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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 #14-0225 ([Dangerous Goods Advisory Council] [Mr. Delmer Billings])

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

Interpretation Response Details

Response Publish Date:

Company Name: Dangerous Goods Advisory Council

Individual Name: Mr. Delmer Billings

Location State: MD Country: US

View the Interpretation Document

Response text:

May 15, 2015

Mr. Delmer Billings
Technical Director
Dangerous Goods Advisory Council
7501 Greenway Center Drive, Suite 760
Greenbelt, MD  20770

Reference No. 14-0225

Dear Mr. Billings:

This is in response to your recent e-mail requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to secondary means of closure on inner packagings that contain Packing Group (PG) II and III liquid materials.  We have paraphrased your questions and answered them in the order you provided.  

Q1. What does the language “when a secondary means of closure cannot be applied or is impracticable to apply” as referenced in § 173.27(d)(2) mean?

A1. This language means an inner packaging intended for the transportation of Packing Group (PG) II and/or III liquids is designed in a manner that either does not permit or is impractical to permit its closure to be held securely in place by a separate “positive” (i.e., non-friction) means.  This language permits an alternative form of containment to be used if the secondary closure requirement in § 173.27(d), introductory paragraph, for an inner packaging of liquids placed in a combination packaging and transported by aircraft cannot be met.  

Q2. Do the following methods of closure satisfy the requirement for a secondary means of closure under § 173.27(d)(2):  adhesive tape, friction sleeves, welding or soldering, locking wires, locking rings, induction heat seals, and child-resistant closures?

A2. As stated in the introductory paragraph of § 173.27(d)(2), acceptable methods of secondary means of closure include the methods you listed as well as others of similar positive means, such as shrink wrap, to ensure closures are held in place.  Please note downward pressure alone exerted upon a friction-type closure (e.g., stoppers, corks, caps) does not satisfy this requirement.  

Q3. What factors determine if a secondary means of closure cannot be applied or is impracticable to apply?

A3. Packaging conditions that may make a secondary means of closure impracticable or impossible to apply include physical dimensions and/or conditions that may make containment or adherence in a secondary closure problematic.  These conditions can include irregular shaped or oversized packagings; packaging materials, condensation, or temperatures that make attachment with an adhesive difficult; and transportation conditions that promote expansion or contraction of the packagings or their contents.

Q4. If a method of closure is impracticable or cannot be applied, what support is necessary to make this determination?

A4. Unless otherwise excepted under the HMR, the package must be able to physically demonstrate that it satisfies the general packaging requirements prescribed in §§ 173.24, 173.24a, and 173.24b.  If the package also meets a DOT specification or UN standard, it must also satisfy the applicable performance requirements for these packagings, which is essentially a package engineering assessment.  Support for making a determination that a method of closure is impracticable or cannot be applied can occur through handling experience, package testing, incident reporting, and in discussions with PHMSA’s packaging engineers.  

I hope this satisfies your request.


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

173.27(d)(2), 173.27(d), 173.24, 173.24a, 173.24b

Regulation Sections

Section Subject
173.24 General requirements for packagings and packages
173.24a Additional general requirements for non-bulk packagings and packages
173.24b Additional general requirements for bulk packagings
173.27 General requirements for transportation by aircraft
173.27 General requirements for transportation by aircraft