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Interpretation Response #05-0121 ([Covington & Burling] [Mr. Zachary G. Parks])

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

Interpretation Response Details

Response Publish Date:

Company Name: Covington & Burling

Individual Name: Mr. Zachary G. Parks

Location State: DC Country: US

View the Interpretation Document

Response text:

Jul 6, 2005


Mr. Zachary G. Parks                      Reference No. 05-0121
Covington & Burling
1201 Pennsylvania Avenue, NW
Washington, DC 20004-2401

Dear Mr. Parks:

This responds to your letter dated May 19, 2005, requesting clarification of the classification procedures for aerosols under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether an aerosol that does not meet the definition of a Division 2.1 or 2.3 material, or any other hazard class, and does not exert in the packaging an absolute pressure of 280 kPa (40.6 psia) or greater at 20 °C (68 °F), should be classed as a Division 2.2 material.

The answer is no. If a material does not meet the definition of a hazard class or division, and is not a hazardous substance or hazardous waste, it is not regulated under the HMR. See § 173.115(b)

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



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.306 Limited quantities of compressed gases