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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #13-0164 ([Mr. Cesar Enrico])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. Cesar Enrico

Country: US

View the Interpretation Document

Response text:

January 15, 2014

Mr. Cesar Enrico
Quality Manager
LAN Peru

Ref. No.: 13-0164

Dear Mr. Enrico:

This is in response to your email dated August 9, 2013, requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the filling and requalification of DOT specification cylinders. Your questions are paraphrased and answered as follows:

Q1.  Are DOT cylinders required to be requalified each time a cylinder is removed from an aircraft?

A1.  Each cylinder bearing a DOT specification marking must be requalified in accordance with the appropriate period specified in the requalification table in § 180.209(a).  A cylinder must be tested and inspected, without regard to any other periodic requalification requirements, prior to further use if: (1) The 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; (2) The cylinder has been in an accident and has been damaged to an extent that may adversely affect its lading retention capability; (3) The cylinder shows evidence of or is known to have been over-heated; or (4) The Associate Administrator determines that the cylinder may be in an unsafe condition (§ 180.205(d)).

Q2.  Is a DOT authorized person required to refill an oxygen cylinder each time it is removed from the aircraft?

A2.  Partially filled cylinders may continue to be transported.  The filling or re-filling of a DOT marked cylinder with oxygen must follow the requirements of §§ 173.301 and 173.302.

Q3.  Are cylinders required to be requalified only if the specified service life has expired or it is past its requalification date?

A3.  A cylinder with a specified service life may not be refilled and offered for transportation after its authorized service life has expired.  A cylinder past its requalification date may not be refilled and offered for transportation until it is requalified.  A cylinder must be requalified prior to further use without regard for the requalification period if the cylinder meets one or more of the conditions in § 180.205(d), (see A1.).

I hope this information is helpful.  If you have further questions, please do not hesitate to contact this office.


Duane Pfund
International Standards Coordinator
Standards and Rulemaking Division

173.301, 173.302 & 180.205

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
173.302 Filling of cylinders with nonliquefied (permanent) compressed gases or adsorbed gases
180.209 Requirements for requalification of specification cylinders