[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: 46CFR38.25-1]

[Page 507-508]
 
                           TITLE 46--SHIPPING
 
         CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY
 
PART 38_LIQUEFIED FLAMMABLE GASES--Table of Contents
 
              Subpart 38.25_Periodic Tests and Inspections
 
Sec. 38.25-1  Tests and inspections--TB/ALL.


    (a) Each tank shall be subjected to the tests and inspections 
described in this section in the presence of a marine inspector, except 
as otherwise provided in this part.
    (1) An internal inspection of the tank is conducted within--
    (i) Ten years after the last internal inspection if the tank is a 
pressure vessel type cargo tank on an unmanned barge carrying cargo at 
temperatures of -67 [deg]F (-55 [deg]C) or warmer; or
    (ii) Eight years after the last internal inspection if the tank is 
of a type other than that described in paragraph (a)(1)(i) of this 
section.
    (2) An external examination of unlagged tanks and the visible parts 
of lagged tanks shall be made at each inspection for certification and 
at such other times as considered necessary.
    (3) The owner shall ensure that the amount of insulation deemed 
necessary by the marine inspector is removed from insulated tanks during 
each internal inspection to allow spot external examination of the tanks 
and insulation, or the thickness of the tanks may be gauged by a 
nondestructive means accepted by the marine inspector without the 
removal of insulation.
    (4) If required by the Officer in Charge, Marine Inspection, the 
owner shall conduct nondestructive testing of each tank in accordance 
with Sec. 38.25-3.
    (5) If the tank is a pressure vessel type cargo tank with an 
internal inspection interval of 10 years, is 30 years old or older, 
determined from the date it was built, the owner shall conduct 
nondestructive testing of that tank, in accordance with Sec. 38.25-3, 
during each internal inspection.
    (b) If the marine inspector considers a hydrostatic test necessary 
to determine the condition of the tank, the owner shall perform the test 
at a pressure of 1\1/2\ times the tanks's--

[[Page 508]]

    (1) Maximum allowable pressure, as determined by the safety relief 
valve setting; or
    (2) Design pressure, when cargo tanks operate at maximum allowable 
pressures reduced below the design pressure in order to satisfy special 
mechanical stress relief requirements.

    Note: See the ASME Code, Section VIII, Appendix 3 for information on 
design pressure.

    (c) For pressure vessels designed and/or supported such that they 
cannot safely be filled with water, the Commandant will consider a 
pneumatic test in lieu of the hydrostatic test. A leak test shall be 
performed in conjunction with the pneumatic test. Pneumatic testing 
shall be in accordance with subchapter F (Marine Engineering) of this 
chapter.
    (d) Nonpressure vessel type tanks shall be tested to a pressure 
equal to the pressure on the bottom of the tank under the design 
conditions listed in Sec. 38.05-4(e).
    (e) In the application of the requirements for testing of the cargo 
tanks, the test shall in no case be less severe than the worst 
anticipated service condition of the cargo loading.
    (f) In the design and testing of the independent cargo tanks, 
consideration shall be given to the possibility of the independent tanks 
being subjected to external loads.

[CGFR 66-33, 31 FR 15269, Dec. 6, 1966, as amended by CGD 85-061, 54 FR 
50962, Dec. 11, 1989]