Cal. HSC § 113953.1

(a) A handwashing facility shall be clean, unobstructed, and accessible at all times for employee use. (b) A handwashing facility shall not be used for purposes other than handwashing. (c) Employees shall not clean their hands in a sink used for food preparation, warewashing, or in a service sink or a curbed cleaning facility used for the disposal of mop water and similar liquid waste. (d) Notwithstanding subdivision (c), a warewashing sink may be used for handwashing as specified in Section 114125.