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Interpretation Response #17-0021 ([Phase Four, Inc.] [Mr. Daniel Nash])

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

Interpretation Response Details

Response Publish Date:

Company Name: Phase Four, Inc.

Individual Name: Mr. Daniel Nash

Location State: CA Country: US

View the Interpretation Document

Response text:

June 29, 2017

Mr. Daniel Nash
Phase Four, Inc.
133 Center Street
El Segundo, CA 90245

Reference No. 17-0021

Dear Mr. Nash:

This letter is in response to your February 17, 2017, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to limited quantities of compressed gases. Specifically, you ask about the definition of a "container" as it applies to the exception from labeling and specification packagings as outlined in § 173.306(a)(1).

You state that you are shipping a compressed gas (UN2036, Xenon, compressed, 2.2) in what you describe as a pressurized system that is comprised of multiple pressurized vessels that are not isolated from each other, but collectively have a capacity less than 4 fluid ounces. You note that while in transportation the pressure vessels that contain the hazardous material and the manifold will be pressurized as a single volume (i.e., with no shut-off valve between the individual pressure vessels). You ask for confirmation of your understanding that the pressurized system can be considered a "container" for the purposes of § 173.306(a)(1) and thus excepted from labeling and specification packaging.

Your understanding is correct. The HMR do not specifically define the word "container." However, a standard dictionary defines it as, "one that contains [,] such as a receptacle (as a box or a jar) holding goods." "Container" as it is used in § 173.306(a)(1) includes all container types (except cigarette lighters), such as the pressurized system you describe, that comply with the requirements in § 173.306. Because the combined capacity of the two vessels in your system (i.e., the "container") is below the 4-fluid ounce capacity limitation outlined § 173.306(a)(1), you may use the limited quantity exception for compressed gases. Note that if the package is shipped by air, the exceptions from packaging and labeling do not apply.

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

173.306(a)(1), 173.306

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
173.306 Limited quantities of compressed gases