30 CFR 57.20002 - Potable water.
(a) An adequate supply of potable drinking water shall be provided at all active working areas.
(b) The common drinking cup and containers from which drinking water must be dipped or poured are prohibited.
(c) Where single service cups are supplied, a sanitary container for unused cups and a receptacle for used cups shall be provided.
(d) When water is cooled by ice, the ice shall either be of potable water or shall not come in contact with the water.
(e) Potable water outlets shall be posted.
(f) Potable water systems shall be constructed to prevent backflow or backsiphonage of non-potable water.