Environmental Health and Safety

Radiation Safety Training Manual

Waste Management

1. General

All containers for radioactive waste will be provided by Radiation Safety Staff. All waste should be doubly contained by using two plastic liners for solid waste and a secondary container for liquid waste.

The laboratory must segregate radioactive waste by half-life, chemical and physical form. Short-lived isotopes (e.g., 32P, 35S, and 125I) each require their own waste container. Longer-lived materials such as 3H and 14C may be combined in the same container as long as their activities are listed separately.

The radioisotopes in each container must be specified on either the affixed tag or label before depositing waste. A reasonable estimation of the activity must be made for each radioisotope prior to pickup by EH&S. You should not attempt to estimate the activity of any waste using a Geiger counter. You must either make a reasonable estimate from the use log maintained in the lab or, in the case of liquid waste, sample the waste and count on a liquid scintillation counter. This data can be used to calculate activity for the entire jug. In addition, the name of the PI and the date the activity was estimated must also be indicated on the tag.

Waste should never be intentionally stored in the lab for decay.

Call EH&S at 4-6778 or 4-6879 to arrange waste pickups. Usually we can pick up the waste and provide replacement containers in the same day. Because occasionally we are unable to pick up the waste in the same day, plan ahead to ensure adequate container space is available before starting a procedure.

With any radioactive material, appropriate consideration should always be given regarding potential exposure. This is particularly important when working with gamma emitting or high energy beta emitting isotopes. An effort should always be made to keep radiation exposures as low as reasonably achievable or ALARA.

2. Solid Radioactive Waste

The container for solid radioactive waste will usually come unassembled with two plastic liners. Laboratory personnel will have to assemble the box and place both of the liners in the box (one inside the other).

No pourable liquids are allowed. All liquid must be decanted into a container provided by EH&S. Gels may be placed in the solid waste box.

Do not place contaminated lead, animal tissue, biohazardous or infectious materials in the solid waste. Any radioactive biohazards or infectious radioactive waste must be sterilized prior to inclusion in the waste box. All biohazard insignias must be defaced before placing in the waste box.

All liquid scintillation vials must be reasonably emptied and segregated as dry waste. Vials previously containing 14C or 3H solutions must be segregated from all other solid waste and placed into another waste container provided by EH&S.

All radioactive sharps (e.g., needles, blades, or Pasteur pipettes) need to be segregated in some type of rigid container prior to their inclusion in the solid waste box.

The laboratory is responsible for taping the bags closed and sealing the box prior to pickup by EH&S. Regular masking tape is acceptable.

3. Liquid Radioactive Waste

Segregation by isotope should be done in the same manner as solid waste. Under no circumstances may radioactive liquids be disposed in a sink.

Containers for liquid waste must be kept sealed using the cap provided when not in use.

Radioactive solutions which are organic (e.g., ether, xylene, toluene, hexane, alcohol etc.) need to be segregated in a separate jug whenever possible. The chemical constituents and their relative percentages by volume must be identified on the waste tag.

Rinses of gels or other items resulting in the generation of liquids which are radioactive must be considered radioactive waste and disposed appropriately. Contact the Radiation Safety Officer with any questions regarding potentially radioactive rinses.

Do not overfill the container. There is usually a fill line which should not be exceeded. Generally, do not fill beyond 3/4 full. Call Radiation Safety for waste pickup when approaching this capacity.