Section 173.056 - Collision and other watertight bulkheads(a) Collision bulkheads required by this section must comply with the requirements in § 171.085 of this subchapter.(b) Each sailing school vessel required to meet paragraph (a) of § 173.054 must comply with the machinery space bulkhead requirements in § 171.095 of this subchapter.CGD 83-005, 51 FR 924, Jan. 9, 1986