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Interpretation Response #14-0081 ([Atotech USA Inc.] [Ms. Patricia Siefferman])

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

Interpretation Response Details

Response Publish Date:

Company Name: Atotech USA Inc.

Individual Name: Ms. Patricia Siefferman

Location State: SC Country: US

View the Interpretation Document

Response text:

August 11, 2014

Patricia Siefferman, Ph.D.
Product Safety Specialist
Atotech USA Inc.
Americas Headquarters
1750 Overview Drive
Rock Hill, SC 29730

Ref. No. 14-0081

Dear Dr. Siefferman:

This responds to your April 2, 2014 request for clarification on the classification of corrosive and toxic materials under the Hazardous Materials Regulations (HMR; 49 CFR parts 171-180). Specifically, you seek clarification on the applicable classification of a chromium trioxide mixture with up to 50% chromium trioxide.

You indicate that testing of the material shows that it has an oral or dermal toxicity that meets the definition of a Division 6.1 (toxic) material specified in § 173.132. You state that conversations with PHMSA representatives affirmed that mixtures with a high chrome content may be classified as "Chromic acid solution, 8 (6.1), UN1755" or "Corrosive liquid, toxic, n.o.s., (chromium trioxide), 8 (6.1), UN 2922." You also indicate that you seek to harmonize with the European Agreement Concerning the International Carriage of Dangerous Goods by Road (ADR).

The HMR authorizes the proper shipping description of "UN 1755, Chromic acid solution, 8," not "UN 1755, Chromic acid solution, 8 (6.1)." In accordance with § 173.22, it is the shipper's responsibility to properly class and describe a hazardous material. This Office does not generally perform that function. However, you indicate that you seek to harmonize with the ADR. The listing in the 2013 edition of the ADR for "UN 1755, Chromic acid solution, 8, PGII" describes the material as aqueous solution, with not more than 30% chromic acid and does not include the subsidiary Division 6.1 risk. Therefore, provided your material meets the definitions for corrosive (see § 173.136) and toxic (see § 173.132) materials, it is our opinion that "UN2922, Corrosive liquid, toxic, n.o.s. (chromium trioxide), 8 (6.1), PGII", is the most appropriate description for your material and will not conflict with the ADR.

I hope this answers your inquiry. If you need additional assistance, please contact this office at 202-366-8553.


Robert Benedict
Chief, Standards Development Branch
Standards and Rulemaking Division

173.132, 173.22, 173.136

Regulation Sections

Section Subject
173.132 Class 6, Division 6.1-Definitions
173.136 Class 8-Definitions
173.22 Shipper's responsibility