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Interpretation Response #01-0208 ([MMA] [Mr. Winiam J. Schuchman])

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

Interpretation Response Details

Response Publish Date:

Company Name: MMA

Individual Name: Mr. Winiam J. Schuchman

Location State: MO Country: US

View the Interpretation Document

Response text:

October 11, 2001


Mr. Winiam J. Schuchman                   Reference  No. 01-0208
Executive Director
10733 Big Bend Blvd.
St. Louis, MO 63122-6027

Dear Mr, Schuchman:

T'his is in response to your July 30, 2001 letter and subsequent conversations with Michael Johnsen of my staff concerning the determination of the packing group for a flammable liquid under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you asked for clarification of the criteria for inclusion of viscous Class 3 materials in Packing Group III provided in the table in § 173.121 (b)(1)(iv) for viscous materials with a flash point under 23 degrees C (73 degrees F).

Your example involves a viscous material that has a flow time of about 90 seconds through a 4 mm diameter jet and has a flash poit of 7O degrees F.  To determine if a material could be considered a Packing Group III material, the conditions in § 173.121 (b)(1)(i) - (iv) must be met.  Your question concerns interpreting the table in § 173.121(b)(1)(iv). You would first identify your flow time in column one through a jet diameter indicated in column two.  Column three indicates the minimum flashpoint for your material to be considered a Packing Group III material.  A material, with a flow time of 90 seconds through a 4 mm diameter jet, falls between the range in the second entry and requires a flash point above 10 degrees C (50 degrees F) to qualify for a Packing Group III material.  Since the material in this example has a flash point of 70 degrees F, then it is considered a Packing Group III material if, in addition, the material also meets all other requirements of § 173.121 (b)(1).

I hope this satisfies your request.



Delmer F. Billings
Chief, Standards Development


Regulation Sections

Section Subject
173.121 Class 3-Assignment of packing group