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Interpretation Response #12-0058 ([Sandia National Laboratories, New Mexico] [Mr. David Castillo])

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

Interpretation Response Details

Response Publish Date:

Company Name: Sandia National Laboratories, New Mexico

Individual Name: Mr. David Castillo

Location State: MS Country: US

View the Interpretation Document

Response text:

April 5, 2012



Mr. David Castillo
Sandia National Laboratories, New Mexico
P.O. Box 5800
Mail Stop 1117
Albuquerque, NM 87185-1117

Reference No.: 12-0058

Dear Mr. Castillo:

This responds to your February 21, 2012 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to proper shipping names. Specifically, you note that a manufacturer"s documentation for the chemical 1-Hydroxybenzotriazole hydrate indicates it contains 14% water by mass. You add that the stoichiometric calculation of water contained in the 1-Hydroxybenzotriazole, monohydrate is 13.3% by mass. You ask which of the two Proper Shipping Name entries in the HMR table apples: UN0508, 1-Hyrdroxybenzotriazole, anhydrous, dry or wetted with less than 20% water by mass, or UN3474, 1-Hydroxybenzotriazole, monohydrate?

Under § 173.22, it is the shipper's responsibility to classify a hazardous material. This Office does not normally perform this function. However, because the 1-Hydroxybenotriazole hydrate contains less than 20% water by mass, it is the opinion of this Office that UN0508, 1-Hydroxybenzotrizole, anhydrous, dry or wetted with less than 20% water by mass, would be the proper shipping name.

I hope this satisfies your inquiry. Please contact us if we can be of further assistance.



T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.22 Shipper's responsibility