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Interpretation Response #16-0196 ([PonyPak] [Mr. William Messner])

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

Interpretation Response Details

Response Publish Date:

Company Name: PonyPak

Individual Name: Mr. William Messner

Location State: IL Country: US

View the Interpretation Document

Response text:

July 27, 2017

William Messner
P.O. Box 130
Downers Grove, IL 60515

Reference No. 16-0196

Dear Mr. Messner:

This letter is in response to your December 8, 2016, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to United Nations (UN) International Organization for Standardization (ISO) Standard 11119-2 carbon fiber composite cylinders. You state that your company plans to begin production of dive equipment incorporating carbon self-contained breathing apparatus (SCBA) cylinder tanks certified to ISO-11119-2. You further specify that while your cylinders are not used underwater, they are used on the surface in marine environments (i.e., on shore, off piers, off shore).

We have paraphrased and answered your questions as follows:

Q1. You ask whether a letter of interpretation issued under Reference No. 14-0123 that describes a scenario where ISO Standard 11119-2 cylinders do not require a special permit (DOT-SP) or competent authority (CA) approvals is applicable to other companies with the same scenario.

A1. The answer is yes. Letters of interpretation reflect the administration's current application of the HMR to the specific facts presented by the person requesting the clarification. They are provided to help the public understand how to comply with the HMR. Letters of interpretation do not create legally-enforceable rights.

As described by Reference No. 14-0123, dated November 3, 2014:

"A cylinder designed and constructed in conformance with the applicable requirements prescribed in 49 CFR 178.70, 178.71(a) and 178.71(l) for an ISO Standard 11119-2 is a UN standard fibre-reinforced, composite gas cylinder with a load sharing metal liner. Cylinders that are fully in conformance with ISO 11119-2 do not require a DOT-SP or CA Approval. To certify that these cylinders are an authorized UN standard packaging, manufacturers mark them in conformance with § 178.71(p), (q), and (r)…An ISO Standard 11119-2 cylinder that varies from this design is not an authorized packaging in the United States until its variations are reviewed and approved by PHMSA's Associate Administrator for Hazardous Materials Safety in the form of a DOT-SP or CA. The cylinder must be marked with the DOT-SP or CA number if the DOT-SP or CA requires that it be marked with that number; otherwise, the marking of that number is not required. In addition, the HMR require ISO Standard 11119-2 cylinders to be refilled in conformance with §§ 173.301, 173.301b, 173.304b; and periodically retested in conformance with § 180.205."

Please note, the marking requirements in § 178.71 of the HMR were redesignated to paragraphs (q), (r), and (s) by the final rule HM-215M published January 8, 2015 [80 FR 1075].

Q2. You ask whether the cylinders you describe in your letter, which you state are to be used on the surface in marine environments only, require the "UW" mark prescribed in §§ 173.301b(g), 178.71(l)(2) and (q)(18) for composite cylinders certified to ISO-11119-2 intended for underwater use.

A2. The answer is no, provided the cylinders are not intended for underwater use or manufactured in accordance with the requirements for underwater use (see § 178.71(l)(2)). However, the requirements to mark the "UW" may be followed as a voluntary option for cylinders which are not intended for underwater use. Therefore, it is recommended that PonyPak consider whether its use of ISO Standard 11119-2 cylinders in a marine environment warrants the use of cylinders which have been subjected to the saltwater immersion test in accordance with 8.5.11 of the Standard.

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



T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

178.70, 178.71(a), 178.71(l), 178.71(p), (q), (r), 173.301, 173.301b, 173.304b, 180.205, 178.71(l)(2)

Regulation Sections

Section Subject
173.301 General requirements for shipment of compressed gases and other hazardous materials in cylinders, UN pressure receptacles and spherical pressure vessels
173.304 Filling of cylinders with liquefied compressed gases
178.70 Approval of UN pressure receptacles
178.71 Specifications for UN pressure receptacles
180.205 General requirements for requalification of specification cylinders