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Interpretation Response #19-0077

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

Interpretation Response Details

Response Publish Date:

Company Name: LANXESS Solutions, US, Inc.

Individual Name: Ernest Marcel

Location State: CT Country: US

View the Interpretation Document

Response text:

June 24, 2020

Ernest Marcel, CDGP, DGSA
LANXESS Solutions, US, Inc.
2 Armstrong Road
Shelton, CT, 06484

Reference No. 19-0077

Dear Mr. Marcel:

This letter is in response to your June 10, 2019, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to mixtures containing a hazardous material that is listed in the Hazardous Materials Table (HMT) with a "+" in Column (1) and assigned Special Provision (SP) 279 in the UN Model Regulations and the International Maritime Dangerous Goods (IMDG) Code. Specifically, you ask about the classification of a product containing less than 5% toluene diisocyanate.

We have paraphrased and answered your questions as follows:

Q1. You seek confirmation that SP 279 in the IMDG Code and the "+" sign in Column (1) of the HMT assigns the UN Number, Proper Shipping Name, Hazard Class, and Packing Group (PG) to shipments of UN2078, but not to products containing toluene diisocyanate.

A1. Your understanding is correct. Special Provision 279 and the "+" in Column (1) apply to the listed material, and do not extend to all mixtures or solutions that contain the material. It is the responsibility of the shipper to classify mixtures and solutions of toluene diisocyanate taking into account the classification criteria within the IMDG Code and the HMR.

Q2. You ask whether the UN Model Regulations and the IMDG Code classify "UN2078, Toluene Diisocyanate, Class 6.1, PG II" as a toxic-by-inhalation hazard (TIH) material.

A2. The answer is no. Neither the UN Model Regulations or the IMDG Code specifically identify UN2078 as a TIH material.

Q3. You ask whether a hazard classification under the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) takes precedence over the hazardous classification criteria of the various hazardous material transportation regulations (e.g., the HMR, IMDG Code, etc.).

A3. The answer is no. For purposes of transportation within the United States, the classification criteria in the HMR take precedence over other standards, unless expressly authorized for use. For example, § 171.22 provides authorization and conditions for the use of international standards and regulations.


Shane Kelley
Standards and Rulemaking Division
Office of Hazardous Material Standards


Regulation Sections

Section Subject
171.22 Authorization and conditions for the use of international standards and regulations