URS Corporation — Hazardous Materials Safety Interpretation

Page 1U.S. Department of Transportation 400 Seventh St., S.W. Washington, D.C. 20590 special Programs Research and Administration FEB 1Q 2005 Mr. Andrew N. Romach Ref No.: 04-0249 Corporate Regulatory Manager URS Corporation 1600 Perimeter Park Drive Morrisville, NC 27560 Dear Mr. Romach: This responds to your October 27, 2004 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) as applicable to jet engines. Specifically, you ask if jet engines may be classed as "Engines, internal combustion." In component referred to as a "spark gap." You indicate that the "spark gap" contains a addition, you state that the exciter box, an integral component of jet engines, contains a limited quantity of Krypton-85 gas, a radioactive material assigned to UN2910. You ask if a cleaned and purged jet engine and securely installed "spark gap" may be shipped as unregulated material in accordance with § 173.220(a)(1) and (d)(1), respectively. Aircraft engines, whether piston-powered, rotary-powered, or turbine-powered, derive their power by heat and pressure produced by the compression and combustion of a fuel-air mixture. Therefore, aircraft engines including jet engines are properly classified as "Engines, internal combustion, 9, UN3166." In accordance with § 173.220(a)(1), an engine that is completely drained, sufficiently cleaned of residue, and purged of vapors to remove any potential hazard and that will not release liquid fuel in any orientation is not subject to the HMR. In addition, a limited quantity of radioactive material that is contained in a securely installed engine component that is integral to the operation of the engine is excepted from the requirements of the HMR (see § 173.220(d)(1)). Therefore, a cleaned and purged jet engine with a "spark gap" contained in a securely installed exciter box is excepted from the requirements of the HMR, provided the applicable requirements in § 173.220 are met. I hope this information is helpful. Please contact us if you require additional assistance. Sincerely, Edward T. Mazzullo Director Office of Hazardous Materials Standards 173.220 040249#

Page 2Supko URS $173.220 October 27, 2004 Engines 04-0249 Mr. Ben Supko Office of Hazardous Material Standards Research and Special Programs Administration U.S. Department of Transportation 400 7th Street, SW (DHM-10) Washington, DC 20590-0001 FAX: (202) 366-3012 Dear Mr. Supko: Q-1 I am writing to you to request a written regulatory interpretation concerning whether an Jet engine would be considered an Internal Combustion Engine for the purposes of hazard classification and shipment under the DOT HAZMAT regulations. In the Hazardous Material Table (49 CFR 172.101), for the proper shipping name Engines, Internal Combustion, column (d) references 49 CFR 173.220. Paragraph (d)(1) integral components of the engine and necessary for the operation of the engine to be of 49 CFR 173:220 allows items of equipment containing hazardous materials, which are shipped as not subject to the DOT HAZMAT regulations, so long as these items are securely installed in the engine. Aircraft jet engines contain a spark gap. The spark gap, which separately is shipped as a item of equipment that is an integral component of any aircraft engine and necessary for radioactive material excepted package due to a very low amount of Krypton-85 gas, is an the operation of the engine. The spark gap is securely affixed inside an exciter box, which is securely installed in the engine. Q-2 Would we be able to ship a jet engine with a spark gap securely installed as DOT not restricted if the aircraft engine is cleaned and purged of all residual fuel and meets the requirements of 49 CFR. 173.220(a)(1): "An engine may be considered as not containing Tue! when the fuel tank, engine components, and fuel lines have been completely drained, sufficiently cleaned of residue, and purged of vapors to remove any potential hazard and the engine when held in any orientation will not release any liquid fuel." Thank you for your consideration of this request. Sincerely, Alize Andrew N. Romach Corporate Regulatory Manager URS Corporation JRS Corporatior Morrisville, NC 27560 600 Perimeter Park Drive Tel: 919.461.1220 Fax:919.461.1371#