[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: 46CFR179.220]

[Page 243-246]
 
                           TITLE 46--SHIPPING
 
   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)
 
PART 179_SUBDIVISION, DAMAGE STABILITY, AND WATERTIGHT INTEGRITY--Table 
of Contents
 
         Subpart B_Subdivision and Damage Stability Requirements
 
Sec. 179.220  Location of watertight bulkheads for subdivision.

    (a) The maximum distance between adjacent main transverse watertight 
bulkheads on a vessel, required by Sec. 179.212(a) of this part to 
comply with this section, must not be more than the smaller of the 
following:
    (1) One third of the length of the bulkhead deck; or
    (2) The distance given by the following equation:
    [GRAPHIC] [TIFF OMITTED] TR10JA96.009
    
where:

d=the maximum length of the bulkhead deck in meters (feet) between 
adjacent main transverse watertight bulkheads;
F=the floodable length factor from Table 179.220(a);
f=the effective freeboard in meters (feet) calculated for each pair of 
adjacent bulkheads in accordance with paragraph (b) of this section;
L=Length Over Deck in meters (feet) measured over the bulkhead deck; and
D=the depth in meters (feet), measured amidships at a point one-quarter 
of the maximum beam out from the centerline, from the inside of the 
bottom planking or plating to the level of the top of the bulkhead deck 
at side as shown in Figure 179.220(a).

           Table 179.220(a)--Table of Floodable Length Factors
------------------------------------------------------------------------
            (d/L) x 100                               F
------------------------------------------------------------------------
                    0-15                                 0.33
                      20                                 0.34
                      25                                 0.36
                      30                                 0.38
                      35                                 0.43
                      40                                 0.48
                      45                                 0.54
                      50                                 0.61
                      55                                 0.63
                      60                                 0.58
                      65                                 0.53
                      70                                 0.48
                      75                                 0.44
                      80                                 0.40
                      85                                 0.37
                  90-100                                 0.34
------------------------------------------------------------------------
Note 1: Where: d=distance in meters (feet) from the midpoint of the
  compartment to the forward-most point on the bulkhead deck excluding
  sheer; and L=length over deck in meters (feet) measured over the
  bulkhead deck.
Note 2: Intermediate values of floodable length factor may be obtained
  by interpolation.


[[Page 244]]

[GRAPHIC] [TIFF OMITTED] TC01MR91.037

    (b) The effective freeboard for each compartment is calculated by 
the following equation:

f=(a+b)/2

where:

f=the effective freeboard in meters (feet).
a=the freeboard in meters (feet) measured:
    (1) At the forward main transverse watertight bulkhead; and
    (2) From the deepest waterline to:
(i) The top of the bulkhead deck on a flush deck vessel; or
(ii) If a vessel has a stepped bulkhead deck, the line shown in Figure 
179.220(b); or
(iii) If a vessel has an opening port light below the bulkhead deck, the 
line shown in Figure 179.220(c).
b=the freeboard in meters (feet) measured:
    (1) At the aft main transverse watertight bulkhead; and
    (2) From the deepest waterline to:

[[Page 245]]

(i) The top of the bulkhead deck on a flush deck vessel; or
(ii) If a vessel has a stepped bulkhead deck, the line shown in Figure 1 
to Sec. 179.220(b); or
[GRAPHIC] [TIFF OMITTED] TC01MR91.038


[[Page 246]]


[GRAPHIC] [TIFF OMITTED] TC01MR91.039

(iii) if a vessel has an opening port light below the bulkhead deck, the 
line shown in Figure 2 to Sec. 179.220(b).

[CGD 85-080, 61 FR 971, Jan. 10, 1996; 61 FR 20557, May 7, 1996]