Where systems installed on vessels for wash water, as defined in Sec. 1250.3(n), do not comply with the requirements of a potable water system, prescribed in Sec. 1250.82, they shall be constructed so as to minimize the possibility of the water therein being contaminated. The storage tanks shall comply with the requirements of Sec. 1250.83, and the distribution system shall not be cross connected to a system carrying water of a lower sanitary quality. All faucets shall be labeled ``Unfit for drinking''.