The Research and Special Programs Administration of the DOT, (RSPA), created Part 180, "The Continuing Qualification and Maintenance of Packaging" because investigations of tank truck operations revealed that, prior to 1985, many cargo tanks were not well maintained (particularly components like vents, manholes and emergency valves). There was also evidence that cargo tank vessels were poorly maintained, and repairs were often of poor quality. Incidentally, DOT's use of the word "packaging", in our case, is RSPA terminology for cargo tanks.

The use of the term "Continuing Qualifications" stems from the concept that when a cargo tank is manufactured it is "Qualified" as a hazardous materials package by the manufacturer. After varying periods of time, depending on the type tank, it must be inspected and maintained or it will no longer be "qualified".

Part 180 lays the ground rules for those inspections and required maintenance procedures necessary for a HM cargo tank to continue to be qualified and to be used in hazardous material transportation.  They may continue in service for as long as they are able to meet part 180 requirements.  This section of the Maintenance Manual is an explanation of those requirements in general. The individual sections covering Specification DOT-406/MC-306, DOT-407/MC-307, DOT-412/MC-312, MC 330/331, will explain in detail the requirements for each type. There may be some duplication. Additionally, recommendations are included for certain non-specification tanks.

In summary, Part 180 establishes six different inspections as follows: 

1. External Visual Inspection;

2. Internal Visual Inspection;

3. Lining Inspection;

4. Leakage Test;

5. Pressure Retest;

6. Thickness Test.

 Part 180 establishes minimum standards of repairs for deficiencies found as a result of inspections as well as record keeping and marking requirements for the tests and markings to put on the cargo tank to indicate the date they have passed the inspections.

In addition to mechanical requirements, Part 180 requires that Inspectors and testers must meet minimum requirements and be registered with DOT for each type test they intend to perform, and that facilities which perform welded repairs and modify cargo tanks must be registered with DOT and hold a valid ‘R’ or 'U' stamp.

When a new cargo tank is shipped, the original manufacturer may perform the original tests and may mark the tank with the appropriate letters that signify each type test. Shown below is a table of Test or Inspections required and the interval at which they are required after the original certification.

 
§ 180.407   Requirements for test and inspection of specification cargo tanks.

(a) General.

(1) A cargo tank constructed in accordance with a DOT specification for which a test or inspection specified in this section has become due, may not be filled and offered for transportation or transported until the test or inspection has been successfully completed. This paragraph does not apply to any cargo tank filled prior to the test or inspection due date.

(2) Except during a pressure test, a cargo tank may not be subjected to a pressure greater than its design pressure or MAWP.

(3) A person witnessing or performing a test or inspection specified in this section must meet the minimum qualifications prescribed in §180.409.

(4) Each cargo tank must be evaluated in accordance with the acceptable results of tests and inspections prescribed in §180.411.

(5) Each cargo tank which has successfully passed a test or inspection specified in this section must be marked in accordance with §180.415.

(6) A cargo tank which fails a prescribed test or inspection must:

(i)  Be repaired and retested in accordance with §180.413; or

(ii) Be removed from hazardous materials service and the specification plate removed, obliterated or covered in a secure manner.

(b) Conditions requiring test and inspection of cargo tanks.

Without regard to any other test or inspection requirements, a specification cargo tank must be tested and inspected in accordance with this section prior to further use if:

(1) The cargo tank shows evidence of dents, cuts, gouges, corroded or abraded areas, leakage, or any other condition that might render it unsafe for hazardous materials service. At a minimum, any area of a cargo tank showing evidence of dents, cuts, digs, gouges, or corroded or abraded areas must be thickness tested in accordance with the procedures set forth in paragraphs (i)(2), (i)(3), (i)(5), and (i)(6) of this section and evaluated in accordance with the criteria prescribed in §180.411. Any signs of leakage must be repaired in accordance with §180.413. The suitability of any repair affecting the structural integrity of the cargo tank must be determined either by the testing required in the applicable manufacturing specification or in paragraph (g)(1)(iv) of this section.

(2) The cargo tank has sustained damage to an extent that may adversely affect its lading retention capability. A damaged cargo tank must be pressure tested in accordance with the procedures set forth in paragraph (g) of this section.

(3) The cargo tank has been out of hazardous materials transportation service for a period of one year or more. Each cargo tank that has been out of hazardous materials transportation service for a period of one year or more must be pressure tested in accordance with §180.407(g) prior to further use.

(4) [Reserved]

(5) The Department so requires based on the existence of probable cause that the cargo tank is in an unsafe operating condition.

(c) Periodic test and inspection.

Each specification cargo tank must be tested and inspected as specified in the following table by an inspector meeting the qualifications in §180.409. The retest date shall be determined from the specified interval identified in the following table from the most recent inspection or the CTMV certification date.

Compliance Dates—Inspections and Test Under §180.407(C)

Test or inspection (cargo tank specification, configuration, and service) Date by which first test must be completed (see note 1) Interval period after first test
External Visual Inspection:    
All cargo tanks designed to be loaded by vacuum with full opening rear heads September 1, 1991 6 months.
All other cargo tanks September 1, 1991 1 year.
Internal Visual Inspection:    
All insulated cargo tanks, except MC 330, MC 331, MC 338 (see Note 4) September 1, 1991 1 year.
All cargo tanks transporting lading corrosive to the tank September 1, 1991 1 year.
All other cargo tanks, except MC 338 September 1, 1995 5 years.
Lining Inspection:    
All lined cargo tanks transporting lading corrosive to the tank September 1, 1991 1 year.
Leakage Test:    
MC 330 and MC 331 cargo tanks in chlorine service September 1, 1991 2 years.
All other cargo tanks except MC 338 September 1, 1991 1 year.
Pressure Test:    
(Hydrostatic or pneumatic) (See Notes 2 and 3)    
All cargo tanks which are insulated with no manhole or insulated and lined, except MC 338 September 1, 1991 1 year.
All cargo tanks designed to be loaded by vacuum with full opening rear heads September 1, 1992 2 years.
MC 330 and MC 331 cargo tanks in chlorine service September 1, 1992 2 years.
All other cargo tanks September 1, 1995 5 years.
Thickness Test:    
All unlined cargo tanks transporting material corrosive to the tank, except MC 338 September 1, 1992 2 years.

Note 1:

If a cargo tank is subject to an applicable inspection or test requirement under the regulations in effect on December 30, 1990, and the due date (as specified by a requirement in effect on December 30, 1990) for completing the required inspection or test occurs before the compliance date listed in table I, the earlier date applies.

Note 2:

Pressure testing is not required for MC 330 and MC 331 cargo tanks in dedicated sodium metal service.

Note 3:

Pressure testing is not required for uninsulated lined cargo tanks, with a design pressure or MAWP 15 psig or less, which receive an external visual inspection and lining inspection at least once each year.

Note 4:

Insulated cargo tanks equipped with manholes or inspection openings may perform either an internal visual inspection in conjunction with the external visual inspection or a hydrostatic or pneumatic pressure-test of the cargo tank.

 

 

 

 

Please contact us with any repair or service work you may have:

Ed Mansell              -   General Manager
 

 

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