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Interpretation Response #13-0156 ([Matthews Associates, Inc] [Mr. George Foucher])

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

Interpretation Response Details

Response Publish Date:

Company Name: Matthews Associates, Inc

Individual Name: Mr. George Foucher

Location State: FL Country: US

View the Interpretation Document

Response text:

September 6, 2013

Mr. George Foucher
Vice President Quality Assurance
Matthews Associates, Inc.
220 Power Court
Sanford, FL 32771

Ref. No.: 13-0156

Dear Mr. Foucher:

This is in response to your email dated July 26, 2013, concerning requirements under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) for testing of lithium ion batteries. The specific requirements you address are contained in Section 38.3 of the United Nations (UN) Manual of Tests and Criteria and are implemented through the provisions of § 173.185.  Specifically you ask whether a failure of a test chamber to maintain the conditions specified in the test procedure constitute a “no test” or an “under test” and what actions are required.

The UN Manual of Test and Criteria describe procedures for conducting a series of tests designed to simulate certain transport and abuse conditions.  Test T.1 (Altitude Simulation) simulates air transport under low-pressure conditions.  The procedure requires test cells and batteries to be stored at a pressure of 11.6 kPa or less for at least six hours at ambient temperature (20 ± 5 °C).  In your letter, you stated that while performing an annual calibration of the altitude chamber, it was determined that the pressure sensor had a 3% error and the pressure during tests reached 11.95 kPa during the 6 hour test.  This increased pressure was not constant during the entire 6 hour test rather it was the maximum observed pressure during the test.

The procedure for the altitude simulation test requires the cells or batteries to be stored at a pressure of 11.6 kPa or less for 6 hours.  The test procedure permits lower pressures, but not higher pressures.  Results from tests conducted on cells at a higher than permitted pressures are not valid.  To compensate for a known percentage error in the test sensor, you may consider subjecting cells and batteries to a lower pressure or conducting more frequent calibration of test equipment to ensure accuracy.    

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


Delmer Billings
Senior Regulatory Advisor
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.185 Lithium cells and batteries