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Interpretation Response #13-0012 ([Amex Int'l, Inc.] [Mr. Arlee Mueller])

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

Interpretation Response Details

Response Publish Date:

Company Name: Amex Int'l, Inc.

Individual Name: Mr. Arlee Mueller

Location State: MN Country: US

View the Interpretation Document

Response text:

February 14, 2013




Mr. Arlee Mueller
Amex Int'l, Inc.
1030 Lone Oak Road, Suite 130
Eagan, MN 55121

Ref. No.: 13-0012

Dear Mr. Mueller:

This responds to your January 8, 2013 letter concerning the transportation by vessel of accumulators installed in assembled machinery.  Specifically, you ask whether the International Maritime Dangerous Goods (IMDG) Code provides an exception similar to that which is found in § 173.306(f)(1) of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

Section 173.306(f)(1) specifies that accumulators which are installed in motor vehicles, construction equipment, and assembled machinery and designed and fabricated with a burst pressure of not less than five times their charged pressure at 70 °F, when shipped, are not subject to the requirements of the HMR.

The IMDG Code does provide a similar exception for accumulators under Special Provision 283 in paragraph 3.3.1.  Special Provision 283 specifies that articles containing gas, intended to function as shock absorbers, including impact-energy-absorbing devices or pneumatic springs, are not subject to the provisions of the IMDG Code provided: (1) each article has a gas space capacity not exceeding 1.6L and a charge pressure not exceeding 280 bar where the product of the capacity (liters) and charge pressure (bar) does not exceed 80; (2) each article has a minimum burst pressure of 4 times the charge pressure at 20 °C for products not exceeding 0.5L gas space capacity and 5 times charge pressure for products greater than 0.5L gas space capacity; (3) each article is manufactured from material which will not fragment upon rupture; (4) each article is manufactured in accordance with a quality-assurance standard acceptable to the competent authority; and (5) the design type has been subjected to a fire test demonstrating that pressure in the article is relieved by means of a fire-degradable seal or other pressure relief device, such that the article will not fragment and that the article does not rocket.  While Special Provision 283 in the IMDG Code is not identical to the exception provided in 173.306(f)(1) of the HMR, it does provide a similar exception for accumulators.

I hope this satisfies your inquiry.  Please contact us if we can be of further assistance.


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


Regulation Sections

Section Subject
173.306 Limited quantities of compressed gases