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Interpretation Response #24-0014

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

Interpretation Response Details

Response Publish Date:

Company Name: Precision Impacts

Individual Name: Heather Morton

Location State: OH Country: US

View the Interpretation Document

Response text:

July 9, 2024

Heather Morton
Precision Impacts
721 Richard Street
Miamisburg, OH  45342

Reference No. 24-0014

Dear Ms. Morton:

This letter is in response to your March 5, 2024, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to cylinders manufactured to International Organization for Standardization (ISO) requirements incorporated by reference (IBR) into the HMR. Specifically, you are seeking clarification and guidance regarding the "refilling" and reporting requirements of non-refillable cylinders manufactured in accordance with ISO 11118, Gas cylinders—Non-refillable metallic gas cylinders—Specification and test methods. You note the discovery of leaking valves after filling and plan to replace the defective valves and refill the cylinders.

We have paraphrased and answered your questions as follows:

Q1. You ask whether the "refilling" of cylinders manufactured to ISO 11118 standards is permissible for cylinders that have not left the manufacturing process control system.

A1. It is the opinion of this Office that cylinders that have not left the manufacturing process control system (i.e., cylinders that have not been placed into transportation for shipment to consumers) may be refilled.

Q2. You ask whether there are any provisions or exceptions within ISO 11118 or the HMR that would permit the "refilling" of these cylinders under specific circumstances if it is known that the cylinder, after production, leaked from a defective internal valve component.

A2. Please see answer A1.

Q3. You ask whether there are any requirements to document, label, and or report an activity related to an ISO 11118 cylinder that is retested and refilled.

A3. Section 13 of ISO 11118, which is titled "Test Reports and Certificate of Compliance," mandates that each batch of non-refillable cylinders, including their sealing devices, must be certified. It also requires that the cylinders conform to all ISO 11118 requirements and the test reports need to summarize all testing that has been performed. Consequently, should a cylinder be found to be leaking, the manufacturer has the option to release its contents, remove and replace the valve, and then refill and retest the cylinder. Additionally, though not explicitly required, if a leakage is discovered during testing, PHMSA recommends that the manufacturer document the actions taken for the repair and retesting of the cylinder in the test report.

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

Sincerely,

Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division

Regulation Sections