# AMETEK AMERON — Hazardous Materials Safety Interpretation **Citation:** 24-0010 **Type / status:** guidance / guidance **Agency:** Pipeline and Hazardous Materials Safety Administration **Effective:** Not stated **Published:** 2024-05-10 24-0010 response to AMETEK AMERON concerning 171.8, 173.25. ## Document text <<>> U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, DC 20590 May 10, 2024 Mr. Patrick Schoenhoff General Manager AMETEK AMERON 10271 Bach Boulevard Saint Louis, MO 63132 Reference No. 24-0010 Dear Mr. Schoenhoff: This letter is in response to your February 20, 2024, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the overpack marking requirements in § 173.25 as they relate to cylinders. We have paraphrased and answered your questions as follows: Q1. You present a scenario where oxygen is shipped in Department of Transportation (DOT) 3AA or 3HT specification cylinders, placed in a fiberboard box, and marked “UN1072, Oxygen, Compressed.” You ask whether the fiberboard box must be marked “OVERPACK” as described in § 173.25(a)(4). A1. The answer is yes, provided the configuration meets the definition of an overpack, as defined in § 171.8, and the specification markings on the cylinders are not visible through the overpack. As prescribed in § 173.25(a)(4), the word “OVERPACK” is required to be marked on an overpack if package specification markings—when required—are not visible. Q2. In connection to question Q1, you ask whether it is a violation of the HMR to mark a fiberboard box with “OVERPACK” if it does not meet the definition of an overpack as defined in § 171.8. A2. The answer is yes. Marking a fiberboard box with “OVERPACK” is a violation of the HMR if it does not meet the definition of an overpack as defined in § 171.8. <<>> Q3. You present a scenario where fire extinguishers are shipped under DOT Special Permits (SPs)—DOT SP-7945, 1 DOT SP-8495, 2 and DOT SP-127263 —and marked “UN1044, Fire Extinguishers.” You ask whether the “OVERPACK” mark is required on the fiberboard box containing fire extinguisher cylinders shipped under DOT SP-7945, DOT SP-8495, and DOT SP-12726. A3. Except when transported in DOT specification cylinders (see DOT-SP 12726 paragraph 7.a), the answer is no. The SPs referenced in your letter—DOT SP-7945 and DOT SP-8495—state: “non-DOT specification cylinder conforming with all regulations applicable to a DOT specification 4DS cylinder. ” Though specification 4DS cylinders do require the “OVERPACK” marking when enclosed in a fiberboard box, in accordance with § 173.25(a)(4), the overpack marking is not required for DOT-SP 7945 and DOT-SP 8495, since the cylinders in question are not considered to be DOT specification cylinders (please also see answer A4). As such, the “OVERPACK” marking is also not required under DOT SP-12726, when non-DOT specification cylinders are used as specified in paragraph 7.a. Q4. In connection to question Q3, you ask whether it is a violation of the HMR to mark a fiberboard box with “OVERPACK” if it does not meet the definition of an overpack as defined in § 171.8. A4. See answer A2. However, when the SP requires the use of a strong outer packaging—as in DOT-SP 7945 paragraph 8.g. or DOT-SP 8495 paragraph 8.g.—the outer packaging does not meet the definition of an overpack, and therefore, “OVERPACK” is not an appropriate marking. Also note, DOT-SP 12726 paragraph 7.a. authorizes the use of both non-DOT specification cylinders and DOT specification cylinders, and—when DOT specification cylinders are used—the “OVERPACK” marking is required unless the markings representative of each package type contained in the overpack are visible from outside of the overpack. I hope this information is helpful. Please contact us if we can be of further assistance. Sincerely, Steven Andrews Acting Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division 1 https://www.phmsa.dot.gov/hazmat/documents/offer/SP7945.pdf/2022024177/SP7945 2 https://www.phmsa.dot.gov/hazmat/documents/offer/SP8495.pdf/2021114098/SP8495 3 https://www.phmsa.dot.gov/hazmat/documents/offer/SP12726.pdf/2020064323/SP12726 <<>> Pollack From: INFOCNTR (PHMSA) To: Dodd, Alice (PHMSA) Cc: Hazmat Interps Subject: FW: Overpack Interpretation Request Date: Friday, February 23, 2024 2:13:21 PM Attachments: image001.png image002.png image003.png Overpack Clarification Request.pdf 24-0010 Hi Alice, Please see the attached interpretation request. Let us know if you need anything. Sincerely, Janaye From: Patrick Schoenhoff Sent: Tuesday, February 20, 2024 2:23 PM To: PHMSA HM InfoCenter Subject: Overpack Interpretation Request CAUTION: This email originated from outside of the Department of Transportation (DOT). Do not click on links or open attachments unless you recognize the sender and know the content is safe. Hello, Please see the attached request for Interpretation of the use of Overpack labels on packages containing charged cylinders. Feel free to contact me with any questions you have with this request. Best regards, Patrick Schoenhoff Technical Director / General Manager D: +1 314 428 2062 x1077 | 10271 Bach Boulevard Saint Louis, MO 63132 www.ameronglobal.com O: +1 314 428 2062 | E: patrick.schoenhoff@ametek.com <<>> This email, and any files transmitted with it, are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error, please notify the sender and delete this email. If you are not the intended recipient, you are notified that disclosing, copying, distributing, or taking any action in reliance on the contents of this information, is strictly prohibited. <<>> AMERON 10271 BACH BOULEVARD SAINT LOUIS. MO 63132 314-428-2062 PH February 20, 2024 Mr. Shane Kelley Director, Standards and Rulemaking Division U.S. DOT/PHMSA (PHH-10) 1200 New Jersey Avenue, SE East Building, 2nd Floor Washington, DC 20590 Mr. Kelley, I am requesting a Letter of Interpretation for the Overpack labeling of packages in the following scenarios. Scenario 1: An Oxygen Cylinder with a DOT rating of either 3AA or 3HT is packaged in a fiberboard box. The box is marked with UN1072 Oxygen, Compressed labels. Question 1: Does the above packaging constitute being labeled as an “Overpack”? Question 2: If not meeting the definition or requirement of an “Overpack”, is marking the box as an Overpack a violation of the regulations? Scenario 2: A Fire Extinguisher Cylinder with a DOT SP rating of SP-8495 or SP- 7945 is packaged in a fiberboard box. The box is marked with UN1044, Fire Extinguishers SP-12726 labels and then shipped per SP-12726 (of which we hold Party Status). Question 3: Does the above packaging constitute being labeled as an “Overpack” with an SP cylinder? Question 4: If not meeting the definition or requirement of an “Overpack”, is marking the box as an Overpack a violation of the regulations? Thank you for your help on this matter, and feel free to contact me if you have any questions regarding these scenarios. Best Regards, Patrick Schoenhoff General Manager AMETEK AMERON 10271 Bach Boulevard Saint Louis, MO 63132 314-428-2062 X1077 E-mail: patrick.schoenhoff@ametek.com ## Provenance - Official: Yes - Source: - Source ID: `phmsa` - SHA-256: `068eef09ec4a385ad0d9efa45efd989eeceec6090e410cb684067060c1360959` - Retrieved: 2026-08-20T00:59:31.977Z - Exported: 2026-08-22T16:37:23.708Z - Document slug: `phmsa-interpretation-24-0010` ### Source metadata ```json { "materialSubtype": "interpretation", "interpretationArea": "hazardous_materials", "representation": "full_text_from_official_pdf", "companies": [ "AMETEK AMERON" ], "individuals": [ "Patrick Schoenhoff" ], "refIds": [ "24-0010" ], "catalogDates": [ "2024-05-10" ], "catalogParts": [ 171, 173 ], "catalogRowCount": 2, "sourceRecordUrls": [ "https://www.phmsa.dot.gov/node/74731" ], "linkedAttachmentUrls": [], "unavailableResponseUrls": [], "duplicateRepresentationUrls": [], "citedSections": [ "171.8", "173.25" ], "catalogPageUrls": [ "https://www.phmsa.dot.gov/regulations/title49/section/1718", "https://www.phmsa.dot.gov/regulations/title49/section/17325" ], "pdfUrls": [ "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2024-05/240010.pdf" ], "representations": [ { "viewUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2024-05/240010.pdf", "detailUrl": null, "detailHtmlPath": null, "pdfUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/2024-05/240010.pdf", "pdfArtifactPath": "data/sources/phmsa-interpretations/24-0010-57452607be.pdf", "pdfArtifactSha256": "71b65b10a3d8f6635ece65c0fc71e6eee946ad4b90da70e9e148f8d38af56096", "extractedTextPath": "data/sources/phmsa-interpretations/24-0010-57452607be.v2.txt", "extractedTextSha256": "afaac9e74f304433f8c56dbed78612c0e0b103b36eb3a434d10c059fad56e7c6", "pageCount": 5, "extractionVersion": 2 } ], "caveat": "Interpretations apply regulations to the facts presented and do not create independently enforceable requirements.", "jurisdiction": "US" } ```