ISO 7240-22:2017

Overview - ISO 7240-22:2017 (Smoke-detection equipment for ducts)

ISO 7240-22:2017 is an international standard that specifies requirements, test methods and performance criteria for smoke-detection equipment for ducts (SDED) used in building fire detection and alarm systems. It covers devices that sample air from HVAC or other ductwork and detect smoke in that sampled air. The standard describes allowed detector types (e.g., scattered-light, transmitted-light and ionization principles), common methods of sampling (such as differential-pressure sampling from duct airflow), and guidance for testing detectors that are not explicitly covered by other parts of ISO 7240.

Keywords: ISO 7240-22:2017, smoke-detection equipment for ducts, SDED, duct smoke detectors, fire detection and alarm systems.

Key topics and technical requirements

ISO 7240-22:2017 addresses technical and procedural areas essential to reliable duct smoke detection:

• Scope & definitions: Clarifies which SDEDs are covered and which special-purpose detectors are excluded.
• Performance requirements: Criteria for detector response behavior and repeatability/reproducibility of detections.
• Test methods: Detailed test procedures including environmental and operational tests such as:
  • dry heat, cold, damp heat (operational and endurance)
  • vibration, shock and impact
  • air leakage and smoke sensitivity
  • sulfur dioxide corrosion endurance
  • electromagnetic compatibility (EMC) immunity
  • dazzling/light interference tests
• Software and documentation: Requirements for software-controlled equipment, program storage and hardware/software documentation.
• Marking and data: Information that must be supplied with products and test reports.
• Compatibility with detector types: SDED may incorporate detectors complying with ISO 7240‑7 or follow ISO 7240‑22 test provisions for other principles, including ionization detectors.

Practical applications

ISO 7240-22 is used to ensure reliable early detection of smoke within building ductwork and HVAC systems. Typical applications:

• Early smoke detection in air-handling units and duct systems to prevent smoke spread.
• Protection of server rooms, cleanrooms, shopping centers, atria and corridors served by mechanical ventilation.
• Integration of duct detectors into building fire alarm strategies and smoke control systems.

Keywords: duct smoke detectors, HVAC smoke detection, air-handling unit safety.

Who should use this standard

• Manufacturers of duct smoke detectors and sampling equipment
• Test laboratories performing type and endurance tests
• Fire alarm system designers and installers specifying SDED for buildings
• Regulatory authorities and specifiers developing building safety and fire protection requirements

Related standards

• ISO 7240-1 (general requirements for fire detection and alarm systems)
• ISO 7240-7 (point-type smoke detectors) - referenced for compatible detector modules

This standard is essential for stakeholders seeking validated, tested duct smoke-detection solutions compliant with international test and performance criteria.