ISO 7240-27:2018

Overview - ISO 7240-27:2018 (multi-sensor point fire detectors)

ISO 7240-27:2018 is an international standard for fire detection and alarm systems that defines requirements, test methods and performance criteria for multi-sensor point fire detectors that combine a smoke sensor with a carbon monoxide (CO) sensor and, optionally, one or more heat sensors. It applies to detectors intended for use in building fire detection and alarm systems (see ISO 7240‑1). The standard is intended for type testing and product evaluation and is not applicable to devices developed for highly specific risks or with special characteristics.

Key technical topics and requirements

This part of the ISO 7240 series covers both functional and environmental performance aspects, including:

• Response thresholds for smoke (optical scattered/transmitted light), CO and optional heat sensors
• Repeatability and reproducibility tests to ensure consistent smoke and CO response
• Directional dependence of sensor response and rate-sensitive CO behaviour
• Long-term stability and saturation tests for CO sensors
• Environmental and durability tests: dry heat, cold, air movement, chemical exposure at environmental concentrations, dazzling, and supply variation effects
• Software-controlled detector requirements, including software design and storage of programs/data
• Manufacturer and on-site adjustment provisions, monitoring of detachable detectors, and protection against ingress of foreign bodies
• Test methods and reporting, with specified atmospheric/operating conditions, mounting arrangements and tolerances

These topics reflect the standard’s emphasis on measurable performance, repeatable test procedures and clear criteria for acceptance.

Practical applications - who uses ISO 7240-27

ISO 7240-27 is used by a range of stakeholders in the fire safety ecosystem:

• Detector manufacturers - for design validation, type testing and product certification of multi-sensor point detectors (smoke + CO ± heat)
• Test laboratories - to perform standardized performance and environmental tests required for compliance and certification
• Fire safety engineers and system designers - to select appropriate detectors that meet specified response characteristics for building applications
• Installers, specifiers and authorities having jurisdiction (AHJs) - to verify that devices satisfy recognized performance criteria for building codes and fire alarm systems
• Facility owners and risk managers - to evaluate detector suitability for particular occupancies (offices, residential, retail, etc.)

Related standards

• ISO 7240‑1 (general requirements for fire detection and alarm systems) - referenced in the scope.
• Other parts of the ISO 7240 series cover different detector types and system components; ISO 7240-27 is specifically focused on point-type multi-sensor detectors combining smoke and CO sensing.

Keywords: ISO 7240-27, fire detection and alarm systems, multi-sensor point fire detectors, smoke sensor, carbon monoxide sensor, heat sensor, test methods, performance criteria, detector certification.