Interpretation Response #12-0239
Below is the interpretation response detail and a list of regulations sections applicable to this response.
Interpretation Response Details
December 20, 2012
Mr. James McManus
7 Commerce Drive
Danbury, CT 06810
Ref. No.: 12-0239
Dear Mr. McManus:
This responds to your October 23, 2012 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the segregation of hazardous materials when transported by vessel. Your questions are paraphrased and answered below.
Q1: You ask if a Division 2.3 gas (with a subsidiary hazard of Division 2.1) and a Division 2.3 gas (with a subsidiary hazard of Class 8) require segregation?
A1: The answer is no, provided the Division 2.3 gases are shipped in accordance with the applicable provisions detailed in § 176.83. Multiple Division 2.3 gases may be stowed in the same container for vessel transportation without regard to the subsidiary hazards, provided the different poison gas materials are not capable of reacting dangerously with each other and causing any of the conditions listed below. Specifically, as provided in § 176.83(a)(8) and notwithstanding the requirements of paragraphs (a)(6) and (a)(7), hazardous materials of the same class may be stowed together without regard to segregation required by secondary hazards (subsidiary risk label(s)), provided the substances do not react dangerously with each other and cause: (1) a combustion and/or evolution of considerable heat; (2) an evolution of flammable, toxic or asphyxiant gases; (3) the formation of corrosive substances; or (4) the formation of unstable substances.
Q2: You ask if a Division 2.3 gas (with a subsidiary hazard of Division 2.1) and a Division 2.3 gas (with a subsidiary hazard of Class 8) can be stowed in the same transport unit when transported by vessel?
A2: The answer is yes, as provided in A1.
I trust 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