| S.No. | Field / Checkpoint | Reference | Status |
|---|---|---|---|
| A. INSTALLATION | |||
| A1 | PA amplifier + speakers + paging mic + zone splitter installed Acceptance: Verified | Per drawing | OK NC NA |
| A2 | Speaker placement per zone (1 per 50 m² typical for offices) Acceptance: Per drawing | Per acoustic design | OK NC NA |
| A3 | Cable type + segregation from EMI sources Acceptance: Per code | Shielded twisted pair | OK NC NA |
| B. FUNCTIONAL TEST | |||
| B1 | Audio level — 75 dBA above ambient noise; intelligibility STI ≥ 0.5 Acceptance: Measured | ISO 7240-19 / NFPA 72 | OK NC NA |
| B2 | Zone-wise paging + all-call functions Acceptance: Tested | Per spec | OK NC NA |
| B3 | Auto-music / paging override (priority) Acceptance: Tested | Per spec | OK NC NA |
| B4 | Fire emergency message (pre-recorded) — auto-trigger Acceptance: Tested | On fire alarm signal | OK NC NA |
| C. INTEGRATION | |||
| C1 | Integration with FAS — auto evacuation message Acceptance: Tested | Per fire strategy | OK NC NA |
| C2 | BMS + AV system integration (if applicable) Acceptance: Tested | Per spec | OK NC NA |
The Public Address (PA) System is a life-safety system on most commercial / public buildings — not just an amenity for music or announcements. During fire emergencies, the PA must deliver clear evacuation instructions to every occupant; the test of this is Speech Transmission Index (STI ≥ 0.5) plus audio level 75 dBA above ambient.
Under NBC 2016 Part 4, the PA system in Group A / B / C / D occupancies (assembly / business / mercantile / residential) is a mandatory life-safety component. Voice evacuation systems are required in: - Buildings > 15 m height - Hospitals + nursing homes - Schools + colleges - Shopping malls + multiplexes - IT parks + commercial offices (typically > 1,000 occupants) - Hotels + motels with > 30 rooms
The Testing & Commissioning (T&C) report is the formal evidence that the system was installed per design + tested per code + handed over functional. Without a signed T&C report, the building cannot obtain Fire NOC or Occupation Certificate.
Three test categories:
Installation verification: - Amplifier + power amp ratings match design (typically 100V line system for large buildings) - Speakers per zone — 1 per 50 m² for offices, 1 per 30 m² for malls - Speaker types: ceiling-recessed for offices, horn for warehouses, wall-mount for staircases - Cable type: FRLS or fire-survival cable for emergency paths - Segregation from EMI sources (LV cables separated > 300 mm from HV / VFD cables) - Earthing of amplifier chassis - Battery backup (UPS / standby) for 30 minutes minimum
Functional tests: - Audio level: SPL meter at 1m from each speaker; verify 75 dBA above ambient - STI test: Speech Transmission Index ≥ 0.5 (good intelligibility) for emergency zones; ≥ 0.45 for background music zones - Zone-wise paging: each zone tested independently + all-call function - Priority override: emergency message overrides music + low-priority paging - Fire emergency message: pre-recorded evacuation message triggered automatically on FAS signal - Tone test: 1 kHz tone at -10, -6, 0 dB; THD < 1%
Integration tests: - FAS interface: fire alarm triggers PA evacuation message - BMS / building automation integration (if specified) - AV system integration in conference rooms / auditoriums - Visual indicators (strobes) sync with PA for hearing-impaired occupants per Accessibility code
1. STI not measured — many sites measure only SPL (loudness) but skip STI (intelligibility). A loud but unintelligible system fails the actual life-safety test.
2. Speaker layout wrong — uniform speaker spacing without considering room acoustics; dead zones in long corridors or echo zones in atriums.
3. No FAS integration test — PA tested in isolation; integration with FAS not actually triggered; on real fire, system silent.
4. Cable not FRLS — standard PVC cable used in life-safety paths; cable fails in 5 minutes of fire; PA silent when most needed.
5. No battery backup test — UPS shown on paper but not load-tested; battery dead at first power failure.
6. Zone splitter wrong — fire on Floor 3 plays evacuation on Floor 3 only; should be evacuation on Floor 3, 4 + 2 (3-floor evacuation protocol per NBC).
7. Background music too loud — masks emergency message audibility; volume calibration not done per zone.
8. Microphone feedback — paging mic placed near speakers; feedback at peak volume; emergency announcements unintelligible.
9. No periodic test schedule — T&C done at handover; no quarterly test plan; system degrades silently over 2-3 years.
10. Pre-recorded message in wrong language — multi-lingual zones not configured; non-English speakers can't follow instructions.
Companion formats: - FAS Testing & Commissioning (FMT-MEP-005) — fire alarm system (PA integration) - Wet Riser + Hydrant T&C (FMT-MEP-010) - BMS T&C — building automation integration - Emergency Lighting T&C — companion life-safety system
Standards: - NBC 2016 Part 4 — Fire and Life Safety (Voice Evacuation requirements) - IS 2189:2008 — Automatic Fire Detection and Alarm Systems Code - ISO 7240-16:2007 — Sound system control + indicating equipment - ISO 7240-19:2007 — Design, installation, commissioning + service of sound systems for emergency purposes - EN 54-16 / EN 54-24 — European voice alarm equipment standards (referenced in international projects) - IEC 60849 — Sound systems for emergency purposes (older but referenced) - NFPA 72 — National Fire Alarm + Signalling Code (US, referenced in tier-1 projects)