Radiation Safety


  • A current inventory of all radionuclides must be maintained at all times and available for RSS review.
  • All radioactive materials must be secured from unauthorized use or removal at all times; secure stock solutions of radioactive material or sealed/plated sources in a locked storage area and/or laboratory room when left unattended. Stock solutions of radioactive materials, sealed/plated sources, and radioactive wastes must never be stored in an unrestricted and non-posted area or facility.
  • All personnel must wear a laboratory coat, disposable gloves, and/or other approved safety apparel when handling unsealed radioactive material or contaminated objects. Eye protection should also be worn.
  • Designated radionuclide work and storage areas must be clearly identified and all equipment or containers used for radionuclide work must be labeled properly with radioactive material warning tape. Refrigerators and freezers used to store radionuclides must be clearly labeled with specific labels provided by RSS.

    NOTE: Radioactive material samples, stock vials, sealed & plated sources must be labeled with sufficient radiological information to identify the radionuclide, activity, and date.

  • Contamination surveys must be performed routinely by laboratory personnel working with unsealed forms (liquids or powders) of radioactive material in accordance with the U-M Contamination Survey Program. Documentation of contamination surveys must be maintained and available for RSS laboratory reviews or NRC inspections at all times. Contact RSS for a copy of the Contamination Survey Program brochure.
  • Appropriate shielding must be used for gamma, neutron, and high-energy beta emitting radionuclide work: low-density material such as Plexiglass or wood for beta emitters, high-density material such as lead for gamma emitters or x-rays, and hydrogenous material (water, paraffin, masonite) for neutron emitters.
  • Radiation survey meters used to detect radioactive contamination or verify shielding effectiveness should be checked for consistency on a regular basis using a small radioactive check source. Survey meters used to measure radiation exposure rates must be calibrated at least annually to a known radiation field.
  • Appropriate radiation monitoring dosimeters must be worn by individuals working with specified activities of gamma, neutron, high-energy beta emitting radionuclides and/or x-ray producing devices. Personnel dosimeters are not required for low- to medium-energy beta emitting radionuclides (H-3, C-14, P-33, S-35, or Ca-45). Contact RSS to obtain dosimeters.
  • All individuals handling radioactive material must maintain personal radiation exposures as low as is reasonably achievable (ALARA).
  • Volatile radionuclide work must be performed in an exhaust hood. Exhaust hoods should have an average face velocity of approximately 100 fpm at the working sash height.
    • Only non-volatile or low-activity (< 500 uCi) radionuclide work may be performed in biological cabinets which exhaust back into a laboratory room.
    • DO NOT use product protection hoods for radionuclide work due to the horizontal flow pattern in such hoods.
  • Radioiodinations must be performed in an exhaust hood specifically approved for radioiodinations by RSS and using an approved closed system procedure. In addition, each iodinator must have his/her first hot run observed and approved by a RSS health physicist. Refer to the U-M Iodination Safety Protocol brochure.