Purpose

The purpose of this procedure is to ensure the proper disposal of radioactive waste in accordance with regulations, and to ensure that radiation protection work at NTNU complies with regulatory requirements and safeguards the safety of employees, students, and others at NTNU.

Scope and anchoring

This procedure applies to all units that generate radioactive waste from the use of open radioactive sources, and all units that permanently take sealed radioactive sources out of use.
The procedure does not apply to radioactive discharges to air or wastewater.

The Guideline for radiation protection and use of radiation sources serves as the governing framework for this procedure.

Definition

Refer to the glossary (at the end of the procedure).

Responsibility

Line Manager

The line manager has overall responsibility for ensuring proper radiation protection within the unit. The line manager shall fulfill the tasks described in the Guideline for radiation protection and use of radiation sources.

The line manager shall ensure that radioactive waste is handled in a way that does not pose a risk to humans, animals, or the external environment. This includes ensuring that the unit has access to, or maintains, a suitable storage facility for radioactive waste.

Procedure for disposal of radioactive waste

Academic supervisor

The academic supervisor shall perform tasks as described in the Guideline for radiation protection and use of radiation sources. In addition, when disposing of radioactive waste, the academic supervisor shall ensure:

• Specification of applicable waste routines and training in these routines for all involved personnel.
• Development of procedures for transport of radioactive waste from the laboratory to the waste storage facility. Such transport shall only be carried out by users of radiation sources or the technical responsible person themselves.

Users of radiation sources

Users of radiation sources shall perform tasks as described in the Guideline for radiation protection and use of radiation sources. In addition, when disposing of radioactive waste, users shall ensure:

• Clarification of waste disposal procedures before commencing use of radioactive sources.
• Disposal of radioactive waste at least once per year.
• Proper packaging of the waste.
• Labelling of the waste.
• Delivery of the waste to the radioactive waste storage room (e.g., DU4-174 in the Science Building).
• Verification that the radioactive waste is properly packaged and sufficiently labelled.
• Disposal of waste that has been stored and is no longer radioactive.
• Declaration of the waste.
• Agreement with the recipient of the waste.
• Contact with the transporter of the waste.
• Participation in the preparation of transport documentation.
• Logging all data related to the handling of radioactive waste in a dedicated protocol. Each department shall maintain its own protocol.

Local radiation protection coordinator

The Local Radiation Protection Coordinator shall carry out tasks as described in the Guideline for radiation protection and use of radiation sources. In addition, regarding the disposal of radioactive waste, the Local Radiation Protection Coordinator shall ensure:

• That the declaration forms for radioactive waste are properly completed and that the waste is disposed of correctly. This shall be done in collaboration with the hazardous waste and chemical waste disposer, as well as with the users who generate radioactive waste.
• That the storage of radioactive waste complies with the requirements outlined under Storage of radioactive waste.

Central radiation protection coordinator

The Central radiation protection coordinator shall carry out tasks as described in the Guideline for radiation protection and use of radiation sources. In addition, regarding the disposal of radioactive waste, the Central Radiation Protection Coordinator shall ensure:

• Contact with local radiation protection coordinators to assess the need for radioactive waste disposal around October 1st each year and facilitate communication among local coordinators responsible for disposal of such waste.

Room responsible person

Shall:

• Open the waste storage room for users who need to deposit radioactive waste.
• Have overall supervision of the waste storage room.

General handling of radioactive waste

Radioactive waste shall be managed in accordance with Chapter 16 of the Waste regulations as well as the Regulations on radioactive pollution and waste.

All handling of radioactive waste shall be performed in a way that avoids or minimizes exposure to personnel and prevents contamination of areas or equipment with radioactive material. How the waste is handled depends on:

• Whether the waste is subject to disposal requirements or not
• The type of radiation (alpha, beta, or gamma radiation; see Table 2 in the appendix: Disposal of radioactive waste)
• Whether the source is open or sealed

Waste with specific activity above the limits in the Regulations on radioactive pollution and waste, Appendix I, letter a, but below the limits in Appendix I, letter b, shall be declared as radioactive waste (see Table 1 in the appendix). If the waste contains more than one radionuclide, the summation rule in Appendix I, letter b shall be used to define disposal obligations.

Radioactive waste must be delivered at least once a year (section 16-7 in the Waste regulations).

Flammable non-radioactive substances and materials must not be placed in containers designated for radioactive waste.

Radioactive waste to be disposed of as hazardous waste after deactivation must not contain:

• Hazardous materials (poisons, lead or similar)
• Other hazardous waste
• Sharp non-contaminated objects (e.g., needles, razor blades)

Reducing the amount of radioactive waste

• Use techniques without ionizing radiation sources whenever practically possible.
• Check if other relevant units at NTNU have available equipment for non-radioactive techniques.
• Use isotopes with the lowest possible radiological toxicity and/or shortest half-life. For example, P-32 can be replaced with P-33.
• Plan experiments to minimize the amount of waste generated.
• Handle materials carefully to reduce the risk of contamination.
• Store waste with short half-lives (under approximately 40 days) until it can be further handled as hazardous waste, provided this is done within one year. See limit values in the Regulations on radioactive pollution and waste, Appendix I, letter A.

Use of protective equipment when handling radioactive waste

The following protective equipment/tools shall be used when handling radioactive waste:

• For handling all radioactive waste:
  • Laboratory coat
  • Gloves
• For handling waste containing open radioactive sources:
  • Use of safety glasses and respiratory protection should be considered.
• For handling waste emitting gamma radiation:
• • Dosimeter (measuring instrument for dose rate, µSv/h)
  • For Cd-109 / I-125 / I-129: Lead apron/lead coat
    • Should NOT be used with other gamma sources (higher gamma energy) as it gives a false sense of security
  • Additional lead shielding as needed (see Table 2 in the appendix: Disposal of radioactive waste)
• In waste storage rooms for waste emitting gamma radiation:
  • For dose rates above 7.5 µSv/h, consider:
    • Use of personal dosimeter
    • Logbook where all time spent and estimated radiation doses are recorded

Sorting radioactive waste

Radioactive waste is sorted based on:

• Half-life and specific activity
• Type of radiation (alpha, beta, or gamma)
• The physical form of the waste

Beta and gamma emitters require different shielding and should generally always have separate waste containers. However, if beta emitters and gamma emitters are used in the same experiment and thus occur together in the waste, they can be stored together, provided that the container has shielding adapted to the gamma emitters in the waste. In some cases (usually when the waste contains P-32), there may be a need for a plexiglass container with lead shielding on the outside.

Waste containing radionuclides with short half-life

Waste with a short half-life that will fall below the specific activity limit in the Regulations on radioactive pollution and waste, Appendix I, letter A, within 1 year, shall be stored until the specific activity is below the limit. NTNU has permission to store I-125 for up to 2 years if the activity within that time has fallen below the limit. See more information about packaging and labeling of radioactive waste for intermediate storage.

When the waste has fallen below the specified limit, the labeling shall be removed and it shall be handled as non-radioactive waste.

For contaminated equipment (empty tubes, gloves, paper, etc.) in waste containers, the average specific activity in the container can be calculated. When calculating how long the waste should be stored, the total activity of the radionuclide in the waste container is divided by the net weight of the waste in the container (the weight of the container itself should not be included). Non-radioactive waste must not be mixed in.

Solutions and samples with higher specific activity shall be collected in separate containers.

If there is not enough information about the total activity to perform the calculation, the waste shall continue to be treated as radioactive waste after storage.

Solid radioactive waste

Solid radioactive waste includes powders, paper, gloves, clothing, contaminated laboratory equipment, contaminated shoe covers, and similar materials.

• Solid waste must be disposed of in designated containers with lids.
• Containers should not be so full that the lid cannot be securely closed.
• Radioactive pathology waste must be labeled and stored securely in a freezer designated for this purpose. Both the waste container and the freezer must be marked with the symbol for radioactivity/ionizing radiation.
• Solid and liquid radioactive waste must not be mixed. Scintillation counting liquids must be disposed of separately.

Liquid radioactive waste

Radioactive liquid waste includes the radioactive material as well as the liquid from any initial cleaning of equipment or containers.

Liquid waste shall be collected in designated containers that are resistant to the various solvents and radioactivity. These containers should be placed inside a secondary container large enough to hold the contents of the primary containers in case of spills.

Solutions containing a mixture of radioactive material and hazardous/toxic substances, as well as scintillation liquids, require special handling (see further details below).

Excreta from experimental animals may be discharged into the sewage system without regard to activity limits.

It is not permitted to dilute radioactive waste to reduce it below the limits stated in the Regulations on radioactive pollution and waste, Appendix I.

Scintillation counting liquid

Scintillation counting liquid waste can be disposed of as hazardous waste (not radioactive waste) provided the specific activity is below the limits specified in the Regulations on radioactive pollution and waste, Appendix I, letter A. The scintillation liquid shall be collected in dedicated containers for hazardous waste. Note: Do not fill containers so full that the lid cannot be securely closed.

When the container is full, calculate the volume of counting liquid (liters), the total activity in becquerels (Bq) (dpm:60), and the activity per gram (Bq/g) in the container. This information must be recorded both in a logbook and on the container. When the container is placed in the waste room, all containers must be labeled with the following:

• Scintillation liquid
• Volume (liters)
• Total activity (Bq)
• Activity per gram (Bq/g) (1 ml counting liquid ≈ 1 g)
• Radionuclide
• Name of institute
• Name of contact person
• Date

Containers with scintillation counting liquid waste shall be stored for a maximum of 90 days before disposal.

Sharp objects and contaminated disposable equipment

Sharp and pointed objects, as well as disposable equipment used during work with radioactive material, shall be disposed of in separate, shielded containers. It is important that the waste is packed in a way that prevents cutting or puncturing injuries during handling. Shielding must be chosen according to the type of radiation.

When the container is full, it shall be packed into a box labeled hazardous waste and treated as solid radioactive waste.

Glass waste contaminated with radioactive substances

Glass waste contaminated with radioactive substances above the exemption limits shall be handled as solid radioactive waste.

Glass waste contaminated with radioactive substances below the exemption limits specified in the Regulations on radioactive pollution and waste, Appendix I, letter A, shall be collected in a separate hazardous waste box and handled as sharp/cutting waste.

If it is impossible to calculate the specific activity, contaminated glass waste must be handled as radioactive waste.

Radioactive waste subject to disposal requirements

The table in the Regulations on radioactive pollution and waste, Appendix I, letter b, specifies threshold values for total activity (Bq) per year and for specific activity (Bq/g) for each radionuclide. Waste is subject to disposal requirements if BOTH of these threshold values are met or exceeded.

It can be expected that NTNU, as an institution, will exceed the threshold value for total activity (Bq) per year. Therefore, it is the specific activity in each waste unit (box/drum/other) that determines whether the waste is subject to disposal requirements or can be delivered as radioactive waste.

The weight of the waste itself shall be used as the basis for calculating specific activity, not the weight of the packaging.

If the waste contains more than one radionuclide, the summation rule specified in the Regulations, Appendix I, letter b, shall be used to determine the disposal obligation.

Packaging and labeling of radioactive waste

Packaging for radioactive waste shall be clean, sturdy, and leak-tight, and suitable for transport and storage of the waste.

All boxes/containers with radioactive waste must be clearly labeled with:

• Symbol for radioactivity/ionizing radiation
• Institute
• Name of the user who produced the waste
• Date
• Type of radionuclide
• Estimated activity

For temporary storage of radioactive waste, the packaging shall also be labeled with:

• Specific activity for each individual radionuclide
• If applicable, the date when the specific activity is expected to be below the threshold for radioactive waste according to the Regulations on radioactive pollution and waste, Appendix I, letter a
• If applicable, any other hazardous waste (e.g., scintillation fluid)

If the radiation level exceeds 7.5 µSv/h on the outside of boxes/containers with waste, they must also be shielded.

If the waste is stored until the specific activity is below the threshold in the Regulations on radioactive pollution and waste, Appendix I, letter a, the labeling must be removed before the waste is disposed of.

Storage of radioactive waste

Radioactive waste shall generally be delivered at least once per year (section 16-7 in the Waste regulations). NTNU has been granted an exemption from the annual delivery requirement for up to 2 years for I-125. Sealed sources permanently taken out of use shall not be stored on NTNU premises for more than 1 year.

Radioactive waste shall be temporarily stored in designated rooms/locations with strict access control.

• The storage area for scintillation fluids shall be well ventilated.
• Biological/pathology waste shall be stored in a freezer.

The storage facility shall maintain a list of persons with access and an overview of the radioactive waste, including radionuclides, activity levels, and estimated date when the waste will be below the activity limit for radioactive waste.

The storage area shall be marked with hazard signs for ionizing radiation according to the Workplace Regulations, Chapter 5. Room cards should also be posted.

Outside the storage facility, in areas accessible only to employees, radiation levels shall not exceed 7.5 µSv/h.

Outside the storage facility, in areas accessible to the public, individuals shall not be exposed to more than 0.25 mSv per year.

Radioactive waste that has been deactivated shall be disposed of as hazardous waste. All symbols for radioactivity shall be removed from all radioactive waste once the waste has been deactivated.

Declaration and shipment of radioactive waste and scintillation fluids

Waste must be declared through https://www.avfallsdeklarering.no/. See appendix: Disposal of radioactive waste for information on declaration, handling, classification, and shipment of all types of radioactive waste and scintillation fluids.

Waste transporters are authorized to transport radioactive waste but are not permitted to store this type of waste temporarily. The disposer must contact the recipient before shipment to ensure the transporter can deliver the waste. See appendix: Disposal of radioactive waste.

Sealed Radioactive Sources

When disposing of sealed radioactive sources, these are normally returned to the supplier. Contact the supplier to arrange acceptance. If the supplier is unknown, the Institute for Energy Technology (IFE) at Kjeller can be contacted. See appendix: Disposal of radioactive waste for further description.

Release of radioactivity

The release of radioactivity into air or sewage requires a separate permit from the Norwegian Radiation and Nuclear Safety Authority (DSA). It is not permitted to discharge small amounts of radioactive substances if it can be avoided. Dilution and disposal of small quantities of radioactive materials down the drain must not occur. Please contact the local or central radiation protection coordinator for further information.

Glossary

Radioactive waste subject to disposal requirements:
Radioactive waste with activity greater than or equal to the values specified in the Regulations on Radioactive pollution and waste, Annex I letter b.

dpm (disintegrations per minute):
The number of radioactive disintegrations per minute. Becquerel (Bq) is obtained by dividing dpm by 60. Bq equals disintegrations per second (dps). When using a scintillation counter, activity is often measured in counts per minute (cpm). To convert to Bq, the count must be adjusted for counting efficiency. It is recommended to calibrate the counter against a known source to determine counting efficiency.

Hazardous waste:
Waste that can cause harm to animals, humans, or the environment if not properly handled. Must be sent to approved disposal facilities.

Radioactive waste:
Discarded objects, solutions, or substances considered waste according to the Pollution control act section 27 first paragraph, consisting of or contaminated with radioactive material with specific activity greater than or equal to the values specified in the Regulations on Radioactive Pollution and Waste, Annex I letter a.

Risk waste:
Biologically hazardous waste; sharp objects/needles, infectious materials, pharmaceutical residues, and similar.

Specific activity:
Bq per gram (Bq/g).

Open radioactive sources:
Radioactive material that is not encapsulated.

Encapsulated radioactive sources:
Radioactive material that is encapsulated to prevent the spread of radioactive substances to the environment.