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Interpretation Response #10-0253 ([AVOX Systems Inc.] [Mr. Joesph Contino])

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

Interpretation Response Details

Response Publish Date:

Company Name: AVOX Systems Inc.

Individual Name: Mr. Joesph Contino

Location State: PA Country: US

View the Interpretation Document

Response text:

December 22, 2010



Mr. Joesph Contino

AVOX Systems Inc.

225 Erie Street

Lancaster, PA 14086

Reference No.: 10-0253

Dear Mr. Contino:

This responds to your November 24, 2010 email regarding the requirements for the examination, testing and approval of Chemical Oxygen Generators under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Your questions are paraphrased and answered as follows:

Q1. Does the requirement to have chemical oxygen generators examined in accordance with § 173.56, include the rigid outer packaging specified in § 173.168(d)?

A1: The answer is no. In accordance with § 173.168(a), a "chemical oxygen generator that is shipped with an explosive or non-explosive means of initiation attached must be classed and approved by the Associate Administrator in accordance with the procedures specified in § 173.56 of this subchapter." The requirements in § 173.56 apply to the chemical oxygen generator itself; not the packaging referenced in § 173.168(d). In accordance with § 173.168(d), a chemical oxygen generator and a chemical oxygen generator installed in equipment, (e.g., a Protective Breathing Equipment), when transported by cargo-aircraft only, must be placed in a rigid outer packaging that is capable of successfully passing the Flame Penetration Resistance Test specified in Appendix E and the Thermal Resistance Test specified in Appendix D to part 178 of this subchapter. These tests are performance oriented tests and are independent of the examination of the chemical oxygen generator required by § 173.56.

Q2. If the rigid outer packaging does require this testing, does the testing have to be performed by a competent authority laboratory?

A2. The answer is no. The rigid outer packaging must be able to successfully pass the Flame Penetration Resistance Test specified in Appendix E and the Thermal Resistance Test specified in Appendix D to part 178 of this subchapter. However, there is no requirement for an approved laboratory to perform these tests.

Q3 If the answer to Q2 is yes: Are the various packaging providers which advertise, test, mark and certify their packagings as HM-224B compliant for chemical oxygen generators, without sending or referring the product and package to an approved lab, doing so in compliance or in violation on § 173.168?

A3. See A2.

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

173.168, 173.56

Regulation Sections

Section Subject
173.168 Chemical oxygen generators
173.56 New explosives-definition and procedures for classification and approval