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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #11-0059 ([HazMat Resources Inc.] [Mr. Daniel G. Shelton])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: HazMat Resources Inc.

Individual Name: Mr. Daniel G. Shelton

Location State: TX Country: US

View the Interpretation Document

Response text:

October 12, 2011

 

 

 

Mr. Daniel G. Shelton

HazMat Resources Inc.

124 Rainbow Drive, # 2471

Livingston, TX 77399

Reference No.: 11-0059

Dear Mr. Shelton:

This responds to your letter regarding the requirement for the removal of the upper coupler assembly during various tests and inspections of cargo tank motor vehicles (CTMV) under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you describe two scenarios and ask several specific questions for each scenario. The questions regarding both non-insulated and insulated cargo tanks transporting a lading corrosive to the tank are paraphrased and answered as follows:

For non-insulated cargo tanks transporting a lading corrosive to the tank:

Q1: Is the upper coupler required to be removed to perform the external visual inspection?

A1: In accordance with § 180.407(d)(2)(ix), as part of the external visual inspection test for CTMVs transporting lading corrosive to the tank, an upper coupler must be removed from the CTMV and areas of the cargo tank covered by the upper coupler must be inspected for corroded and abraded areas, dents, distortions, defects in welds, and any other condition that might render the tank unsafe for transportation service. However, as stated in a previous letter of interpretation (Reference No.: 02-0290, see attached), an upper coupler may remain on the cargo tank under the following specific conditions:

1. The upper coupler must allow a complete external visual inspection of the area of the cargo tank that is directly above the upper coupler. The visual inspection must be as effective as performing an external visual inspection of this area if the turntable were to be removed.

2. The external visual inspection and pressure test must be conducted by directly viewing the tank; therefore, the use of a device that creates an image of the tank (i.e., mirrors, cameras, or fiber optics) is prohibited.



3. All major appurtenances and structural attachments on the cargo tank that can be inspected without dismantling the turntable assembly must be inspected for any corrosion or damage that might prevent safe operation (§ 180.407(d)(2)(viii)).

4. Areas covered by the turntable assembly must be inspected for corroded and abraded areas, dents, distortions, defects in welds, and any other condition that render the cargo tank unsafe for transportation service (§ 180.407(g)(1)(iii)).

Q2. Is the upper coupler required to be removed to perform the pressure test?

A2: The answer is yes, unless all the conditions and criteria in A1, 1 through 4 are met. The requirement to remove the upper coupler assembly as part of a pressure test for CTMVs was adopted into the HMR under final rule HM-183A on September 9, 1990 [55 FR 37041]. As specified in § 180.407(g)(1)(iii), except for cargo tanks carrying lading corrosive to the tank, as part of a pressure test for CTMVs, an upper coupler must be removed from the CTMV, and areas of the cargo tank covered by the upper coupler must be inspected for corroded and abraded areas, dents, distortions, defects in welds, and any other condition that might render the cargo tank unsafe for transportation. Although this requirement states "except for cargo tanks carrying material corrosive to the tank" it was not the intention of HM-183A to except these materials from removing the upper coupler during the pressure test. Instead, it was the intent to limit the requirement to remove the upper coupler for pressure testing to only CMTVs carrying material corrosive to the tank.

Q3: Is a "UC" marking, indicating the upper coupler has been inspected, required to be applied to the CTMV?

A3: The answer is no. Each cargo tank successfully completing the test and inspection requirements contained in § 180.407 must be marked as specified in § 180.415. There is no requirement in this section to mark a CTMV that has been successfully tested and inspected with "UC" marking.

For insulated cargo tanks transporting a lading corrosive to the tank:

Q4: Is the upper coupler required to be removed to perform the external visual inspection?

A4: The answer is no. In accordance with § 180.407(d)(2)(ix), as part of the external visual inspection test for CTMVs transporting lading corrosive to the tank, an upper coupler must be removed from the CTMV and areas of the cargo tank covered by the upper coupler must be inspected for corroded and abraded areas, dents, distortions, defects in welds, and any other condition that might render the tank unsafe for transportation service. However, there is no requirement to remove the insulation and jacketing covering the area of the cargo tank shell above the upper coupler. Therefore, if one did remove the upper coupler, finding any of the conditions identified in § 180.407(d)(2)(ix) would be impossible without removing the jacketing and insulation.

Q5: Is the jacketing and insulation above the upper coupler required to be removed so the shell of the cargo tank can be inspected?

A5: The answer is no. In accordance with § 180.407(d)(1), where insulation precludes a complete external visual inspection as required by paragraphs § 180.407(d)(2)-(6), the cargo tank also must be given an internal visual inspection as specified in

§ 180.407(e). If an internal visual inspection is precluded because the cargo tank is lined, coated, or designed so as to prevent access for internal inspection, the tank must be hydrostatically or pneumatically tested in accordance with § 180.407(g)(1)(iv).

Q6: Is the upper coupler required to be removed to perform the pressure test?

A6: The answer is no. In accordance with § 180.407(g)(1)(iii), except for cargo tanks carrying lading corrosive to the tank, areas covered by the upper coupler (fifth wheel) assembly must be inspected for corroded and abraded areas, dents, distortions, defects in welds, and any other condition that might render the tank unsafe for transportation service. The upper coupler (fifth wheel) assembly must be removed from the cargo tank for this inspection. However, since insulation and jacketing cover the area of the cargo tank above the upper coupler and there is no requirement to remove the insulation and jacketing, unless it is otherwise impossible to reach test pressure and maintain a condition of pressure equilibrium after the test pressure is reached or the vacuum integrity of the insulation space cannot be maintained, there are no requirements to remove the upper coupler to inspect areas of the cargo tank shell above the upper coupler that are not visible.

Q7: Is the jacketing and insulation above the upper coupler required to be removed so the shell of the cargo tank can be inspected?

A7: The answer is no. In accordance with § 180.407(g)(2), when pressure testing an insulated cargo tank, the insulation and jacketing need not be removed unless it is otherwise impossible to reach test pressure and maintain a condition of pressure equilibrium after test pressure is reached, or the vacuum integrity cannot be maintained in the insulation space.

I hope this satisfies your inquiry. Please contact us if we can be of further assistance.

Sincerely,

T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division

180.407

Regulation Sections

Section Subject
180.407 Requirements for test and inspection of specification cargo tanks