# National Aquatic Service, Inc. — Hazardous Materials Safety Interpretation **Citation:** 11-0151 **Type / status:** guidance / guidance **Agency:** Pipeline and Hazardous Materials Safety Administration **Effective:** Not stated **Published:** 2011-08-25 11-0151 response to National Aquatic Service, Inc. concerning 173.302a, 180.205. ## Document text <<>> u.s. Department 1200 New Jersey Avenue SE of Transportation Washington. DC 20590 Pipeline and Hazardous Materials Safety AUG 252011 Administration Mr. Michael Druce National Aquatic Service, Inc. 1732 Erie Blvd. East Syracuse, NY 13210-1296 Reference No.: 11-0151 Dear Mr. Druce: This responds to your letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the requalification and use of Department of Transportation (DOT) specification cylinders. Your questions are paraphrased and answered as follows: Q1. Is it required to compute the average and maximum wall stress limitations using the formulas provided in § 173.302a(b )(3) when the Relative Elastic Expansion (REE) has been marked on the cylinder by the manufacturer? AI. The answer is no. In accordance with § 173.302a(b)(3), either the average wall stress or the maximum wall stress can be used to determine compliance; both calculations are not required. Furthermore, in addition to the formula provided in § 173.302a(b )(3)(i)(A), compliance with the average wall stress limitation may be determined by computing the elastic expansion rejection limit in accordance with Compressed Gas Association (CGA) pamphlet C-5, by reference to data tabulated in CGA C-5, or by the manufacturer's marked elastic expansion rejection limit (REE) on the cylinder. It should be noted however, that if the maximum wall stress is used to determine compliance with § 173.302a(b)(3), the formula provided in § 173.302a(b )(3)(ii) must be used to determine the maximum wall stress. Q2. If a facility only plus (+) stamps cylinders based on the REE marked on the cylinder by the manufacturer, is it necessary to have a copy of CGA C-5? A2. The answer is no. There is no requirement in the HMR mandating a facility to retain a copy of CGA C-5. However, if a facility is using CGA C-5 as the method to compute the average wall stress limitation, in accordance with § 173.302a(b )(3)(iii), that facility should have access to a CGA C-5. Q3. Must an authorized retesting facility notify itself in writing of the condemnation when a cylinder owned by that facility, such as a cylinder used for rental purposes, fails periodic requalification? <<>> A3. The answer is no. In accordance with 180.205(i)(3), the requalifier of a cylinder must notify the cylinder owner, in writing, that the cylinder is condemned and may not be filled with hazardous material and offered for transportation in commerce where use of a specification packaging is required. However, if an authorized retesting facility is also the owner of the condemned cylinder it is not the intention of the HMR to require self notification. Q4. If the owner of a condemned cylinder relinquishes ownership of that condemned cylinder to the retesting facility for disposal or destruction, must the retesting facility disposing or destroying the cylinder notify the now former owner in writing of that cylinder's condemnation? A4. The answer is no. In accordance with 180.205(i)(3), the requalifier of a cylinder must notify the cylinder owner, in writing, that the cylinder is condemned and may not be filled with hazardous material and offered for transportation in commerce where use of a specification packaging is required. If the condemned cylinder is relinquished by a facility that is both the owner and requalifier to a subsequent facility for disposal or destruction, no notification would be required. 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 <<>> National Aquatic Service, Inc 1732 Erie Blvd East Syracuse, NY 13210-1296 3154795544 www.nationalaquatic.com 315479 5766 fax info@nationalaquatic.com BOO SEA DIVE Bened·{~+, ~ /18. 302~(h'M) 5 I ~o .UJ5 (;)(3) ~/,nd(~ 11-0/5/ June 2, 2011 U.S. DOT PHMSA Office of Hazardous Materials Standards Attn: PHH-I0 East Building 1200 New Jersey Avenue, SE. Washington, DC 20590-0001 RE: Request for Interpretation{s) To Whom It May Concern: National Aquatic Service, Inc. (RINC234) is a SCUBA diving facility. During a recent inspection, the following issues of interpretation arose. 1. Regarding Wall Stress Calculation requirements of §173.302a(b)(3). a. Is it required to compute average and/or.maximum wall stress calculations when the REE is marked on the cylinder by the manufacturer? b. If a facility only Plus (+) stamps cylinders with the REE marked on the cylinder by the manufacturer, is it necessary to have a copy of CGA C-5? 2. Regarding notification of cylinder owner in writing when a cylinder must be condemned of § 1 BO.205(i){3) a. Must an authorized retesting facility, a SCUBA facility, notify itself in writing of the condemnation when a cylinder owned by that facility, such as a cylinder used for rental purposes, fails periodic requalification? b. If the owner of a condemned cylinder relinqUishes ownership of that cylinder to the retesting facility for disposal, must the retester 'notify the now former owner in writing of that cylinder's condemnation? <<>> National Aquatic Service, Inc 1 732 Erie Blvd East Syracuse, NY 13210-1296 315 479 5544 www.nationalaquatic.com 3154795766 fax info@nationalaquatic.com 800 SEA DIVE Please contact me if you have any questions. Thank you for you assistance in this matter. Sincerely, Michael Druce Facility Manager RINC234 National Aquatic Service, Inc ## Provenance - Official: Yes - Source: - Source ID: `phmsa` - SHA-256: `1987708a63447a89753e0d5d46b73b6a37db0932f8de2b2739ea1c39a3113d5d` - Retrieved: 2026-08-20T00:59:31.977Z - Exported: 2026-08-23T10:58:42.241Z - Document slug: `phmsa-interpretation-11-0151` ### Source metadata ```json { "materialSubtype": "interpretation", "interpretationArea": "hazardous_materials", "representation": "full_text_from_official_pdf", "companies": [ "National Aquatic Service, Inc." ], "individuals": [ "Mr. Michael Druce" ], "refIds": [ "11-0151" ], "catalogDates": [ "2011-08-25" ], "catalogParts": [ 173, 180 ], "catalogRowCount": 2, "sourceRecordUrls": [ "https://www.phmsa.dot.gov/node/55206" ], "linkedAttachmentUrls": [], "unavailableResponseUrls": [], "duplicateRepresentationUrls": [], "citedSections": [ "173.302a", "180.205", "180.205(i)(3)" ], "catalogPageUrls": [ "https://www.phmsa.dot.gov/regulations/title49/section/173302a", "https://www.phmsa.dot.gov/regulations/title49/section/180205" ], "pdfUrls": [ "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretations/2011/110151.pdf" ], "representations": [ { "viewUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretations/2011/110151.pdf", "detailUrl": null, "detailHtmlPath": null, "pdfUrl": "https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretations/2011/110151.pdf", "pdfArtifactPath": "data/sources/phmsa-interpretations/11-0151-15c18f878c.pdf", "pdfArtifactSha256": "80c0a615b26760b6153047ea656bb25b576838949cbda88df5b193a3b81856f9", "extractedTextPath": "data/sources/phmsa-interpretations/11-0151-15c18f878c.v2.txt", "extractedTextSha256": "9bf8e0c69b06e896391c7319ded619f01e596b54edc76ef72652b0d107dbedbf", "pageCount": 4, "extractionVersion": 2 } ], "caveat": "Interpretations apply regulations to the facts presented and do not create independently enforceable requirements.", "jurisdiction": "US" } ```