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Interpretation Response #18-0143

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

Interpretation Response Details

Response Publish Date:

Company Name: American Cylinder and Safety

Individual Name: Myles L. TenBroeck

Location State: TX Country: US

View the Interpretation Document

Response text:

April 16, 2019

Myles L. TenBroeck
American Cylinder and Safety
P.O. Box 126
Iowa Park, TX  76367

Reference No. 18-0143

Dear Mr. TenBroeck:

This letter is in response to your November 20, 2018, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to epoxy labels used to mark cylinders. Specifically, you provide the following scenario and ask whether the label embedded in epoxy can be reapplied to the cylinder:

  • A DOT specification 3A, 3AA, or 3AL cylinder is successfully requalified in accordance with the HMR.
  • A label embedded in epoxy is placed on the cylinder to mark that it passed requalification (per § 180.213(c)).
  • During the requalification period, the label embedded in epoxy falls off due to corrosion on the cylinder and because the surface was not properly prepared prior to being marked.

As detailed in your request, § 180.213(c) authorizes a variety of marking methods following the successful requalification of a cylinder. These methods include applying a label embedded in epoxy that will remain legible and durable throughout the life of the cylinder. If the label does not meet this condition because it falls off during the requalification period, it is the opinion of this Office that the label may be replaced if the original requalifier can verify and ensure that the specific cylinder in question successfully passed requalification. One method of verification would be to match the manufacturer and serial number on the cylinder to the manufacturer and serial number in the requalification test records for the most recent test. If unable to be verified, the cylinder will need to pass the appropriate requalification tests. A new label embedded in epoxy or other marking method that meets the requirements of § 180.213(c) will need to be applied.

Please note that if a cylinder shows evidence of dents, corrosion, cracked or abraded areas, leakage, thermal damage, or any other condition that might render it unsafe for use in transportation, it must be tested and inspected without regard to any other periodic requalification in accordance with § 180.205(d). Furthermore, as detailed in § 180.205(f)(1), when a cylinder is pressure tested, the visual inspection must be performed in accordance with the appropriate CGA pamphlet, including inspection of any corrosion.

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


Dirk Der Kinderen
Chief, Standards Development
Standards and Rulemaking Division

180.213(c), 180.205(d), 180.205(f)(1)

Regulation Sections

Section Subject
180.205 General requirements for requalification of specification cylinders
180.213 Requalification markings