Storage and Disposal of Radioactive Radio Isotope Waste:
SCIENCE & RESEARCH REVIEW UPDATES.
Radioisotopes must be stored in lockable metal cabinets or refrigerators at designated locations within a laboratory. These controlled locations should be protected against unauthorized access. Proper storage of radioisotopes in the laboratory includes providing sufficient shielding to reduce emitted radiation level to the lowest possible (and certainly to below the legally prescribed limit of 1µSv/hr), and preventing the release or spillage of radioactive materials.
Storage of Radioactive Material:
All storage locations housing P-emitters should be checked with a gamma survey meter for the production of bremstrahlung radiation. To reduce such radiation, all O-emitters should not be stored in containers with high atomic numbers.
Once opened, all vials containing unbound sources (eg. radioiodine) should not be stored in refrigerators, etc., but in fume hoods and every effort made to keep these vessels tightly sealed.
Shielding should be arranged to avoid blocking rear exhaust slots or hood faces.
Storage locations for radioactive materials, such as refrigerators, should be labeled with the “Caution Radioactive Material” signs. Storage containers and waste containers should also be labeled with “Caution Radioactive Material” signs.
Disposal of Radioactive material:
All waste contaminated with radioisotopes must be disposed of as radioactive waste. In particular, solid waste should be packed in clear plastic bags. It should not contain pourable liquids or animal carcasses. Needles, pipettes and other sharp objects should be placed in a puncture-proof sharps container, to protect the waste handler and to prevent piercing the waste bag.
Radioactive waste with short half-lives may be stored and some liquid waste can be diluted until their activities drop below acceptable levels, and then disposed as normal waste. eg. very low levels of radioactive isotopes may be discharged into the sewer system.
Separate single monthly discharge limits are established for solid waste disposed as normal waste and liquid waste discharged into the sewer system to cover all operations for the entire campus. The exact quantities vary as a function of the specific isotopes involved. Before any such discharge of radioactive isotopes, the user must seek the permission of the RPO by providing the estimated quantity to be discharged per month. Records of all subsequent discharges must them be kept by the user.
Materials with non-dischargable levels of radioisotopes should be segregated according to isotope and form, and tagged with a Radioactive-waste label. Some may need to be stored on campus while others may need to be disposed by returning to the manufacturer or to the Radiation Board for long term storage at designated locations.
Note : The information for educating and knowledge improvement review purposes only, from the sources of Radiation ordinance, cap 303 Laws.
To be continued.