[Code of Federal Regulations] [Title 46, Volume 7] [Revised as of October 1, 2004] From the U.S. Government Printing Office via GPO Access [CITE: 46CFR171.065] [Page 124-126] TITLE 46--SHIPPING CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PART 171_SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS--Table of Contents Subpart C_Large Vessels Sec. 171.065 Subdivision requirements-- Type I. (a) Except as provided in paragraphs (c) and (f) of this section, the separation between main transverse watertight bulkheads on a vessel, other than one described in paragraph (b) of this section, must not exceed-- (floodable length)x(factor of subdivision) where-- the factor of subdivision is listed under FS in Table 171.065(a). (b) The factor of subdivision used to determine compliance with paragraph (a) of this section must be the smaller of 0.5 or the value determined from Table 171.065(a) if-- (1) The vessel is 430 feet (131 meters) or more in LBP; and (2) The greater of the values of Y as determined by the following equations equals or exceeds the value of X in Table 171.065(b): [GRAPHIC] [TIFF OMITTED] TC01MR91.018 or [GRAPHIC] [TIFF OMITTED] TC01MR91.019 where-- M, V, and P have the same value as listed in Table 171.065(a); and P1=the smaller of the following: (i) 0.6LN (0.056LN) where-- N=the total number of passengers; and L=LBP in feet (meters). (ii) The greater of the following: (A) 0.4LN (0.037LN). (B) The sum of P and the total volume of passenger spaces above the margin line. (c) The distance A in Figure 171.065 between main transverse watertight bulkheads may exceed the maximum allowed by paragraphs (a) or (b) of this section if each of the distances B and C between adjacent main transverse watertight bulkheads in Figure 171.065 does not exceed the smaller of the following: (1) The floodable length. (2) Twice the separation allowed by paragraphs (a) or (b) of this section. (d) In each vessel 330 feet (100 meters) or more in LBP, one of the main transverse watertight bulkheads aft of the collision bulkhead must be located at a distance from the forward perpendicular that is not greater than the maximum separation allowed by paragraph (a) or (b) of this section. (e) The minimum separation between two adjacent main transverse watertight bulkheads must be at least 10 feet (3.05 meters) plus 3 percent of the LBP of the vessel, or 35 feet (10.7 meters), whichever is less. (f) The maximum separation of bulkheads allowed by paragraphs (a) or (b) of this section may be increased by the amount allowed in paragraph (g) of this section if-- (1) The space between two adjacent main transverse watertight bulkheads contains internal watertight volume; and [[Page 125]] (2) After the assumed side damage specified in paragraph (h) of this section is applied, the internal watertight volume will not be flooded. (g) For the purpose of paragraph (f) of this section, the allowable increase in separation is as follows: [GRAPHIC] [TIFF OMITTED] TC01MR91.020 where-- ``total volume of allowed local subdivision'' is determined by calculating the unflooded volume on each side of the centerline and multiplying the smaller volume by two. (h) The assumed extents of side damage are as follows: (1) The longitudinal extent of damage must be assumed to extend over a length equal to the minimum spacing of bulkheads specified in paragraph (e) of this section. (2) The transverse extent of damage must be assumed to penetrate a distance from the shell plating equal to one-fifth the maximum beam of the vessel and at right angles to the centerline at the level of the deepest subdivision load line. (3) The vertical extent of damage must be assumed to extend vertically from the baseline to the margin line. (i) The maximum separation between the following bulkheads must not exceed the maximum separation between main transverse watertight bulkheads: (1) The collision bulkhead and the first main transverse watertight bulkhead aft of the collision bulkhead; and (2) The last main transverse watertight bulkhead and the aftermost point on the bulkhead deck. (j) The minimum separation between the following bulkheads must not be less than the minimum separation between main transverse watertight bulkheads: (1) The collision bulkhead and the first main transverse watertight bulkhead aft of the collision bulkhead; and (2) The last main transverse watertight bulkhead and the aftermost point on the bulkhead deck. [GRAPHIC] [TIFF OMITTED] TC01MR91.021 Table 171.065(a) (English units) ------------------------------------------------------------------------ Vessel length (LBP) Criterion numeral (CN) FS ------------------------------------------------------------------------ CN less than or equal A to 23. Vessel length greater than 392 feet CN greater than 23 and F1 less than 123. CN greater than or B equal to 123. ------------------------------------ CN less than or equal 1 to S. Vessel length greater than or equal CN greater than S and F2 to 200 feet and less than or equal less than 123. to 392 feet. CN greater than or B equal to 123. ------------------------------------ Vessel length less than 200 feet... ...................... 1 ------------------------------------------------------------------------ Where-- FS=the factor of subdivision. CN=60((M+2P)/V)+30000(N/L\2\) A=(190/(L-160))+0.18 B=(94/(L-85))+0.18 F1=A-((A-B)(CN-23)/100) S=(10904-25L)/48 F2=1-((1-B)(CN-S)/(123-S)) L=the length of the vessel (LBP) in feet. M=the sum of the volume of the machinery space and the volumes of any fuel tanks which are located above the inner bottom forward or aft of the machinery space in cubic feet. P=the volume of passenger spaces below the margin line. V=the volume of the vessel below the margin line. N=the number of passengers that the vessel is to be certificated to carry. [[Page 126]] Table 171.065(a) (Metric Units) ------------------------------------------------------------------------ Vessel length (LBP) Criterion numeral (CN) FS ------------------------------------------------------------------------ CN lesthan or equal to A 23. Vessel length greater than 120 CN greater than 23 and F1 meters. less than 123. CN greater than or B equal to 123. ------------------------------------ CN less than or equal 1 to S. Vessel length greater than or equal CN greater than S and F2 to 61 meters and less than or less than 123. equal to 120 meters. CN greater than or B equal to 123. ------------------------------------ Vessel length less than 61 meters.. ...................... 1 ------------------------------------------------------------------------ Where-- FS=the factor of subdivision. CN=60((M+2P)/V)+2787(N/L\2\) A=(58/(L-49))+0.18 B=(29/(L-26))+0.18 F1=A-((A-B)(CN-23)/100) S=(3323.5-25L)/14.6 F2=1-((1-B)(CN-S)/(123-S)) L=the length of the vessel (LBP) in meters. M=the sum of the volume of the machinery space and the volumes of any fuel tanks which are located above the inner bottom forward or aft of the machinery space in cubic meters. P=the volume of passenger spaces below the margin line. V=the volume of the vessel below the margin line. N=the number of passengers that the vessel is to be certificated to carry. Table 171.065(b)--Table of X ------------------------------------------------------------------------ Vessel LBP in feet (meters) X \1\ ------------------------------------------------------------------------ 430 (131)...................................................... 1.336 440 (134)...................................................... 1.285 450 (137)...................................................... 1.230 460 (140)...................................................... 1.174 470 (143)...................................................... 1.117 480 (146)...................................................... 1.060 490 (149)...................................................... 1.002 500 (152)...................................................... 0.944 510 (155)...................................................... 0.885 520 (158)...................................................... 0.826 530 (162)...................................................... 0.766 540 (165)...................................................... 0.706 550 (168)...................................................... 0.645 554 (169) and up............................................... 0.625 ------------------------------------------------------------------------ 1 Interpolate for intermediate values.