Radiation Safety


Disposal of Materials and Equipment

  1. Notify RSS prior to relocating, discarding, or junking x-ray units, liquid scintillation counters (LSC), or gamma counters. Liquid scintillation counters and gamma counters may contain a radioactive sealed source (Cs-137, Ba-133, or Ra-226) which must be removed by the manufacturer or RSS prior to disposition.
  2. Only OSEH is authorized to dispose of radioactive wastes at the U-M. Adhere to established protocols for the segregation, storage, and identification of radioactive wastes. All radioactive waste must be disposed in OSEH-approved waste containers.
  3. Radionuclide users are strongly encouraged NOT to generate mixed waste (radioactive & chemical combinations) at the U-M. Segregate radioactive wastes from hazardous chemicals whenever possible; DO NOT combine chemicals & radioactive wastes in the same container unless the combination is an inherent part of your experimental protocols. Isolate chemical and mixed wastes from all forms of radioactive wastes. Reduce the volumes of unavoidable mixed waste at all times. Contact the Hazardous Materials Management staff (3-4568) for guidance and recommendations.
  4. Contact RSS prior to servicing equipment that had been used for radioactive material work. The equipment must be surveyed and decontaminated, if applicable.
  5. Report all radioactive material spills and other incidents or accidents involving radioactive material or radiation-producing devices to Radiation Safety Service (764-6200) or the U-M Public Safety & Security Office [3-1131 or 911] as soon as possible after occurrence.

Proper Segregation and Disposal of Low-Level Radioactive Wastes at the University of Michigan

Labs / Facilities

When researchers vacate labs or other facilities or when they elect to permanently terminate use of radioactive materials, RSS must decommission those facilities prior to their return to unrestricted use. Please refer to the general OSEH Guideline on Decommissioning. It provides detailed instruction on lab decommissioning for radioactive materials, chemicals, biologicals, etc.

Radiological decommissioning includes a number of steps:

  • Notify RSS of your intent to vacate or terminate use of radioactive materials and identify the rooms or facilities affected. If you are moving or are subject to a deadline, provide a date by which the decommissioning must be complete.
  • Arrange for the disposal (contact HMM at 763-4568) or transfer (Contact RSS at 764-6200) of all radioactive materials that are located in the facilities to be decommissioned.
  • Conduct a screening survey to identify possible contamination. Clean up contamination. Call RSS if you need assistance with decontamination.
  • Contact RSS to arrange for a decommissioning survey. A representative from OSEH will perform a survey of the facilities involved and will advise you of any contamination identified. RSS can assist with decontamination if needed. The RSS rep will conduct a follow-up survey of all decontaminated areas.
  • Remove all labels, postings and markings that identify the presence of radioactive material. E.g. Tape and labels bearing the word "Radioactive", door postings, refrigerator postings, etc.


Users often need to relocate, service or dispose of equipment that was used with radioactive materials and that may be contaminated. Users that intend to relocate such equipment or to release it for: i) unrestricted use, ii) in-house or return service by the manufacturer, iii) in-house service by U-M personnel, or iv) for sale through Property Disposition must arrange to have RSS conduct a contamination survey of such equipment prior to release or relocation. Users must complete and attach a copy of the OSEH equipment decommissioning form certifying that the equipment is free of contaminants.

Sealed Sources

Some common devices and instruments contain radioactive sealed sources installed by the manufacturer. These sources are not intended to be opened but are used when using the device as part of its operation or to test the response of the instrument. Some common examples include gas chromatographs with Ni-63 electron capture detectors, liquid scintillation counters, gamma counters, static discharge devices and air ionization devices, certain self-luminous "EXIT" signs, and smoke detectors. There is a common misconception that such devices or items are exempt from all regulations. All such radioactive sources are subject to regulation. The University is responsible for ensuring that such devices are used as intended by the manufacturer, are not lost, tampered or stolen, and are properly disposed. Contact RSS (764-6200) before acquiring or disposing of such devices.

Radiation-generating Machines

Machines that generate ionizing radiation (e.g x-ray machines) must be registered with the Department of Licensing and Regulatory Affairs (LARA) prior to use. The LARA maintains a registry that identifies each machine including the exact location of the machine. LARA regulations require that RSS notify them of changes to registration information including when the machines are to be relocated, sold or disposed. You must notify RSS whenever you intend to relocate, sell, trade-in or dispose of such machines. OSEH must clear all such machines prior to sending to Property Disposition.