an emergency voice/alarm communication system. Whether SBC 801 applies the same trigger to your building is for the consultant and Civil Defense to confirm.
In practice, voice evacuation is commonly specified in malls and commercial centers, hotels, hospitals that evacuate in stages, high-rise towers, airports and large assembly venues.
Chapter 24 of the NFPA 72 fire alarm code covers one-way systems, including fire voice/alarm and mass notification, and two-way systems. Fire alarm signals traditionally have top priority, but a risk analysis can let mass notification take priority. The current edition is NFPA 72 2025; the edition that applies in Saudi Arabia is set by SBC 801 and Civil Defense.
British-specified projects use BS 5839-8, the code of practice for voice alarm systems; its October 2023 edition added a recommendation on loudspeakers in disabled refuges and a cybersecurity clause. Our EN 54 standard guide explains the European equipment parts.
Sounders, dedicated voice evacuation or combined PA/VA?
The right choice depends on the building, its users and the adopted code:
| Criterion | Sounders and beacons | Dedicated voice evacuation | Combined PA/VA |
|---|---|---|---|
| Message | Warning tone and flashing light only | Recorded and live speech | Emergency speech plus daily paging and music |
| Phased evacuation | Limited; tones give no instructions | Different messages per zone | Different messages per zone |
| Typical buildings | Small and medium buildings with familiar occupants | Large, tall and crowded buildings | Malls, hotels and airports that need daily paging |
| Watch point | Does not direct people to exits | Needs careful acoustic design | Emergency priority and approval of the equipment for voice alarm use |
Voice does not replace visible notification for people with hearing loss, and people who cannot use the stairs need two-way communication at refuges, as our guide to fire telephones and areas of refuge explains.
Speech intelligibility: the real test
The most common site complaint is that the system is loud but nobody understands it. The usual cause is reverberation in hard-finished halls, glass atriums and concrete parking garages, and turning the volume up usually makes it worse.
NFPA 72 requires voice messages to be intelligible, meaning clear and understandable. The designer divides the building into acoustically distinguishable spaces and decides which need intelligible speech; some mechanical rooms may rely on tones. Intelligibility is commonly measured as STI: IEC 60268-16 (2020 edition) defines the method but no pass value for a building, so the target comes from the adopted standard and the specification.
What improves intelligibility
- More loudspeakers at lower power taps, rather than a few loud ones.
- Loudspeaker types and aiming matched to the space, such as column units in large halls.
- Early coordination with the architect on absorbent finishes in atriums and halls.
- Short, calm messages in Arabic followed by English, reviewed with building management and the consultant.
Survivability, secondary power and cables
A voice system that fails early cannot manage a phased evacuation, so NFPA 72 2025 requires pathway survivability where a voice system uses partial evacuation or relocation: Level 2 or 3 (2-hour rated cables or enclosures, Level 3 adding full sprinkler protection) in two-hour construction, or Level 4 (1-hour rated) in one-hour construction. Redundant Class N or X pathways at Level 1 are an allowed alternative, and the required route where construction is rated below one hour. A general alarm may use any level, and the 2025 edition applies the same rules to tones used for partial evacuation.
For secondary power, NFPA 72 requires 24 hours under quiescent load followed by 15 minutes at maximum connected load, and adding a safety margin, commonly 20% for battery aging, is good practice. Cable choice follows the survivability level, as our guide to fire alarm cables and circuit integrity explains.
Designing and installing a voice evacuation system: step by step
- Confirm the requirement and the reference standard (NFPA 72, or EN 54 with BS 5839-8) with the consultant.
- Zone the loudspeakers to match fire zones and the phased evacuation plan.
- Write alert, evacuate and all-clear messages and review them with the owner.
- Complete the acoustic design, amplifier loads and battery calculation from manufacturer data.
- Specify cables and survivability, and prepare the cause and effect matrix for the fire alarm interface.
- Submit drawings and calculations for approval, then install and program.
- Test every zone, measure intelligibility and train staff on the fire microphone.
Common site mistakes
- A few high-power loudspeakers filling a hall with echo instead of clear speech.
- English-only messages in a building where most visitors speak Arabic, or the reverse.
- Background music that keeps playing during an alarm because priority was never programmed.
- Loudspeaker zones that do not match fire zones, sending the evacuate message to the wrong area.
- Batteries never recalculated after loudspeakers were added during fit-out.
Inspection, testing, maintenance and cost
Chapter 14 of NFPA 72, or the adopted British standard, sets inspection and testing, with frequencies set by the adopted edition and Civil Defense. Under the 2025 edition, testers need not evaluate an existing approved design, and building changes that affect performance should be reported to the owner, so re-check intelligibility after renovations. Each visit should confirm that:
- Messages are understandable in every zone, not merely audible.
- The fire microphone works and overrides every other audio source.
- Loudspeaker circuit faults, open or short, are reported at the controller.
- Amplifiers, batteries and chargers are healthy, and no loudspeaker has been covered or moved.
What drives the cost?
There is no typical price to quote. The drivers are the number of zones and loudspeakers, amplifier redundancy, the reference standard and approvals, cable type and survivability level, difficult acoustics, paging integration, message languages, and intelligibility testing at handover.
How AZEIDK helps
AZEIDK’s fire alarm system solutions cover technical supply, installation, programming and testing, including integration with evacuation systems where required, supported by engineering design and calculations, loudspeaker zoning and Civil Defense approval support. Because AZEIDK also provides low-current systems, including public address systems, daily paging and the emergency function can be coordinated as one scope.
AZEIDK also supplies the Context Plus fire alarm range, including control panels and audible/visual sounders, with a compliance review for each project, plus Fire World fire alarm cables. After handover, annual maintenance contracts keep zones, messages and batteries tested, backed by more than 16 years in the Saudi market and 17+ branches and service regions.
FAQ
What is the difference between voice evacuation and a fire alarm bell?
A bell or sounder only warns that something is wrong. A voice evacuation system tells people what has happened, where to go and what to avoid, such as the elevators. That reduces hesitation, supports phased evacuation with different messages per zone, and lets building management or Civil Defense crews speak live.
Is voice evacuation mandatory in malls and hotels in Saudi Arabia?
It depends on occupancy, height, area and occupant load under the adopted edition of SBC 801 and SBC 201, Civil Defense requirements and the consultant’s specification. Large malls, hotels, towers and hospitals commonly have one. In the I-Codes model behind the Saudi code, high-rise buildings, malls over 50,000 sq ft (4,650 m²) and assemblies of 1,000 or more occupants require it.
Can the public address system be used for evacuation?
Yes, if it is designed and approved for the voice alarm function. Evacuation messages should override music and paging automatically, loudspeaker circuits should be monitored, and the system needs secondary power sized for alarm operation. An ordinary commercial sound system does not become a voice alarm system just by connecting it to the fire panel.
What is phased evacuation?
Phased evacuation empties a building in stages rather than all at once. The fire zone and the zones next to it evacuate first, while other zones hear an alert message to stand by. Towers and hospitals use it to avoid crowded stairs. It depends on accurate loudspeaker zoning, and NFPA 72 requires pathway survivability for it.
How do I know the messages are actually understood?
Listen and measure during commissioning. Intelligibility is commonly measured with speech transmission index methods from IEC 60268-16 in the spaces the design identifies, and the target value comes from the adopted standard and the consultant’s specification. Re-measure after any renovation that changes finishes, ceilings or room layouts.
Need a voice evacuation system people will understand? Send your drawings and we will review zoning, survivability and intelligibility for your project. Contact the AZEIDK team
