CFR > Title 46 - Shipping > CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY > SUBCHAPTER S—SUBDIVISION AND STABILITY (parts 170 to 174) > PART 171—SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS > SUBPART C—Large Vessels (§171.045 to §171.082) > 171.068—Special considerations for Type I subdivision for vessels on short international voyages.

171.068—Special considerations for Type I subdivision for vessels on short international voyages.

(a) The calculations done to demonstrate compliance with § 171.065 for a vessel that makes short international voyages and is permitted under § 75.10-10 of this chapter to carry a number of persons on board in excess of the lifeboat capacity must—
(1) Assume the uniform average permeabilities given in Table 171.068 in lieu of those in Table 171.066; and
(2) Use a factor of subdivision (FS) that is the smaller of the following:
(i) The value from Table 171.065(a).
(ii) 0.50.
(b) For a vessel less than 300 feet (91 meters) in length, the Commanding Officer, Marine Safety Center may approve the separation of main transverse watertight bulkheads greater than that permitted by paragraph (a) of this section if—
(1) The shorter separation is impracticable; and
(2) The separation is the smallest that is practicable.
(c) In the case of ships less than 180 feet (55 meters) in length, the Commanding Officer, Marine Safety Center may approve a further relaxation in the bulkhead spacing. However, in no case may the separation be large enough to prevent the vessel from complying with the flooding requirements for Type II subdivision in § 171.070.
Table 171.068—Table of Uniform Average Permeabilities
Location Uniform average permeability
10 (a−c)
Machinery Space 85 ____
v
35(b)
Volume Forward of Machinery Space 95−__
v
35(b)
Volume Aft of Machinery Space 95−___
v
For each location specified in this table—
a=volume below the margin line of all spaces that, in the full load condition, normally contain no cargo, baggage, stores, provisions, or mail.
b=volume below the margin line and above the tops of floors, inner bottoms, or peak tanks of coal or oil fuel bunkers, chain lockers, fresh water tanks, and of all spaces that, in the full load condition, normally contain stores, baggage, mail, cargo, or provisions. If cargo holds are not occupied by cargo, no part of the cargo space is to be included in this volume.
c=volume below the margin line of the cargo, stores, provisions, or mail spaces within the limits of the machinery space.
v=total volume below the margin line.
[CGD 79-023, 48 FR 51017, Nov. 4, 1983, as amended by CGD 88-070, 53 FR 34537, Sept. 7, 1988]