Cal. Health and Safety Code § 1578

A provider may share space with another licensed health facility, community care facility, senior center, or other appropriate structure, upon the approval of the department, based upon a determination of all of the following: (a) The use of the shared space does not jeopardize the welfare of the participant or other clients. (b) The shared use does not exceed occupancy capacity established for fire safety. (c) The space used by the adult day health care center is not essential to meet the other program’s licensing requirements. (d) Each entity schedules services and activities at separate times. This subdivision shall not apply to space used for meals or for space used by another licensed adult day services program. For purposes of this section, “shared space” means the mutual use of exits and entrances, offices, hallways, bathrooms, treatment rooms, and dining rooms by an adult day health care center and another program.