Visibility and Variety: Be certain that Visible alarms are sufficiently several and placed strategically to become visible from all areas. So as to avoid discrimination, BS EN 54-23 compliant VADs could be set up in all sanitary accommodation (not just WCs) and all hotel bedrooms, pupil accommodation and similar Attributes, https://www.firesense.co.uk/type/addressable-fire-system/addressable-sounders-vids-vads/