Radioactive waste
Guidance on how to package, separate, label, store and dispose of radioactive waste on the St. George campus, including what constitutes radioactive waste and special cases.
Radioactive waste activities are carried out under the U of T consolidated NSRD licence.
All radioactive waste is either shipped to AECL Waste Management Systems or a licensed contractor for disposal or held for decay.
What is radioactive waste?
Radioactive waste includes:
- Surplus radioisotope material in any form (for example, surplus materials in supplied form, sealed sources, etc.)
- Material that has come into direct contact with radioactive material (for example, gloves, culture dishes, pipettes, flasks, etc.).
- Materials used for radioactive decontamination (for example, paper towels, sponges, etc.).
- Materials that have come into incidental contact with radioactive material (for example, bench top covering material, etc.).
- Contaminated equipment used during radioisotope handling procedures that is no longer required and cannot be cleaned (for example, centrifuges, gel electrophoresis equipment, etc.).
Packaging radioactive waste
In addition to the general packaging requirements outlined in Section 4, the following specific requirements for radioactive waste must be followed.
Radioactive waste must not be placed in non-radioactive waste containers. Likewise, non-contaminated items should not be placed in radioactive waste containers.
Separating radioactive waste
Radioactive waste must be separated in the laboratory. Solid waste must be separated from liquid radioactive waste. Solid and liquid waste must be separated according to individual waste blocks. Each waste block has a specific characteristic based on its physical state (solid or liquid), and in the case of liquid waste, the radioisotope’s physical half-life and type of solvent. Failure to comply with the separation scheme outlined below may result in waste being refused at the disposal facility and returned to U of T property.
Radioactive waste must be separated according to the requirements outlined in the table below.
Segregation requirements for radioactive waste
| Waste block ID | Description | Colour-coded jars for liquid wastes |
|---|---|---|
| 9100 | All solid waste containing all nuclides – no isotope segregation | Not applicable |
| 9101 | Liquid scintillation vials and fluids | Not applicable |
| 9102 | Aqueous radioactive liquids for delay-decay | Green label for isotopes such as |
| (<30 day half life) | P-32, P-33, I-131, Cr-51 | |
| 9103 | Aqueous radioactive liquids for delay-decay | Blue label for isotopes such as |
| (30-90 day half life) | S-35, Fe-59, I-125 | |
| 9104 | Aqueous radioactive liquids for delay-decay (>90 day half life) | Yellow label for isotopes such as C-14, H-3, Ca-45 |
| 9105 | Organic radioactive liquids | Consult with Environmental Protection Services |
| (all nuclides) |
Solid radioactive waste
- Solid non-sharp waste for disposal must be placed in yellow bags in the designated radioactive waste containers. Radioactive waste must not be placed in standard green or black garbage bags under any circumstances.
- Any long rigid plastic tubing, long plastic pipettes or similar material must be wrapped in several layers of bench topping or similar material and taped securely.
- No sharp waste (glassware, needles and blades) should be placed in the solid waste containers. View the waste procedures for sharp waste.
- Solid waste must not contain any viable biological agents or materials. View waste procedures for radioactive material containing a hazardous chemical or biological agent.
- Non-contaminated material, including foodstuffs or food containers, is not allowed in the solid radioactive waste container.
Liquid radioactive waste
This section applies to all liquids containing radioactive material except liquid scintillation counting fluid in vials (refer to Section 5.3.5(d)).
- Radioactive liquid waste is segregated according to half lives of the isotopes. Colour-coded jars based on the segregation criteria outlined in Table 1 are distributed free of charge to laboratories for liquid wastes.
- Liquids containing radioactive material must be poured into plastic bottles containing absorbent material, which are provided by the Environmental Protection Services team for the collection of radioactive liquid waste. If the liquid is likely to dissolve the standard plastic container, the permit holder must contact the Environmental Protection Services team for help.
- Following the addition of liquid waste to the bottle, the attached waste tag must be fully completed.
- The outside of the bottle must be clean and free of wet or dried liquids, and of any hazardous biological or chemical agents. Liquid wastes must not contain any viable biological agents.
- No liquid containing radioactive materials may be disposed of through the laboratory sanitary sewer system, except for water used to wash lightly contaminated glassware that meets the U of T guidelines outlined in Table 2.
Aqueous washes
- Aqueous liquid waste resulting from experiments with radioactive materials often contains insignificant amounts of activity, defined by the Canadian Nuclear Safety Commission (CNSC) as non-radioactive. Table 2 identifies commonly used radioisotopes found in such liquid waste. If the quantity of radioactivity is below the U of T release criteria outlined in column E in Table 2, the CNSC considers the hazard to be not radioactive and insignificant.
- Any aqueous liquid waste meeting the criteria in column E in Table 2 may be disposed of in the regular drain, followed by several litres of running water to ensure that the sink trap is flushed completely.
- Any non-aqueous waste meeting the criteria in column E in Table 2 should be disposed of as chemical waste. Refer to procedures in Section 5.2.
- Activities discovered in any liquid waste above the levels in column E, Table 2, must be disposed of in the appropriate liquid waste container identified in column F, and the tag identifying the contents completed.
U of T release criteria for individual radioisotopes in aqueous liquids
| A | B | C | D | E | F |
|---|---|---|---|---|---|
| Radioisotope | LS counter efficiency (%) | CNSC C-222 release quantity (µCi) | CNSC limit 1% of CNSC limit/litre of wash (µCi) | U of T limit (For 1 litre or more aqueous flush) | Levels >column E must be disposed as radioactive liquid waste in colour-coded waste containers (see Table 1) |
| Calcium 45 | 95 | 10 | 0.1 | 2.1*10 5 cpm/litre of wash | Yellow |
| Carbon 14 | 95 | 100 | 1.0 | 2.1*10 6 cpm/litre of wash | Yellow |
| Chromium 51 | 35 | 100 | 1.0 | 7.7*10 5 cpm/litre of wash | Green |
| Hydrogen 3 | 50 | 1000 | 10 | 1.1*10 7 cpm/litre of wash | Yellow |
| Iodine 125 | 95 | 1 | 0.01 | 2.1*10 4 cpm/litre of wash | Blue |
| Iodine 131 | 95 | 1 | 0.01 | 2.1*10 4 cpm/litre of wash | Green |
| Iron 59 | 95 | 0.27 | 0.0027 | 5.7*10 3 cpm/litre of wash | Blue |
| Phosphorus 32 | 95 | 10 | 0.1 | 2.1*10 5 cpm/litre of wash | Green |
| Phosphorus 33 | 95 | 27 | 0.27 | 5.7*10 5 cpm/litre of wash | Green |
| Sulphur 35 | 95 | 10 | 0.1 | 2.1*10 5 cpm/litre of wash | Blue |
Radioactive liquids containing significant amounts of organic material
Any radioactive liquid waste containing significant amounts of organic solvents or material must be kept separate from non-organic liquid waste.
Using a separate plastic bottle to collect radioactive liquid waste is acceptable unless the solvent dissolves the plastic.
Separate arrangements may be required to collect radioactive liquid waste containing significant amounts of organic solvents or materials.
Labeling radioactive waste
Information (permit number, date, isotope and radioactivity) must be legibly and accurately recorded on the accompanying tag as waste is added.
If the liquid waste added to the bottle contains organic or aqueous solvents, complexing or chelating agents (for example, EDTA), this must be noted on the accompanying waste tag.
See Figure 2 for an example of a completed radioactive liquid waste tag. See Figure 3 for an example of a completed radioactive solid waste tag.
Storing radioactive waste
Each radioisotope laboratory should establish one location for the consolidation of radioactive waste. The location of the radioactive waste consolidation area(s) should be identified.
More than one location may be used if the laboratory is large, has more than one area in use, and these areas are widely separated. If more than one radioactive waste consolidation area exists in a radioisotope laboratory, it is the responsibility of the laboratory staff to ensure that the Environmental Protection Services team is aware of these locations.
Any form of shielding material used around a designated waste consolidation location must be designed, constructed and used in such a way that allows access by the Environmental Protection Services team.
Radioactive waste should not be stored beneath any working area, whether this is used for work with radioisotopes or not. Radioactive waste should not be stored in the vicinity of personnel who do not work with radioactive materials.
Special cases
Animal carcasses
- Radioactive animal carcasses must be completely and securely wrapped and have a label attached. The label must show the permit number, species, number of carcasses, date, isotope and maximum activity per animal carcass.
- Radioactive animal carcasses for disposal must be kept in an identified, designated freezer or cold room. It is the responsibility of the laboratory staff to transport the carcasses to that location until removed by the Environmental Protection Services team.
Gas chromatograph units
- Gas chromatograph units may have a radioactive source incorporated into the unit. If a gas chromatograph unit is to be sent for disposal, the senior radiation safety officer must be notified in writing to arrange for the deletion of the unit from the associated permit. The Environmental Protection Services team will arrange for the removal of the source from the laboratory.
Gaseous radioactive waste
- U of T does not normally generate significant quantities of radioactive gaseous waste. Any process that is likely to produce radioactive gaseous discharges must be performed in a fume hood.
- A permit holder must submit all proposals that have the potential to generate significant quantities of gaseous wastes to the U of T Institutional Radiation Protection Committee for prior approval. Information on any planned control measures and personal protective equipment must also be supplied.
Liquid scintillation counting vials
- Liquid scintillation counting vials must be marked for disposal. Any vials not marked will not be accepted by the Environmental Protection Services team.
- Vials must have caps that are securely fastened. Vials must not be leaking or show evidence of leaking.
- Vials for disposal may be placed either in the original trays or in waste containers specifically identified for vials only. The construction and integrity of whichever container is used must be sufficient to withstand normal handling and contain any potential leakage.
- Glass and plastic scintillation vials must be kept separated for collection.
- Liquid scintillation counting vials must not contain any viable biohazardous agents. All biological agents must be inactivated. Refer to Section 5.1 for inactivation procedures.
Liquid scintillation counters
- Liquid scintillation counters may have a radioactive source incorporated in the counter. The requirements for the disposal of gas chromatograph units apply. If a liquid scintillation counter is to be sent for disposal, the senior radiation safety official must be notified in writing to arrange for the deletion of the counter from the associated permit. The Environmental Protection Services team will arrange for the removal of the source from the laboratory.
Radioactive material containing a hazardous chemical or biological agent
- Where the liquid contains radioactive material and hazardous biological agents, the latter must be inactivated before being released to the Environmental Protection Services team for collection. See Section 5.1 for information on inactivation procedures.
- Where the radioactive liquid contains significant quantities of chemicals, the chemicals must be inactivated or neutralized before disposal.
- If the hazardous chemical or biological agent cannot be inactivated or neutralized, the manager of the Environmental Protection Services team must be contacted for help.
Refrigerators, freezers and other equipment
- All refrigerators, freezers and other equipment that contain radioactive material, were previously used in radioisotope research and are no longer required must be thoroughly decontaminated. The permit holder is responsible for ensuring that all radioactive material is removed and the unit is free of any surface contamination.
- The permit holder must ensure that all radioactive warning labels are removed or defaced to eliminate any reference to radioactive material.
- Following decontamination, radiation protection services must be notified. They will confirm the decommissioning of the unit and arrange for its removal from the laboratory.
Sealed sources
- The Environmental Protection Services team will arrange for the removal and disposal of any unwanted sealed sources. The permit holder must notify the radiation protection services in writing of the intention to dispose of the sealed source to arrange its deletion from the associated Permit. The Environmental Protection Services team will arrange for the removal of the source. If the source is of a large activity or a unique nature, costs associated with its disposal may be charged to the department or permit holder. This includes the proper disposal of smoke detectors which contain a small radioactive source.
Sharps
- For sharps contaminated with radioactive materials, refer to Section 5.5.1.2 (c).
Shipping boxes
- Cardboard or other outer boxes used for the shipment of radioactive materials do not normally become contaminated. If the swipe test of the inner shipping containers (used to contain the radioactive materials), as received, is non-contaminated, it can be assumed that the outer shipping box is also non-contaminated.
- Any radioactive warning labels on the exterior of a non-contaminated shipping box must be removed or defaced in a way that eliminates any reference to radioactive material. The shipping box may be crushed or flattened and may be placed with non-radioactive waste for routine disposal or recycling. Interior packaging material designed to minimize impact damage (for example, foam chips, sponge rubber, etc.) may be recycled or placed with the regular non-radioactive waste for disposal.
- If a shipping box has become contaminated with radioactive material, it must be treated as radioactive waste, as per the requirements outlined for solid waste in Section 5.3.2.2. Any interior packaging (for example, foam chips, cardboard separators, etc.) must also be treated as radioactive waste.
Shipping containers (with lead shielding) from radioisotope shipments
- A radioisotope shipping container with lead shielding must be swipe-checked to ensure that it is free of radioisotope contamination. Containers must be clean and free of any obvious contamination by chemical or biological agents. Radioisotope shipping containers with lead shielding that are free of contamination will be collected separately by the Environmental Protection Services team.
- Any container that is contaminated must be marked as such and packaged separately before pick up. The container must not be placed together with the solid radioactive waste.
- Shipping containers must not contain free liquids. The liquid is to be disposed of according to the procedures outlined in Section 5.3.2.3.