Various embodiments include a fire or smoke alarm comprising: a detection arrangement arranged within an alarm housing; and an alarm-housing cover having, on an inner side, a plurality of housing ribs pointing radially in the direction of an alarm dome. The detection arrangement comprises a level divider with an opening. A maximum possible spacing between two points on a peripheral line of the opening or on a common peripheral line of a plurality of openings is larger than a diameter of the alarm dome. The peripheral line of the opening or the common peripheral line of a plurality of openings in the level divider extends beyond the alarm dome of the alarm-housing cover on all sides.