[Code of Federal Regulations]
[Title 49, Volume 2]
[Revised as of October 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR180.605]

[Page 1100-1104]
 
                        TITLE 49--TRANSPORTATION
 
 CHAPTER I--RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION, DEPARTMENT OF 
                             TRANSPORTATION
 
PART 180_CONTINUING QUALIFICATION AND MAINTENANCE OF PACKAGINGS--Table of 
Contents
 
        Subpart G_Qualification and Maintenance of Portable Tanks
 
Sec.  180.605  Requirements for periodic testing, inspection and repair 
of portable tanks.

    (a) A portable tank constructed in accordance with a DOT 
specification for which a test or inspection specified in this subpart 
has become due, must be tested or inspected prior to being returned for 
transportation.
    (b) Conditions requiring test and inspection of portable tanks. 
Without regard to any other test or inspection requirements, a 
Specification or UN portable tank must be tested and inspected in 
accordance with this section prior to further use if any of the 
following conditions exist:
    (1) The portable tank shows evidence of dents, corroded or abraded 
areas, leakage, or any other condition that might render it unsafe for 
transportation service.
    (2) The portable tank has been in an accident and has been damaged 
to an extent that may adversely affect its ability to retain the 
hazardous material.
    (3) The portable tank has been out of hazardous materials 
transportation service for a period of one year or more.
    (4) The portable tank has been modified from its original design 
specification.
    (5) The portable tank is in an unsafe operating condition based on 
the existence of probable cause.
    (c) Schedule for periodic inspections and tests. Each Specification 
portable tank must be tested and inspected in accordance with the 
following schedule:

[[Page 1101]]

    (1) Each IM or UN portable tank must be given an initial inspection 
and test before being placed into service, a periodic inspection and 
test at least once every 5 years, and an intermediate periodic 
inspection and test at least every 2.5 years following the initial 
inspection and the last 5 year periodic inspection and test.
    (2) Each Specification 51 portable tank must be given a periodic 
inspection and test at least once every five years.
    (3) Each Specification 56 or 57 portable tank must be given a 
periodic inspection and test at least once every 2.5 years.
    (4) Each Specification 60 portable tank must be given a periodic 
inspection and test at the end of the first 4-year period after the 
original test; at least once every 2 years thereafter up to a total of 
12 years of service; and at least once annually thereafter. Retesting is 
not required on a rubber-lined tank except before each relining.
    (d) Intermediate periodic inspection and test. For IM and UN 
portable tanks the intermediate 2.5 year periodic inspection and test 
must include at least an internal and external examination of the 
portable tank and its fittings taking into account the hazardous 
materials intended to be transported; a leakage test; and a test of the 
satisfactory operation of all service equipment. Sheathing, thermal 
insulation, etc. need only be removed to the extent required for 
reliable appraisal of the condition of the portable tank. For portable 
tanks intended for the transportation of a single hazardous material, 
the internal examination may be waived if it is leakage tested in 
accordance with the procedures in paragraph (h) of this section prior to 
each filling, or if approved by the Associate Administrator. Portable 
tanks used for dedicated transportation of refrigerated liquefied gases 
that are not fitted with inspection openings are excepted from the 
internal inspection requirement.
    (e) Periodic inspection and test. The 5 year periodic inspection and 
test must include an internal and external examination and, unless 
excepted, a pressure test as specified in this section. Sheathing, 
thermal insulation, etc. need only to be removed to the extent required 
for reliable appraisal of the condition of the portable tank. Except for 
DOT Specification 56 and 57 portable tanks, reclosing pressure relief 
devices must be removed from the tank and tested separately unless they 
can be tested while installed on the portable tank. For portable tanks 
where the shell and equipment have been pressure-tested separately, 
after assembly they must be subjected together to a leakage test and 
effectively tested and inspected for corrosion. Portable tanks used for 
the transportation of refrigerated, liquefied gases are excepted from 
the requirement for internal inspection and the hydraulic pressure test 
during the 5-year periodic inspection and test, if the portable tanks 
were pressure tested to a minimum test pressure of 1.3 times the design 
pressure using an inert gas as prescribed in Sec.  178.338-16(a) and (b) 
of this subchapter before putting the portable tank into service 
initially and after any exceptional inspections and tests specified in 
paragraph (f) of this section.
    (f) Exceptional inspection and test. The exceptional inspection and 
test is necessary when a portable tank shows evidence of damaged or 
corroded areas, or leakage, or other conditions that indicate a 
deficiency that could affect the integrity of the portable tank. The 
extent of the exceptional inspection and test must depend on the amount 
of damage or deterioration of the portable tank. It must include at 
least the inspection and a pressure test according to paragraph (e) of 
this section. Pressure relief devices need not be tested or replaced 
unless there is reason to believe the relief devices have been affected 
by the damage or deterioration.
    (g) Internal and external examination. The internal and external 
examinations must ensure that:
    (1) The shell is inspected for pitting, corrosion, or abrasions, 
dents, distortions, defects in welds or any other conditions, including 
leakage, that might render the portable tank unsafe for transportation;
    (2) The piping, valves, and gaskets are inspected for corroded 
areas, defects, and other conditions, including

[[Page 1102]]

leakage, that might render the portable tank unsafe for filling, 
discharge or transportation;
    (3) Devices for tightening manhole covers are operative and there is 
no leakage at manhole covers or gaskets;
    (4) Missing or loose bolts or nuts on any flanged connection or 
blank flange are replaced or tightened;
    (5) All emergency devices and valves are free from corrosion, 
distortion and any damage or defect that could prevent their normal 
operation. Remote closure devices and self-closing stop-valves must be 
operated to demonstrate proper operation;
    (6) Required markings on the portable tank are legible and in 
accordance with the applicable requirements; and
    (7) The framework, the supports and the arrangements for lifting the 
portable tank are in satisfactory condition.
    (h) Pressure test procedures for specification 51, 57, 60, IM or UN 
portable tanks. (1) Each Specification 57 portable tank must be leak 
tested by a minimum sustained air pressure of at least 3 psig applied to 
the entire tank. Each Specification 51 or 56 portable tank must be 
tested by a minimum pressure (air or hydrostatic) of at least 2 psig or 
at least one and one-half times the design pressure (maximum allowable 
working pressure, or re-rated pressure) of the tank, whichever is 
greater. The leakage test for portable tanks used for refrigerated 
liquefied gas must be performed at 90% of MAWP. Leakage tests for all 
other portable tanks must be at a pressure of at least 25% of MAWP. 
During each air pressure test, the entire surface of all joints under 
pressure must be coated with or immersed in a solution of soap and 
water, heavy oil, or other material suitable for the purpose of 
detecting leaks. The pressure must be held for a period of time 
sufficiently long to assure detection of leaks, but in no case less than 
five minutes. During the air or hydrostatic test, relief devices may be 
removed, but all the closure fittings must be in place and the relief 
device openings plugged. Lagging need not be removed from a lagged tank 
if it is possible to maintain the required test pressure at constant 
temperature with the tank disconnected from the source of pressure.
    (2) Each Specification 60 portable tank must be retested by 
completely filling the tank with water or other liquid having a similar 
viscosity, the temperature of the liquid must not exceed 37.7 [deg]C 
(100 [deg]F) during the test, and applying a pressure of 60 psig. The 
portable tank must be capable of holding the prescribed pressure for at 
least 10 minutes without leakage, evidence of impending failure, or 
failure. All closures shall be in place while the test is made and the 
pressure shall be gauged at the top of the tank. Safety devices and/or 
vents shall be plugged during this test.
    (3) Each Specification IM or UN portable tank, except for UN 
portable tanks used for non-refrigerated and refrigerated liquefied 
gases, and all piping, valves and accessories, except pressure relief 
devices, must be hydrostatically tested with water, or other liquid of 
similar density and viscosity, to a pressure not less than 150% of its 
maximum allowable working pressure. UN portable tanks used for the 
transportation of non-refrigerated liquefied gases must be 
hydrostatically tested with water, or other liquid of similar density 
and viscosity, to a pressure not less than 130% of its maximum allowable 
working pressure. UN portable tanks used for the transportation of 
refrigerated liquefied gases may be tested hydrostatically or 
pneumatically using an inert gas to a pressure not less than 1.3 times 
the design pressure. For pneumatic testing, due regard for protection of 
all personnel must be taken because of the potential hazard involved in 
such a test. The pneumatic test pressure in the portable tank must be 
reached by gradually increasing the pressure to one-half of the test 
pressure. Thereafter, the test pressure must be increased in steps of 
approximately one-tenth of the test pressure until the required test 
pressure has been reached. The pressure must then be reduced to a value 
equal to four-fifths of the test pressure and held for a sufficient time 
to permit inspection of the portable tank for leaks. The minimum test 
pressure for a portable tank is determined on the basis of the hazardous 
materials that are intended to be transported in the portable

[[Page 1103]]

tanks. For liquid, solid and non-refrigerated liquefied gases, the 
minimum test pressure for specific hazardous materials are specified in 
the applicable T Codes assigned to a particular hazardous material in 
the Sec.  172.101 Table of this subchapter. While under pressure the 
tank shall be inspected for leakage, distortion, or any other condition 
which might render the tank unsafe for service. A portable tank fails to 
meet the requirements of the pressure test if, during the test, there is 
permanent distortion of the tank exceeding that permitted by the 
applicable specification; if there is any leakage; or if there are any 
deficiencies that would render the portable tank unsafe for 
transportation. Any portable tank that fails must be rejected and may 
not be used again for the transportation of a hazardous material unless 
the tank is adequately repaired, and, thereafter, a successful test is 
conducted in accordance with the requirements of this paragraph. An 
approval agency shall witness the hydrostatic or pneumatic test. Any 
damage or deficiency that might render the portable tank unsafe for 
service shall be repaired to the satisfaction of the witnessing approval 
agency. The repaired tank must be retested to the original pressure test 
requirements. Upon successful completion of the hydrostatic or pneumatic 
test, as applicable, the witnessing approval agency shall apply its 
name, identifying mark or identifying number in accordance with 
paragraph (k) of this section.
    (i) Rejection criteria. When evidence of any unsafe condition is 
discovered, the portable tank may not be returned to service until it 
has been repaired and the pressure test is repeated and passed.
    (j) Repair. The repair of a portable tank is authorized, provided 
such repairs are made in accordance with the requirements prescribed in 
the specification for the tank's original design and construction. In 
addition to any other provisions of the specification, no portable tank 
may be repaired so as to cause leakage or cracks or so as to increase 
the likelihood of leakage or cracks near areas of stress concentration 
due to cooling metal shrinkage in welding operations, sharp fillets, 
reversal of stresses, or otherwise. No field welding may be done except 
to non-pressure parts. Any cutting, burning or welding operations on the 
shell of an IM or UN portable tank must be done with the approval of the 
approval agency and be done in accordance with the requirements of this 
subchapter, taking into account the pressure vessel code used for the 
construction of the shell. A pressure test to the original test pressure 
must be performed after the work is completed.
    (k) Inspection and test markings. (1) Each IM or UN portable tank 
must be durably and legibly marked, in English, with the date (month and 
year) of the last pressure test, the identification markings of the 
approval agency witnessing the test, when required, and the date of the 
last visual inspection. The marking must be placed on or near the metal 
identification plate, in letters and numerals of not less than 3 mm 
(0.118 inches) high when on the metal identification plate, and 12 mm 
(0.47 inches) high when on the portable tank.
    (2) Each Specification DOT 51, 56, 57 or 60 portable tank must be 
durably and legibly marked, in English, with the date (month and year) 
of the most recent periodic retest. The marking must be placed on or 
near the metal certification plate and must be in accordance with Sec.  
178.3 of this subchapter. The letters and numerals must not be less than 
3 mm (0.118 inches) high when on the metal certification plate, and 12 
mm (0.47 inches) high when on the portable tank, except that a portable 
tank manufactured under a previously authorized specification may 
continue to be marked with smaller markings if originally authorized 
under that specification (for example, DOT Specification 57 portable 
tanks).
    (l) Record retention. The owner of each portable tank or his 
authorized agent shall retain a written record of the date and results 
of all required inspections and tests, including an ASME manufacturer's 
date report, if applicable, and the name and address of the person 
performing the inspection or test, in accordance with the applicable 
specification. The manufacturer's data report, including a 
certificate(s) signed

[[Page 1104]]

by the manufacturer, and the authorized design approval agency, as 
applicable, indicating compliance with the applicable specification of 
the portable tank, must be retained in the files of the owner, or his 
authorized agent, during the time that such portable tank is used for 
such service, except for Specifications 56 and 57 portable tanks.

[Amdt. 180-2, 54 FR 25032, June 12, 1989, as amended at 67 FR 15744, 
Apr. 3, 2002; 68 FR 45042, July 31, 2003]

   Appendix A to Part 180--Internal Self-closing Stop Valve Emergency 
               Closure Test for Liquefied Compressed Gases

    1. In performing this test, all internal self-closing stop valves 
must be opened. Each emergency discharge control remote actuator (on-
truck and off-truck) must be operated to ensure that each internal self-
closing stop valve's lever, piston, or other valve indicator has moved 
to the closed position.
    2. On pump-actuated pressure differential internal valves, the 
three-way toggle valve handle or its cable attachment must be activated 
to verify that the toggle handle moves to the closed position.

[64 FR 28052, May 24, 1999, as amended at 67 FR 15744, Apr. 3, 2002]

  Appendix B to Part 180--Acceptable Internal Self-closing Stop Valve 
  Leakage Tests for Cargo Tanks Transporting Liquefied Compressed Gases

    For internal self-closing stop valve leakage testing, leakage is 
defined as any leakage through the internal self-closing valve or to the 
atmosphere that is detectable when the valve is in the closed position. 
On some valves this will require the closure of the pressure by-pass 
port.

                          (a) Meter Creep Test.

    1. An operator of a cargo tank equipped with a calibrated meter may 
check the internal self-closing stop valve for leakage through the valve 
seat using the meter as a flow measurement indicator. The test is 
initiated by starting the delivery process or returning product to the 
cargo tank through the delivery system. This may be performed at an 
idle. After the flow is established, the operator closes the internal 
self-closing stop valve and monitors the meter flow. The meter flow must 
stop within 30 seconds with no meter creep within 5 seconds after the 
meter stops.
    2. On pump-actuated pressure differential internal self-closing stop 
valves, the valve must be closed with the remote actuator to assure that 
it is functioning. On other types of internal self-closing stop valves, 
the valve(s) may be closed using either the normal valve control or the 
discharge control system (e.g., remote).
    3. Rejection criteria: Any detectable meter creep within the first 
five seconds after initial meter stoppage.

               (b) Internal Self-Closing Stop Valve Test.

    An operator of a cargo tank that is not equipped with a meter may 
check the internal self-closing stop valve(s) for leakage as follows:
    1. The internal self-closing stop valve must be in the closed 
position.
    2. All of the material in the downstream piping must be evacuated, 
and the piping must be returned to atmospheric temperature and pressure.
    3. The outlet must be monitored for 30 seconds for detectable 
leakage.
    4. Rejection criteria. Any detectable leakage is considered 
unacceptable.

[64 FR 28052, May 24, 1999]

                        PARTS 181-185 [RESERVED]