Sandia National Laboratories, New Mexico — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation Pipeline and Hazardous Materials Safety Administration 1200 New Jersey Avenue, SE Washington, D.C. 20590 APR 0 s 2312 Mr. David Castillo Sandia National Laboratories, New Mexico Regulated Waste and Pollution Prevention Department, 04144 P.O. Box 5800, MS1112 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, d1y 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. Sincerely, T. Glenn Foster Chief, Regulatory Review and Reinvention Branch Standards and Rulemaking Division#

Page 2From: Castillo, Dave H [mailto:DHCASTI@sandia.gov] Sent: Tuesday, February 21, 2012 5:17PM To: Lawson, Eleanor (PHMSA) Cc: Schade, A Carl; Krauss, Maryann; Tetreault, Kenneth J Subject: Interpretation Importance: High Eleanor, Per our phone discussion today, I have the following question: If the manufacture's documentation for the chemicai1-Hydroxybenzotriazole hydrate indicates it contains 14% water by mass, which of the two Proper Shipping Name entries in the November 1, 2011 Hazardous Materials Table applies: 1-Hydroxybenzotriazole, anhydrous, dry or wetted with less than 20% water by mass, (UN0508) or 1-Hydroxybenzotriazole, monohydrate (UN3474)? It should be noted that the stoichiometric calculation of water contained in 1-Hydroxybenzotriazole, monohydrate is 13.3% by mass. Therefore, it is not clear if the hydrate/monohydrate forms should be regarded as the anhydrous form when the total water is below 20%. Please let me know if you need any other information. Thanks. David Castillo Sandia National Laboratories, New Mexico Regulated Waste and Pollution Prevention Department, 04144 P.O. Box 5800, MS1112 Albuquerque, NM 87185-1112 Office (505) 284-4192 Cell (505) 269-1705 Pager(505)951-6340 Fax(505)284-4034#