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Interpretation Response #08-0185 ([EHS Associates, Inc.] [Mr. Daniel J. Young])

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

Interpretation Response Details

Response Publish Date:

Company Name: EHS Associates, Inc.

Individual Name: Mr. Daniel J. Young

Location State: NC Country: US

View the Interpretation Document

Response text:

December 23, 2008



Mr. Daniel J. Young


EHS Associates, Inc.

3301 Bentwillow Drive

Fuquay-Varina, NC 27526

Ref. No. 08-0185

Dear Mr. Young:

This responds to your letter regarding the approval of explosives under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether your client"s product (surge arresters) containing a small amount (2.8 grams) of a Division 5.1, Packing Group II hazardous material (potassium chlorate), is excepted from the explosive approval process prescribed in § 173.56. Additionally, it is your understanding that the negligible risk posed by your client"s product in transportation should except it from the HMR under the conditions described in your letter.

Under §173.56(i) of the HMR, the Associate Administrator for Hazardous Materials Safety may specify a classification or except an explosive material from the requirements of the HMR. We agree with your client"s assessment that because there is no explosion when the surge arrester is activated, and the surge arrester can only be activated by a high-level of predetermined electric current, the product is not subject to the explosive approval and classification process under § 173.56. We find, however, that your client"s product would more appropriately be described as "Dangerous goods in apparatus, Class 9, UN3363," and packaged in accordance with § 173.222. Under Special provision 136 assigned to the entry "Dangerous goods in apparatus," in column 7 of the Hazardous Materials Table, the small quantity of potassium chlorate (2.8 grams) in each surge arrester qualifies for the small quantity exceptions found in § 173.4 and, when packaged in accordance with § 173.222, is excepted from the HMR.

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


Edward T. Mazzullo


Office of Hazardous Materials Standards

173.56(i), 173.222

Regulation Sections

Section Subject
173.222 Dangerous goods in equipment, machinery or apparatus
173.56 New explosives-definition and procedures for classification and approval