For LOX, and LIN tanks, the external surface of the inner tank and piping and the inner surfaces of the outer tank shall be cleaned to meet Class SC acceptance criteria as defined by 4WPI-SW70001.3.11.5Any hot-formed parts or cold-formed and subsequently heated-treated parts in contact with LOX shall be pickled and passivated.For all other stainless steel cold- formed parts, unless otherwise specified, Air Products does not require suppliers to pickle and passivate.