Overcrowding. No bedroom or room used as a bedroom in any class “b” multiple dwelling shall be so occupied as to provide less than 500 cubic feet of air space per occupant, exclusive of the cubic air space of bathrooms, toilet rooms and closets. No room, suite or group of rooms, comprising a family dwelling unit, in any single, 2 family or class “a” multiple dwelling shall be so occupied as to provide less than 800 cubic feet of air space per occupant exclusive of the cubic air space of bathrooms, toilet rooms and closets. No bedroom or room used as a bedroom in any single, 2 family or class “a” multiple dwelling shall be so occupied as to provide less than 300 cubic feet of air space per occupant, exclusive of the cubic air space of bathrooms, toilet rooms and closets.