Update on Packaging for Uranium Hexafluoride Transport

The slightly enriched product, Uranium Hexafluoride (UF6), shipped from the enriching plants for the world's nuclear power plants, must be protected in order to conform to domestic and international transport regulations. The principal overpack currently in use is the U.S. Department of Transportation (USDOT) Specification 21PF-l, which protects Model 30 UF6 cylinders (Title 49, Code of Federal Regulations; Part 178 .121, Specification 21PF-l fire and shock resistant, phenolic - foam insulated overpack [horizontal loading]). Operational problems have developed due to both design and lack of maintenance, resulting in the entry of water into the insulation zone. Following major review of these problems, particularly those concerned with water entry and general deterioration, the design was re-examined and modified. A composite proposal for modification and supporting documentation is described in the Proposal for Modification to USDOT 21PF-l Fire and Shock Resistant Phenolic Foam - Insulated Overpacks, C. R. Barlow, et. al . , Martin Marietta Energy Systems, Inc., 1986. The proposal was submitted to USDOT by the U.S. Department of Energy (USDOE) as a petition to revise the DOT Specification for the 21PF-1. The petition was generally accepted by the USDOT, and the design changes and a final rule were published in the Federal Register on September 20, 1988 .