An owner shall post and maintain a sign, placard or plate in approved form, after making application so to do, showing safe loading for each floor, and safe capacity in persons at entrances of each room, floor, or building built or used for any of the following purposes: school; church; public assembly; residential institution; a place for harboring or housing persons for correctional, medical or other care or treatment; storing materials; dance or recreation hall, and serving of drinks or food. (Ord. 60-09, 5-12-1960)