The department of human services shall visit and inspect each group child care home and group child care center as frequently as it deems necessary for the proper operation, sanitation, and safety of the home or center, as the case may be. The visits and inspections shall be made at least once annually. Every group child care home and group child care center licensed under this subpart shall be open to visitation and inspection by representatives of the department of human services, the department of education, and the department of health, and by designated representatives of the respective county fire departments at all times.