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Radioactive Waste Guidelines

Only radioactive materials that are on the PI’s permit may be discarded through EH&S.  If the material is not listed, please contact Radiation Safety. 
Radioactive wastes must be segregated by PI, isotope, and type of radioactive waste.

By PI:

Radioactive isotope usage is tracked by PI.  Therefore, in common-use rooms, radioactive wastes must be kept separated from other PI’s wastes, even if they are of the same type.

By Isotope:

  • Long-lived isotopes (ex. 3H and 14C) may be consolidated in the same collection container provided they are the same type of waste and generated under the same PI. Please consult EH&S for guidance regarding other long-lived isotopes.
  • Short-lived isotopes, including any material with a half-life less than 90 days, must be:
    • Separated from each other whenever possible.
    • Segregated from long-lived isotopes.
    • Held for decay-in-storage by the lab or EH&S.  After decay and clearance, all radioactive labels and markings must be completely defaced or removed prior to disposal in the waste collection container.

Decay-in-storage guidelines:

  • A log with collection dates, activities, and isotopes must be maintained by the lab.
  • EH&S can provide space for decay-in-storage upon request, if necessary.  Please submit a radioactive waste pickup request.
  • The minimum required storage time is 10 half-lives of the isotope being decayed. The amount of activity remaining after ten half lives is approximately 1/1000 of the original amount.
  • If more than one isotope is commingled in the waste, it must be stored for a minimum of 10 half lives of the slowest decaying component. After the waste has been stored for at least 10 half-lives, the waste must be checked for any radioactivity using the appropriate survey device at the lowest scale. The reading must be the same as the background level and all results must be recorded.

After decay, the waste will be disposed of as non-radioactive waste through EH&S. All radioactive labels must be removed or destroyed before discarding the items.  Final clearance must be completed by EH&S, please email rsoresearch@columbia.edu to request service.

By Radioactive Waste Type: 

Every effort must be made to minimize waste volumes. Accordingly, each type of radioactive waste must be separated.  Animal/biological, beta plates/96-well plates, dry solid waste, liquid scintillation vials, liquid waste must be separated from each other.  Please see the following guidelines for disposal of several common radioactive waste streams.

Animal / Biological

  • EH&S arranges periodic shipments of radioactive animal carcasses through an email communication to licensed PIs.  Additionally, if a lab generates radioactive animal carcasses, advanced notification may be made by submitting a radioactive waste pickup request.
  • Radioactive carcasses must be frozen prior to pick-up by EH&S.
  • Radioactive carcasses containing isotopes with half-lives less than 90 days must be held for a minimum of 10 half-lives by the lab for decay-in-storage (see above).  After decay, the lab should submit a request for clearance by emailing rsotech@columbia.edu.
  • Radioactive carcasses with half-lives of greater than 90 days with an activity of greater than or equal to 0.05 uCi/g averaged over the weight of the animal must be arranged for disposal by EH&S by submitting a radioactive waste pickup request.
  • Animal bedding and feces may be disposed of as biological radioactive waste by submitting a radioactive waste pickup request
  • Red bags must only be used for potentially infectious materials, and not as a general liner for a radioactive waste container or for radioactive spill debris.

Beta Plates/96-well plates
Dry Solid Waste
Liquid Scintillation Vials (LSV)
Liquid Waste

Smoke Detectors and Exit Signs Disposal
Please refer the EH&S Health & Safety manual
section 4.5 for additional information.