The AHS defines a housing unit as a house, apartment, group of rooms, or single room occupied or intended for occupancy as separate living quarters. Group quarters (institutional or noninstitutional) are not classified as housing units and are not covered by AHS interviews. Other types of living quarters, such as rooming houses or hotels are sometimes classified as housing units if certain conditions are met, such as being occupied by fewer than 8 people, being separate living quarters (occupants live separately from any other people in the structure), having direct access from the outside of the structure or through a common area (hall, lobby, or vestibule intended for use by the general public), and being occupied by permanent residents. For more information, see the “Housing units” entry in the AHS Subject Definitions.