[Code of Federal Regulations]
[Title 46, Volume 1]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 46CFR38.05-2]

[Page 495-496]
 
                           TITLE 46--SHIPPING
 
         CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY
 
PART 38_LIQUEFIED FLAMMABLE GASES--Table of Contents
 
                  Subpart 38.05_Design and Installation
 
Sec. 38.05-2  Design and construction of cargo tanks--general--TB/ALL.

    (a) The maximum allowable temperature of the cargo is defined as the 
boiling temperature of the liquid at a pressure equal to the setting of 
the relief valve.
    (b) The service temperature is the minimum temperature at which 
cargo is loaded and/or transported in the cargo tank. However, the 
service temperature shall in no case be taken higher than given by the 
following formula:

ts=tw-0.25(tw-tb) (1)

where:

ts=Service temperature.
tw=Boiling temperature of gas at normal working pressure of 
tank but not higher than +32 [deg]F.
tb=Boiling temperature of gas at atmospheric pressure.

    (c) Heat transmission studies, where required, shall assume the 
minimum ambient temperatures of 0[deg] F. still air and 32[deg] F. still 
water, and maximum

[[Page 496]]

ambient temperatures of 115[deg] F. still air and 90[deg] F. still 
water.
    (d) Cargo tanks in vessels in ocean; Great Lakes; lakes, bays, and 
sounds; or coastwise service shall be designed to withstand, 
simultaneously, the following dynamic loadings:
    (1) Rolling 30[deg] each side (120[deg]) in 10 seconds.
    (2) Pitching 6[deg] half amplitude (24[deg]) in 7 seconds.
    (3) Heaving L/80[foot] half amplitude (L/20[foot]) in 8 seconds.
    (e) Cargo tanks on barges shall be designed in accordance with Sec. 
32.63-25 of this subchapter.
    (f) Each liquefied flammable gas tank shall be provided with not 
less than a 15-inch by 23-inch or an 18-inch nominal diameter manhole 
fitted with a cover located above the maximum liquid level and as close 
to the top of the tank as possible. Where access trunks are fitted to 
the tanks, the nominal diameter of the trunks shall be not less than 30 
inches.
    (g) Cargo tanks vented above 10 pounds per square inch gage shall be 
of the pressure vessel type.