Wash. Admin. Code § 246-203-210
No person, firm, corporation or authorities owning, in charge of, or in control of any hotel, theatre, restaurant, lodging house, factory, school, church, store, office building, railway, trolley or other public conveyance station, or public conveyance by land, water or air, or other institution or conveyance frequented by the public or which may be used for the purpose of public assembly or as a place of employment, is permitted to furnish any cup, vessel or other receptacle for common use in any such place for drinking or eating purposes.
The term "common use" in this section shall be construed to mean, for use by more than one person without adequate cleansing.
Wash. Admin. Code § 246-203-210
Statutory Authority: RCW 43.20.050. 91-02-051 (Order 124B), recodified as § 246-203-210, filed 12/27/90, effective 1/31/91; Regulation .50.210, effective 3/11/60.