(a) Except as prescribed in paragraphs (b) and (c) of this section, containment systems carrying sulfuric acid, oleum, or contaminated sulfuric acid are approved by the Commandant (CG-ENG) on a case by case basis.
(b) A containment system carrying sulfuric acid may be:
(1) Made of unlined steel if the cargo composition is between 70 and 80 or between 90 and 100 percent acid by weight;
(2) Lined with lead if the cargo composition does not exceed 96 percent acid by weight; or
(3) Lined with natural rubber or neoprene if the cargo composition does not exceed 51 percent acid by weight.
(c) A containment system for oleum may be of unlined steel if the concentration of free sulfur trioxide in the oleum exceeds 20 percent by weight.