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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 #03-0101 ([Transportation Safety Compliance Service] [Mr. Darwin D. Garvin])

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

Interpretation Response Details

Response Publish Date:

Company Name: Transportation Safety Compliance Service

Individual Name: Mr. Darwin D. Garvin

Location State: OH Country: US

View the Interpretation Document

Response text:

Jul 16, 2003


Mr. Darwin D. Garvin               Reference No. 03-0101

Transportation Safety Compliance Service

40085 C.R.7

Caldwell, Ohio 43724

Dear Mr. Garvin:

This is in response to your letter and your telephone conversation with Mr. Darral Relerford, of the Office of Hazardous Materials Standards, concerning the transportation of sulfuric acid and the requirements for inspectors of cargo tank motor vehicles under the Hazardous Materials Regulations (HMR; 49 C.R. Parts 171-180).  Your questions are paraphrased and answered as follows:

Q1.      How must a cargo tank be protected when transporting sulfuric acid in concentrations over 65.25 percent?

Al.        As stated in § 173.24(e), it is the responsibility of any person who offers a hazardous material for transportation to ensure that the packaging is compatible with its lading.  The need for corrosion protection, if any, depends on the corrosion rate that a particular sulfuric acid concentration would have on the cargo tank material of construction.  As an example, high strength sulfuric acid reacts with carbon steel at a very slow rate.

Q2.      Is the option for "corrosive allowance" only for concentration of sulfuric acid up to 65.25 percent?

A2.      Any cargo tank may be built with corrosion allowance.   However, Special Provision B15, that applies to sulfuric acid in concentrations up to 51 percent, and Special          Provision B84, that applies to sulfuric acid in concentrations up to 65.25 percent, require the use of a cargo tank protected with non-metallic lining impervious to the lading or with a suitable corrosion allowance.  Also see   § 178.345-3(c).

Q3.      May a cargo tank motor vehicle manufacturer and repair facility that has authorization for the use of the "R"stamp issued by the National Board of Boiler and Pressure Vessel Inspectors (National Board) and the American Society of Mechanical Engineers (ASME) Certificate of Authorization "U" stamp register five separate facilities (i, e., headquarters and four field branches) under the same Department of Transportation (DOT) Registration Number?


A3.      The answer is yes, if the branch offices are legitimate extensions of the headquarter"s facility and the cargo tank manufacturing and repair work at all five facilities is performed under the supervision of personnel who are located at and dispatched from the

            same facility.  All registration records must be maintained and made available for inspection at the dispatching facility and each facility where work is performed.

However, if the manufacturing or repair work is performed at and certified by personnel stationed at the headquarter"s facility or a branch facility, then each facility where the work is performed must be registered and have a separate registration number as stated in §§ 107.502(e) and 107.503(a)(2). In addition the registration application must include, a statement indicating whether the facility uses mobile testing/inspection equipment to perform inspections, tests, or repairs at a location other than the address listed in paragraph (a)(2)of § 107.503.

Q4.      May an employee or shop personnel who is not registered as an inspector perform inspection and testing of cargo tanks?

A4.      Yes, a person who is not a Registered Inspector may perform -

a)         the inspections and tests listed in § 180.407(c) under the direct supervision of a person who is a Registered Inspector.  All inspection and test reports must be certified by the Registered Inspector. See § 180.409(a).

b)        the annual external visual inspections and leakage tests on a cargo tank motor vehicle with a capacity of less than 13,250 L (3,500 gallons) used exclusively for flammable liquid petroleum fuels if the vehicle is owned or operated by that person.  The person performing the inspections and tests or certifying the reports must have the knowledge and ability to perform such inspections and tests and must be registered with the Department under § 107.502. See § 180.409(b).

c)         the annual external visual inspections and leakage tests on a permanently mounted nonbulk tank for petroleum products as authorized by § 173.8(c) if the vehicle is owned or operated by that person.  The person performing the inspections and tests must have the knowledge and ability to perform such inspections and tests.  However, the person performing the inspections and tests and the person certifying the reports, if different, are not required to register with the Department under § 107.502. See § 180.409(c).

d)         a  portion of the hydrostatic or pneumatic pressure test as set forth in § 180.407(g)(1)(viii) and (ix), respectively.  The person must be familiar with the cargo tank, and trained and experienced in the use of the inspection and testing equipment used.  The person"s employer must be registered with the Department and must retain a copy of the tester"s qualifications in the records.  See § 180.409(d).

Q5.      May an employee who is not a registered inspector sign the inspection report?

A5.      See response A4.

I hope this information is helpful. Please contact us if you require additional assistance



Susan Gorsky

Senior Transportation Regulations Specialist

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.24 General requirements for packagings and packages