Design Specifications for Hotel Background Music and Emergency Broadcast Systems

Design Specifications for Hotel Background Music and Emergency Broadcast Systems

I am David Zhou, a low-voltage/intelligent systems expert. Your question on the design specifications for hotel background music and emergency broadcast systems concerns a core aspect of hotel intelligent systems that involves both safety and guest experience. In accordance with GB 50116-2013 Code for Design of Automatic Fire Alarm Systems, GB 50526-2010 Technical Code for Public Address System Engineering, and hotel industry standards, the system must simultaneously satisfy daily background music broadcasting and mandatory evacuation broadcasting in emergencies such as fire. The following analysis combines code clauses with engineering experience.

1. System Architecture and Functional Integration

• Code requirements: Clause 3.1.2 of GB 50526-2010 states that the public address system shall have emergency broadcast priority and automatically switch to emergency mode in the event of fire or an emergency. Hotel background music systems typically share loudspeakers, amplifiers and wiring with the emergency broadcast system, but must achieve differentiated functions through zone control.
• Design points:
• Zoning: According to Clause 6.1.3 of GB 50116-2013, broadcast zones must be consistent with fire alarm zones. For example, guest room areas, the lobby, restaurants, corridors and underground garages should be independent zones to facilitate targeted broadcasting by floor or area during a fire.
• Priority logic: Emergency broadcast must forcibly override background music and have the highest priority. Switching is typically triggered by dry contact signals from the fire linkage controller (e.g., brands such as GST, Honeywell).
• Power reserve: Clause 5.2.3 of GB 50526-2010 requires that the rated amplifier power be 1.3–1.5 times the total loudspeaker power to ensure adequate sound pressure level during emergency broadcast.
• Engineering case: In the design of a five-star hotel, ceiling loudspeakers (6W/8Ω) were used in the lobby without considering fire zoning (the lobby and corridor shared one zone), so the lobby occupants could not be evacuated separately during the fire test. After rectification, wiring was redone with one zone per 500㎡ and independent amplifier modules were added, and the system finally passed acceptance.

2. Loudspeaker Selection and Layout

• Code requirements: Clause 6.1.5 of GB 50116-2013 explicitly stipulates that emergency broadcast loudspeakers shall be installed in corridors, halls and other densely occupied places, and their number shall ensure that the walking distance from any point in a fire compartment to the nearest loudspeaker is no more than 25m, and that the loudspeaker at the end of a corridor is no more than 12.5m from the wall.
• Design points:
• Sound pressure level: For background music, loudspeaker rated power is typically 3W–6W (e.g., brands such as JBL, BOSE); for emergency broadcast, it must be switched via the amplifier to 15W–30W to ensure a sound pressure level ≥75dB (Clause 4.2.1 of GB 50526-2010).
• Waterproof and dustproof: Areas such as outdoor pools and gardens require IP65-rated waterproof loudspeakers (e.g., TOA, Bowei).
• Aesthetics: For high-end areas such as the hotel lobby and banquet hall, decorative loudspeakers must be customised (e.g., recessed into the ceiling or integrated with light fixtures) to avoid disrupting the interior design style.
• Engineering case: A resort hotel used ordinary ceiling loudspeakers in the pool area, and moisture during the rainy season caused short circuits. They were subsequently replaced with IP65-rated wall-mounted loudspeakers (e.g., DSPPA brand) and waterproof junction boxes were added, reducing the failure rate to zero.

3. Emergency Broadcast Linkage and Power Supply Assurance

• Code requirements: Clause 6.1.1 of GB 50116-2013 requires that the emergency broadcast system be linked with the fire alarm system and triggered automatically or manually. Meanwhile, Clause 5.4.1 of GB 50526-2010 emphasises that the system shall be equipped with dual power supplies (mains primary + battery backup), with the backup power supply capable of continuous supply for ≥30 minutes.
• Design points:
• Linkage logic: The fire alarm controller (e.g., Siemens FC series) outputs a signal to the broadcast host, which plays pre-recorded voice messages according to a preset program (e.g., evacuating the fire floor and the floors above and below first).
• Backup power: Battery capacity must support all emergency broadcast amplifiers operating simultaneously for 30 minutes; lead-acid battery banks are recommended (e.g., brands such as Panasonic, Yuasa), with capacity ≥100Ah (calculated according to total power).
• Manual control: Manual switch buttons must be provided in the fire control room for emergency operation by duty personnel.
• Engineering case: A hotel was judged non-compliant during fire acceptance because its backup power supply supported only 10 minutes. The battery bank was subsequently upgraded to 120Ah and UPS (uninterruptible power supply) redundancy was added, meeting the code requirements.

4. Key Points of Construction and Acceptance

• Code requirements: Chapter 19 of GB 50303-2015 Code for Acceptance of Construction Quality of Building Electrical Engineering contains detailed provisions on broadcast system construction, such as firestop sealing for conduit laying and grounding resistance ≤4Ω.
• Engineering experience:
• Cable selection: RVV 2×1.5mm² may be used for background music cables; emergency broadcast requires flame-retardant cable (ZR-RVS 2×1.5mm²) to prevent the cable from feeding a fire.
• Commissioning and testing: Acceptance requires sound pressure level measurement (e.g., using a sound level meter), zone switching tests and linkage delay tests (should be ≤3 seconds).
• Case: A hotel was ordered to rectify because it did not use flame-retardant cables during the fire inspection, and passed after replacement.

Summary

The above are reference opinions. The actual project situation still needs to be comprehensively evaluated and implemented in combination with specific operating conditions, site conditions and other factors.