PHMSA Response Letter

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Mr. Tom Magennis
Packaging Engineering
Hamilton Sundstrand
1 Hamilton Road
MS 2A-CC50
Windsor Locks, CT 06096

Reference No. 08-0042

Dear Mr. Magennis:

This is in response to your telephone conversations with Mr. Brian Moore, of the Pipeline and Hazardous Material Safety Administration’s Office of Hazardous Materials Technology, and our February 26 telephone conversation, concerning the applicability of this Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to a Refrigerating machine intended for use aboard an aircraft. The Refrigerating machine is fitted with a non-DOT specification cylinder containing about 10 pounds of 1,1,1,1 Tetrafluoroethane (Refrigerant gas R134a), a Division 2.2 (non-flammable gas) material, and is the subject of DOT-SP 14393.

Section 173.307, at paragraph (a)(4), provides that refrigerating machines containing 12 kg (25 pounds) or less of a non-flammable, non-toxic gas are not subject to the requirements of the HMR. Your company’s refrigerating machines qualify under this provision. Therefore, a special permit is not necessary.

I hope this satisfies your request. If you have any further questions, please contact this office at (202) 366-8553.

Sincerely,

Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards

cc: Mr. John A. Andrea
Product Line Manager
Hamilton Sundstrand Corporation

173.307