In a nursery school that holds a certificate of approval to operate, or a letter of exemption from approval, that was issued by the State Board of Education before December 1, 1971, and is still in effect, a minimum of 30 square feet of floor space shall be provided for each child. In a nursery school or child care program granted a letter of compliance after December 1, 1971, a minimum of 35 square feet of floor space shall be provided for each child. The office may not approve a capacity increase for a child care program or a nursery school currently approved, and wishing to maintain approval, to operate with less than 35 square feet per child. In calculating the square footage of floor space provided for each child, the following may not be included: Any floor space, rooms, or areas that are not suitable or available for the daily program activities of the children, such as but not limited to columns, vestibules, and corridors, food preparation areas, kitchens, bathrooms, adult work areas, permanently equipped isolation areas or sleeping rooms, storage units, and storage space; and Furniture, except for: Children's chairs and tables which are nonfixed and multipurpose; An adult-size rocking chair or other adult-size comfortable chair; Moveable play equipment; An adult-size couch; and Open shelves for children's daily activities.