Nuclear Non-proliferation Import and Export Control Regulations — A.2.4
sion by UF 6 , including (a) feed autoclaves, ovens or systems used for passing UF 6 to the enrichment process; (b) desublimers (or cold traps) or pumps used to remove UF 6 from the enrichment process for subsequent transfer upon heating; (c) solidification or liquefaction stations used to remove UF 6 from the enrichment process by compressing and converting UF 6 to a liquid or solid form; and (d) product or tails stations used for transferring UF 6 into containers. A.2.4.4.2 Header piping systems Especially designed or prepared piping systems and header systems for handling UF 6 within the gaseous diffusion cascades. This piping network is normally of the double header system with each cell connected to each of the headers. A.2.4.4.3 Vacuum systems (a) especially designed or prepared vacuum manifolds, vacuum headers and vacuum pumps having a suction capacity of 5 m 3 /min or more; and (b) vacuum pumps especially designed for service in UF 6 -bearing atmospheres, made of or protected by materials resistant to corrosion by UF 6 . These pumps may be either rotary or positive, may have displacement and fluorocarbon seals and may have special working fluids present. A.2.4.4.4 Special shut-off and control valves Especially designed or prepared bellows-sealed valves, manual or automated, shut-off or control, made of or protected by materials resistant to corrosion by UF 6 , for installation in main and auxiliary systems of gaseous diffusion enrichment plants. A.2.4.4.5 UF 6 mass spectrometers with ion sources Especially designed or prepared mass spectrometers capable of taking on-line samples, from UF 6 gas streams and having all of the following characteristics: (a) the capability of measuring ions of 320 atomic mass units or greater with a resolution of better than 1 part in 320; (b) ion sources constructed of or protected by nickel, nickel-copper alloys with a nickel content of 60% by weight or more, or nickel-chrome alloys; (c) electron bombardment ionization sources; and (d) a collector system suitable for isotopic analysis. A.2.4.5 Especially designed or prepared systems, equipment and components for use in aerodynamic enrichment plants, including: A.2.4.5.1 Separation nozzles Especially designed or prepared separation nozzles and separation nozzle assemblies. The separation nozzles consist of slit-shaped, curved channels having a radius of curvature of less than 1 mm, resistant to corrosion by UF 6 and having a knife-edge within the nozzle that separates the gas flowing through the nozzle into two fractions. A.2.4.5.2 Vortex tubes Especially designed or prepared vortex tubes and vortex tube assemblies. The vortex tubes are cylindrical or tapered, made of or protected by materials resistant to corrosion by UF 6 , and with one or more tangential inlets. The tubes may be equipped with nozzle-type appendages at either or both ends. A.2.4.5.3 Compressors and gas blowers Especially designed or prepared compressors or gas blowers made of or protected by materials resistant to corrosion by the UF 6 carrier gas (hydrogen or helium) mixture. A.2.4.5.4 Rotary shaft seals Especially designed or prepared rotary shaft seals, with seal feed and seal exhaust connections, for sealing the shaft connecting the compressor rotor or the gas blower rotor with the driver motor so as to ensure a reliable seal against out-leakage of process gas or in-leakage of air or seal gas into the inner chamber of the compressor or gas blower which is filled with a UF 6 /carrier gas mixture. A.2.4.5.5 Heat exchangers for gas cooling Especially designed or prepared heat exchangers made of or protected by materials resistant to corrosion by UF 6 . A.2.4.5.6 Separation element housings Especially designed or prepared separation element housings, made of or protected by materials resistant to corrosion by UF 6 , for containing vortex tubes or separation nozzles. A.2.4.5.7 Feed systems/product and tails withdrawal systems Especially designed or prepared process system