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Interpretation Response #02-0162 ([Johnson Matthey, Inc.] [Bill Erickson])

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

Interpretation Response Details

Response Publish Date:

Company Name: Johnson Matthey, Inc.

Individual Name: Bill Erickson

Location State: PA Country: US

View the Interpretation Document

Response text:

Jul 31, 2002

Mr. Bill Erickson                 Reference No. 02-0162
Operations Manager
Johnson Matthey, Inc.
1397 King Road
West Chester, PA 19380

Dear Mr. Erickson:

This is in response to your letter dated May 24, 2002, requesting clarification regarding the selection of a proper shipping name under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you asked whether your nickel catalyst material can be classified as “Self-heating solid, inorganic, n.o.s., 4.2, UN3190.

For a material not specifically identified by name in the Hazardous Material Table (HMT), the HMR requires that the material be described by the shipping name that "most appropriately describe" the material. in some cases, more than one shipping name could "most appropriately describe a material." Under § 173.22, it is the shipper's responsibility to properly classify and describe a hazardous material.  This office generally does not perform this function.  However, we provide assistance when we have the information available.

In your letter, you stated that the third party laboratory testing performed on the material was inconclusive due to the temperature of the test sample climbing rapidly from ambient to over 300º C within the first three minutes.  You further stated that the temperature continued to climb to over 400º C within 10 minutes, where it remained for approximately 30 minutes before dropping back down to ambient temperature two hours after the start of the test.

In the HMR, § 173.124(b) defines a Division 4.2 (Spontaneously Combustible) as being one of the following:

  1. A pyrophoric material.  A pyrophoric material is a liquid or solid that, even in small quantities and without an external ignition source, can ignite with five (5) minutes after coming in contact with air when tested according to UN Manual of Test and Criteria.
  2. A self-heating material.  A self-heating material is a material that, when in contact with air and without an energy supply, is liable to self-heat.  A material of this type which exhibits spontaneous ignition or if the temperature of the sample exceeds 200º C (392º F) during the 24-hour test period when tested in accordance with the UN Manual of Tests and Criteria, is classed as a Division 4.2 material.

Therefore, based on the information you provided, in addition to the fact that your material is heating up to a temperature of over 300º C within the first three minutes upon contact with air, it is the opinion of this office that the proper shipping name "Pyrophoric solid, inorganic, n.o.s., 4.2, UN3200" most appropriately describes your nickel catalyst material.

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
173.22 Shipper's responsibility