[Code of Federal Regulations]
[Title 46, Volume 2]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 46CFR69.65]

[Page 394]
 
                           TITLE 46--SHIPPING
 
   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)
 
PART 69_MEASUREMENT OF VESSELS--Table of Contents
 
                 Subpart B_Convention Measurement System
 
Sec. 69.65  Calculation of volumes.

    (a) Volumes V and Vc used in calculating gross and net 
tonnages, respectively, must be measured and calculated according to 
accepted naval architectural practices for the spaces concerned.
    (b) The volume of the hull below the upper deck is determined as 
follows:
    (1) If the number and location of sections originally used in making 
other calculations which relate to the form of the vessel (such as 
displacement volumes and center of buoyancy) are reasonably available, 
Simpson's first rule may be applied using those sections.
    (2) If the number and location of stations originally used are not 
reasonably available or do not exist and the hull is of conventional 
design with faired lines, Simpson's first rule may be applied using a 
number and location of stations not less than those indicated in Sec. 
69.109(g)(1).
    (3) If the hull is of standard geometric shape, a simple geometric 
formula that yields a more accurate volume may be used.
    (4) If the lines of the hull are not fair, the volume may be 
measured by using a combination of methods under this section.
    (c) The volume of structures above the upper deck may be measured by 
applying the superstructure provisions in Sec. 69.113 or by any 
accepted method or combinations of methods.
    (d) Measurements must be taken, regardless of the fitting of 
insulation or the like--
    (1) To the inner side of the shell or structural boundary plating, 
in vessels constructed of metal; and
    (2) To the outer surface of the shell or to the inner side of 
structural boundary surfaces, in all other vessels.
    (e) When determining the volume of a cargo space, measurements must 
be taken without consideration for insulation, sparring, or ceiling 
fitted within the space.
    (f) Measurements must be to the nearest one-twentieth of a foot.
    (g) Calculations must be made on a worksheet and must be 
sufficiently detailed to permit easy review. The measurement procedures 
used must be identified on the worksheet.