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Interpretation Response #01-0178 ([W. R. Grace Co.-Conn] [Mr. Michael P. DeCicco])

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

Interpretation Response Details

Response Publish Date:

Company Name: W. R. Grace Co.-Conn

Individual Name: Mr. Michael P. DeCicco

Location State: MD Country: US

View the Interpretation Document

Response text:

OCT 22, 2001


Mr. Michael P. DeCicco                       Ref No. 01-0178

Polyolefin Catalyst Research
    and Development
W. R. Grace Co.-Conn
7500 Grace Drive
Columbia, Maryland 21044-4098

Dear Mr. DeCicco:

This responds to your letter dated July 13,2001, regarding classification of two products that were tested according to the UN Manual of Tests and Criteria as prescribed in § 173.124 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

Tests were performed by an outside laboratory which issued a report stating that one product, when shipped in containers of less than 3000L, does not meet the criteria for a Division 4.2 material. The testing laboratory concluded that a second product does not meet the criteria for a Division 4.3 material. You state that these products meet Division 4.1 (flammable solid) criteria, but disagree with the laboratory's test conclusions. You are of the opinion that these products should more appropriately be classed as Division 4.2 (spontaneously combustible) and Division 4.3 (dangerous when wet), respectively.

This Office recognizes the "UN Manual of Tests and Criteria," prescribed in the definitions for Division 4.2, and 4.3 hazards in § 173.124, as the standard for determining the appropriate classifications in the Class 4 hazard class. Tests in § 173.124 are intended to be carried out under ambient conditions. Therefore, you may rely on the laboratory's tests results to classify your products as only meeting the Division 4.1 criteria. However, if additional information indicates your products react in a unique way to pose Division 4.2 or Division 4.3 hazards, you may take the worst case scenario to classify them as Division 4.2 or Division 4.3, in addition to Division 4.1.

I hope this satisfies your inquiry. If we can be of further assistance, please contact us.



Delmer F. Billings
Chief, Standards Development
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.124 Class 4, Divisions 4.1, 4.2 and 4.3-Definitions