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Interpretation Response #21-0101

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

Interpretation Response Details

Response Publish Date:

Company Name: Hydro-Test Products, Inc.

Individual Name: Carlos Graca

Location State: MA Country: US

View the Interpretation Document

Response text:

January 19, 2022

Carlos Graca
Hydro-Test Products, Inc.
85 Hudson Road
Stow, MA  01775

Reference No. 21-0101

Dear Mr. Graca:

This letter is in response to your November 2, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to recordkeeping requirements for the visual inspection used to requalify cylinders. In your email, you note that § 180.209(g) allows for an external visual inspection to be performed in lieu of a periodic hydrostatic test and requires the results to be recorded and maintained in conformance with § 180.215. However, you note that the recordkeeping requirements include reference to more information than can be provided by an external visual inspection (e.g., actual test pressure).

We have paraphrased and answered your questions as follows:

Q1. You ask what information must be recorded for a visual inspection performed in accordance with § 180.209(g).

A1. A person who requalifies a cylinder using an external visual inspection only needs to provide information specified in § 180.215(b) relevant to an external visual inspection. Information such as expansion, test pressure, verification, or calibrated cylinder values do not need to be recorded as part of the recordkeeping requirements.

Q2. You ask whether the manufacturing date and gas service must be recorded during the external visual inspection.

A2. The answer is yes. See answer "A3" for Letter of Interpretation, Ref. No. 21-0100.

Q3. You note a seemingly circular reference among §§ 180.209(g), 180.215, CGA C-6, and CGA C 6.3, and ask for clarity on which regulations to follow when performing an external visual inspection of a cylinder.

A3. Section 180.209 provides requirements for the requalification of cylinders. Paragraph (g) provides conditions that allow for an external visual inspection requalification of a cylinder that is in specialized service. CGA C-6 and CGA C-6.3 are industry developed standards for the performance of a visual inspection and have been incorporated by reference into the HMR and thus—by definition—are made part of the HMR (see § 171.8) for the definition of incorporated by reference). Because of reliance on visual inspections as a means to requalify these cylinders, reference is made to these standards to ensure that visual inspections are performed properly and consistently by requalifiers. Finally, reference to § 180.215 provides a reminder of the requirements for reporting and recordkeeping of requalified cylinders. Thus, all are regulations that should be followed in accordance with § 180.209(g).

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


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

171.8, 180.215, 180.209, 180.209(g)

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
180.209 Requirements for requalification of specification cylinders
180.215 Reporting and record retention requirements