Paragraph 5.3.1 Gaseous diffusion barriers
(a)
Especially designed or prepared thin, porous filters, with a pore size of 100-1,000 Å (angstroms), a thickness of 5 mm (0.2 in) or less, and for tubular forms, a diameter of 25 mm (1 in) or less, made of metallic, polymer or ceramic materials resistant to corrosion by UF6 ...
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