[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: 46CFR171.015]

[Page 114-116]
 
                           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 A_General
 
Sec. 171.015  Location of margin line.

    (a) A vessel with a continuous bulkhead deck and sufficient sheer. 
If the average value of the sheer at the forward perpendicular (FP) and 
the after perpendicular (AP) is at least 12 inches (30.5 cm), the margin 
line must be located no less than 3 inches (7.6 cm) below the upper 
surface of the bulkhead deck at side as illustrated in Figure 
171.015(a).

                              Table 171.015
------------------------------------------------------------------------
                                                  Required position of
 Average value of sheer at FP and AP in inches  margin line below top of
                     (cm)                       deck amidships in inches
                                                          (cm)
------------------------------------------------------------------------
12 (30.5).....................................            3 (7.6)
6 (15.2)......................................           6 (15.2)
0.............................................           9 (22.8)
------------------------------------------------------------------------

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    (b) A vessel with a continuous bulkhead deck and insufficient sheer. 
If the average value of the sheer at the forward perpendicular (FP) and 
the after perpendicular (AP) is less than 12 inches (30.5 cm), the 
margin line must be a parabolic curve with the following 
characteristics:
    (1) The parabolic curve must be at least 3 inches (7.6 cm) below the 
upper surface of the bulkhead deck at the FP and AP.
    (2) The parabolic curve must be at least the distance given in Table 
171.015 below the surface of the bulkhead deck amidships.
    (3) Intermediate values not shown in Table 171.015 must be 
interpolated.
    (4) Figure 171.015(b) illustrates a margin line drawn in this 
manner.

[[Page 115]]

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    (c) A vessel with a discontinuous bulkhead deck. A continuous margin 
line must be drawn that is no more than 3 inches (7.6 cm) below the 
upper surface of the bulkhead deck at side as illustrated in Figure 
171.015(c).
[GRAPHIC] [TIFF OMITTED] TC01MR91.007

    (d) A vessel with a discontinuous bulkhead deck where the side shell 
is carried watertight to a higher deck. A continuous margin line must be 
drawn as illustrated in Figure 171.015(d).

[[Page 116]]

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