ISO 7240-7:2023

Overview - ISO 7240-7:2023 (Point‑type smoke detectors)

ISO 7240-7:2023 is the fourth edition standard for point-type smoke detectors using scattered light, transmitted light or ionization. It specifies requirements, test methods and performance criteria for these detectors when used in building fire detection and alarm systems (see ISO 7240-1 for general system requirements). The standard also addresses multi‑sensor point detectors that combine two or more of the listed detection principles (additional requirements in Annex N). ISO 7240-7:2023 is intended for conventional building applications and is not applicable to detectors with special characteristics developed for specific risks. Note: some ionization detectors contain radioactive materials.

Key technical topics and requirements

• Scope & conformance: Defines applicability, relationship to ISO 7240-1 and the limits of use (guidance only for other detector types).
• Response thresholds: Measurement and specification of detector response for scattered‑light and transmitted‑light types.
• Individual alarm indication & ancillary connections: Requirements for alarm signalling, monitoring detachable detectors and connecting ancillary devices.
• Software requirements: Design, control and storage requirements for software‑controlled detectors.
• Environmental and mechanical tests: Operational and endurance tests including dry heat, cold, damp heat, SO2 corrosion, shock, impact, vibration and EMC immunity.
• Functional performance tests: Repeatability, reproducibility, directional dependence, supply variation, air movement effects, dazzling and fire sensitivity.
• Open vs closed detectors: Additional tests and ingress‑protection considerations for open‑type designs.
• Test procedures & reporting: Detailed test arrangements, atmospheric/operating conditions, tolerances and required test reports.

Practical applications - who uses ISO 7240-7

• Manufacturers: product design, type testing, product verification and CE/market compliance for point‑type smoke detectors.
• Test laboratories and certification bodies: apply standardized test methods and performance criteria for certification and type approval.
• Fire safety engineers & consultants: select appropriate detector technologies, assess performance under environmental conditions and specify detectors in building projects.
• Installers & system integrators: ensure correct detector selection, mounting and commissioning consistent with performance requirements.
• Building owners / procurement teams: evaluate product claims and ensure purchased detectors meet standardized performance and safety criteria.

Related standards

• ISO 7240-1 - general requirements for fire detection and alarm systems (referenced by ISO 7240-7).
• Other parts of the ISO 7240 series cover different detector types and system components.

Keywords: ISO 7240-7, point-type smoke detectors, scattered light, transmitted light, ionization, fire detection and alarm systems, smoke detector testing, performance criteria, EMC immunity.