A separating element for a platform cabin is provided. The separating element comprises: at least one stationary partition, delimiting a passage defining a circulation axis inside the cabin; at least one leaf, mounted transversely movable relative to the circulation axis between a closed position, in which it extends through the passage, and an open position, in which it is positioned at least partially spaced away from the passage; and means for moving the or each leaf between the closed position and the open position thereof, the or each leaf being adapted to move along the plane transverse to the circulation axis.