ISO 12239:2010 specifies requirements, test methods, performance criteria, and manufacturer's instructions for smoke alarms that operate using scattered light, transmitted light, or ionization, and are intended for household or similar residential applications. For the testing of other types of smoke alarms, or smoke alarms working on different principles, ISO 12239:2010 should be used only for guidance. Smoke alarms with special characteristics and developed for specific risks are not covered by ISO 12239:2010.