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Interpretation Response #05-0142 ([The AN Group] [Mr. Robert J. Fersterheim])

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

Interpretation Response Details

Response Publish Date:

Company Name: The AN Group

Individual Name: Mr. Robert J. Fersterheim

Location State: DC Country: US

View the Interpretation Document

Response text:

Dec 7,2005


Mr. Robert J. Fersterheim                     Reference No. 05-0142
Executive Director
The AN Group
1250 Connecticut Avenue, N.W
Suite 700
Washington, DC 20036

Dear Mr. Fersterheim:

This responds to your June 1, 2005 letter and subsequent conversations with Ben Supko of my staff requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you request that Acrylonitrile, stabilized, UN1093, PG I be reclassified as a PG II material because it has a flashpoint of approximately 1° C and a boiling point of approximately 77° C, which is consistent with that of a PG II flammable liquid.

A material with a flashpoint of approximately 1° C and a boiling point of approximately 77° C, that meets no other hazard, is best classified as a flammable liquid in Packing Group II However, acrylonitrile also exhibits the subsidiary hazard of Packing Group I poison. In accordance with the precedence of hazard table in § 173.2a(b), a material that meets Class 3, PG II and Division 6.1, PG I is assigned to Class 3. Note 1 following the precedence of hazard table states that the most stringent packing group assigned to a hazard of the material takes precedence over other packing groups. Therefore, a material meeting Class 3 PG II and Division 6.1 PG I is classified as Class 3 PG I.

I hope this information is helpful. Please contact us if you require additional assistance.



John A. Gale
Chief, Regulations Development
Office of Hazardous Materials Standards

172.101, 173.121

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.121 Class 3-Assignment of packing group