Overview
ISO 7240-3:2020 - Fire detection and alarm systems - Part 3: Audible alarm devices specifies requirements, test methods and performance criteria for audible alarm devices (AADs) used to signal audible warnings, with or without voice messages, between a fire detection and fire alarm system and building occupants. The standard covers devices for two application environments: type A (indoor) and type B (outdoor). It is the ISO 2020 second edition and excludes loudspeaker systems primarily intended for external voice sources and supervisory audible devices within control equipment.
Key topics and technical requirements
The standard addresses both performance and durability aspects of AADs and defines testing and compliance procedures. Important technical topics include:
- Sound pressure level and frequency requirements to ensure audibility and intelligibility of warnings and voice messages.
- AADs with voice - requirements for devices that include on-board voice capability and timing/sequence tests for voice messages.
- Synchronization (optional) - methods for synchronizing multiple devices to avoid interference or confusing signals.
- Construction and materials - provisions for external conductors, material selection and access for maintenance.
- Ingress protection (IP) to classify suitability for indoor or outdoor environments (type A/type B).
- On-site adjustment - permitted adjustments for mode of operation.
- Durability and environmental tests - defining endurance and operational tests such as dry heat, cold, damp heat (cyclic and steady-state), SO2 corrosion, shock, impact, vibration, EMC immunity and enclosure protection.
- Test methods and reproducibility - detailed procedures, tolerances, mounting arrangements and reporting requirements to verify compliance.
Keywords: ISO 7240-3:2020, audible alarm devices, fire alarm, AADs, sound pressure level, ingress protection, EMC testing.
Practical applications
ISO 7240-3:2020 is applied to:
- Specifying and procuring compliant audible alarms for commercial, residential and industrial buildings.
- Designing fire alarm systems that require reliable audible warnings and voice evacuation messages.
- Developing product test plans and certification dossiers for AAD manufacturers.
- Field verification and commissioning of alarm devices to meet regulatory and insurance requirements.
Who should use this standard
- Fire safety engineers and system designers
- Alarm device manufacturers and R&D teams
- Test laboratories and certification bodies
- Installers, commissioning agents and facility managers
- Authorities having jurisdiction and code writers
Related standards
ISO 7240 is a multi‑part series. ISO 7240-3 should be used alongside other parts of the ISO 7240 series covering detectors, control and indicating equipment, and system requirements to ensure full fire detection and alarm system compliance.
