Technical Booklet E Fire Safety·Page 171·6.21A, 6.21B
Evacuation alert systems for high-rise flats
Buildings with flats where the top storey exceeds 11 m must provide an evacuation alert system complying with BS 8629 that allows fire and rescue service to selectively initiate sounders in individual dwellings, floors, or the entire building.
In a building containing flats with a top storey more than 11 m above ground level, an evacuation alert system (EAS) should be provided in accordance with BS 8629.
The system should enable the fire and rescue service to initiate operation of evacuation alert sounders within each individual dwelling on any single floor, multiple floors and the entire building, according to circumstances.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/regional/Technical Booklet E - Fire Safety.pdf