This document specifies minimum requirements for the planning, installation, operation and maintenance of smoke alarms according to DIN EN 14604 in residential buildings, apartments and rooms with housing-like use. This standard has been prepared by the working group NA 031-02-05 AA "Smoke alarms - SpA to CEN/TC72/WG 14" of the FNFW. The requirements for the installation of smoke alarms in corridors with underbeams were frequently requested for interpretation from the responsible working committee. This amendment is intended to reflect the results.