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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 #23-0021

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

Interpretation Response Details

Response Publish Date:

Company Name: W. R. Grace & Co – Conn.

Individual Name: Paul Errichetti

Location State: MD Country: US

View the Interpretation Document

Response text:

July 31, 2023

Paul Errichetti
Sr. Mgr., Fleet and Dangerous Goods
W. R. Grace & Co – Conn.
7500 Grace Drive
Columbia, MD  21044

Reference No. 23-0021

Dear Mr. Errichetti:

This letter is in response to your March 6, 2023, email and subsequent phone conversations requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to Department of Transportation (DOT) specification packagings. You indicate that your company has a fleet of cylinders that were manufactured and certified as DOT-4BW cylinders; however, due to frustrations with using these packagings internationally, you prefer to test and certify them as United Nations (UN) specification steel drums (i.e., UN1A1). You note that the DOT-4BW cylinders meet the physical specifications and have passed required testing to qualify as UN1A1 steel drums, and that no physical changes are needed to meet the UN1A1 packaging standard.

We have paraphrased and answered your questions as follows:

Q1. You ask whether your company may remanufacture a cylinder—which currently meets the DOT-4BW specification standard—as now meeting the UN1A1 steel drum specification standard.

A1. The answer is yes, as the HMR does not prohibit this action. As provided in § 173.28, remanufacture includes the conversion of a packaging meeting one specification or standard to another specification or standard. Note that a person (or company) who remanufactures a non-bulk packaging to conform to a specification or standard is subject to the manufacturer's requirements outlined in Part 178 of the HMR.

Q2. You ask whether a non-bulk container may be dual-marked as a DOT-4BW cylinder and as a UN1A1 steel drum.

A2. The answer is yes. In accordance with § 178.3(c), if a packaging conforms to more than one UN standard or DOT specification, the packaging may bear more than one marking provided all requirements are met and each marking is shown in full.

Q3. You ask whether the original DOT-4BW cylinder marking may be covered up with the new UN1A1 steel drum marking.

A3. The answer is yes. Note, however, that with regard to your scenario, a packaging previously marked as representing compliance with the DOT-4BW specification but no longer maintained as such must have the marking covered or obliterated prior to its use and transportation. In your scenario, the DOT-4BW marking may be covered up by the UN1A1 specification marking in its place.

Q4. If remanufacture is permitted, you ask whether you may use a third-party agency to perform the remanufacture and validation testing.

A4. The answer is yes.

Q5. You ask whether a 58-gallon UN1A1 steel drum marked with the appropriate nominal thickness marking requires additional leakproofness tests in order to be reused.

A5. The answer is yes, unless the requirements of § 173.28(b)(7) are met—which include that the packaging:

(1) is refilled with a material which is compatible with the previous lading:
(2) is refilled and offered for transportation by the original filler;
(3) is transported in a transport vehicle or freight container under the exclusive use of the refiller of the packaging; and
(4) is constructed of stainless steel, monel, or nickel with a thickness not less than one and one-half times of the minimum thickness requirement.

Q6. You ask what package description is appropriate on the shipping paper when shipping this package if it is dual-marked as a DOT-4BW cylinder and as a UN1A1 steel drum.

A6. For a packaging that is dual-marked because it meets more than one packaging specification and type, either packaging type is appropriate when listing it on the shipping paper, provided that it is an authorized packaging for the material.

I hope this information is helpful. Please contact us if we can be of further assistance.


Shane C. Kelley
Standards and Rulemaking Division

173.28, 173.28(b)(7), 178.3(c)

Regulation Sections

Section Subject
173.28 Reuse, reconditioning and remanufacture of packagings
178.3 Marking of packagings