ISO 7240-22:2007

ISO 7240-22:2007 specifies requirements, test methods and performance criteria for smoke detection equipment for ducts (s.d.e.d.) for use in fire-detection and fire alarm systems installed in buildings.
The s.d.e.d. samples the air from a duct and detects smoke in the sample. A common method of operation is to use differential pressure arising from airflow in the duct.
The s.d.e.d. can use smoke detectors complying with ISO 7240-7 or other detectors complying with tests specified in ISO 7240-22:2007.
A common application for s.d.e.d. is to detect visible smoke, for which detectors using scattered light or transmitted light can be more suitable. However, requirements for detectors using ionization are also included in ISO 7240-22:2007 for use in applications where detection of less visible fire aerosols is desired.
For the testing of other types of smoke detectors or smoke detectors working on different principles, ISO 7240-22:2007 can be used for guidance. Smoke detectors with special characteristics, developed for specific risks, are not covered.