Cal. Rev. & Tax. Code § 214.11

For purposes of Section 214, property owned and operated by a nonprofit organization, otherwise qualifying for exemption under Section 214, shall be deemed to be exclusively used for hospital purposes so long as the property is exclusively used to meet the needs of hospitals which qualify for exemption from property taxation under Section 214 or any other law of the United States or this state. As used in this section, “needs of hospitals” includes any use incidental to, and reasonably necessary for, the functioning of a full hospital operation.