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Interpretation Response #05-0132 ([nanoCoolers] [Mr. Craig Johnston])

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

Interpretation Response Details

Response Publish Date:

Company Name: nanoCoolers

Individual Name: Mr. Craig Johnston

Location State: TX Country: US

View the Interpretation Document

Response text:

Jul 19, 2005


Mr. Craig Johnston                       Reference No. 05-0132
5307 Industrial Oaks Boulevard
Austin, TX 78735-8821

Dear Mr. Johnston:

This responds to your letter concerning the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 17 1-180) to your company’s product, a thermal transport system. You describe the thermal transport system as being comprised .of nickel and PVC based tubing, a plastic pump, and a nickel/copper block. The block allows heat transport material to flow through the block and pick up heat from a source component. All of the parts within the system are non-reactive with the heat transport material. The thermal transport material flows through a closed cooling loop that contains a source heat exchanger, an ambient heat exchanger, and piping to interconnect them. The thermal transport system contains not more than 10 mL of thermal transport material consisting of the following elements by weight: 50-76% Gallium, 0-25% Indium, 0-15% Tin, 0-4% each Zinc, Silver arid Bismuth, and less than 1% Copper. The entire system is sealed and the design is tested to ensure no release of fluid. You also submitted drawings of the system and test data.

Of the identified materials, only gallium is regulated as a hazardous material. Section 173.162(c) excepts manufactured articles and apparatuses, each containing not more than 100 mg (0.03 5 oz.) of gallium and packaged so that the quantity of gallium per package does not exceed 1 g (0.35 oz.) from the HMR. Your company’s thermal transport system exceeds the quantity of hazardous material allowed by § 173.162(c) and, therefore, is subject to the HMR.

You may wish to seek authorization to transport your company’s thermal transport system under the terms of an exemption by contacting the Pipeline and Hazardous Materials Safety Administration’s Office of Hazardous Materials Exemptions and Approvals (OHMEA). Exemptions are granted on a case-by-case basis to authorize relief from certain requirements under the HMR. Procedures for applying for an exemption are set forth in 49 CFR 107.105. The OHMEA may be reached at (202) 366-4512.

I trust this satisfies your inquiry.



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards
172.101 (P), 173.22

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.22 Shipper's responsibility