Patent Number: 
Section: claims

1. A container for a radioactive fluid, the container comprising:a body having a hollow inner chamber for containing the radioactive fluid, the chamber including an inner surface and an opening, a portion of the inner surface having a smooth burnished surface;a cap removably couplable to the body for sealing the opening, the cap having a plug that is insertable into the chamber through the opening, wherein the plug includes a groove; andan O-ring disposed within the groove of the plug,wherein an outer edge of the O-ring seats against the smooth burnished surface when the plug is fully received within the opening of the chamber,and wherein the body and the cap are made of a material substantially comprising a radiation shielding material. 2. The container of claim 1, wherein the burnished surface comprises a tapered burnished surface. 3. The container of claim 1, wherein with the plug fully received within the opening of the chamber, the cap is manually removable from the body. 4. The container of claim 1, wherein with the plug fully received within the opening of the chamber, the cap remains coupled to the body when pressure inside the chamber is higher than pressure outside the container by 7-15 psi. 5. The container of claim 1, wherein the O-ring comprises a silicone rubber. 6. The container of claim 1, wherein the radiation shielding material includes lead. 7. The container of claim 6, wherein the radiation shielding material substantially comprises lead and antimony. 8. The container of claim 1, wherein with the plug fully received within the opening of the chamber, the cap remains coupled to the body when the container is subjected to a temperature in the range of −40° C. to 70° C. 9. The container of claim 1, wherein the cap includes a manually gripable outer rim. 10. The container of claim 1, wherein the groove comprises a circumferential groove. 11. The container of claim 1, wherein the radioactive fluid comprises a radioactive gas. 12. A method of manufacturing a container for a radioactive fluid, the method comprising:forming a body having a hollow inner chamber for containing the radioactive fluid, the chamber including an inner surface and an opening;burnishing at least a portion of the inner surface of the chamber to form a burnished portion of the inner surface;forming a cap that is removably coupleable to the body for sealing the opening, the cap having a plug that is insertable into the chamber through the opening, wherein the plug includes a groove;coupling an O-ring to the cap by inserting the O-ring into the groove on the plug; andinserting the plug into the opening of the chamber until the plug is fully received within the opening and the O-ring is seated against the burnished portion of the inner surface of the chamber to form a fluid tight seal,wherein the body and the cap are made of a material substantially comprising a radiation shielding material. 13. The method of claim 12, wherein the step of forming the body comprises casting the body. 14. The method of claim 12, wherein the step of forming the cap comprises casting the cap. 15. The method of claim 12, wherein the step of burnishing comprises:inserting a burnishing tool into the chamber through the opening such that at least a portion of the burnishing tool contacts the inner surface of the chamber; androtating the burnishing tool relative to the body. 16. The method of claim 15, wherein the burnishing tool comprises a tapered outer surface. 17. The method of claim 15, wherein the burnishing tool comprises S7 tool steel. 18. The method of claim 12, wherein the radiation shielding material includes lead. 19. The method of claim 18, wherein the radiation shielding material substantially comprises lead and antimony. 20. The method of claim 12, wherein with the plug fully sealed with the burnished surface, the cap remains coupled to the body when pressure inside the container is higher than pressure outside the container by 7-15 psi. 21. The method of claim 12, wherein the groove comprises a circumferential groove. 22. The method of claim 12, wherein the radioactive fluid comprises a radioactive gas. 23. The method of claim 12, wherein the burnished portion comprises a tapered burnished portion.