Use the information below to ensure that your radiation exposure is as low as reasonably achievable (ALARA). As always, if you have any questions, please contact the radiation safety office at (512) 471-3511 or firstname.lastname@example.org.
Ordering Radioactive Materials
The process for ordering radioactive materials is partially automated, but there are a few steps that must be taken.
- Radioactive materials must be ordered using a Purchase Order. Use of a procurement card is strictly prohibited and may result in the card being revoked.
- Notify your purchasing agent that the order is for radioactive materials so that they can enter the correct commodity code.
- In addition to the vendor item number, include the following information
- Isotope (e.g. P-32, S-35, H-3, C-14, et cetera…)
- Activity in millicuries
- Authorized User Number
- Chemical form of the product
- When the purchasing agent enters the commodity code for radioisotopes and submits the request, the system will automatically verify the authorization details with the EHS Radiation Safety database. Once the system accepts the request, and the PO number is generated, the order may be placed with the vendor.
Further details can be found in the Radioactive Materials Ordering Procedure (DOC)
Receiving Radioactive Materials
- All radioactive deliveries must be inspected by Radiation Safety staff or designated personnel approved by the RSO.
- Radioisotopes with White I, Yellow II, or Yellow III labels must be surveyed for contamination by Radiation Safety staff if delivered to main campus or Dell Medical School. State and federal regulations require that the survey be performed within three hours of receipt.
- For deliveries to MSI and DPRI, designated personnel may perform the inspection. At these locations, Excepted Packages (UN2910 and UN2911) must also be surveyed. The same time requirement applies for all packages delivered to “remote” sites. The survey results must be scanned to pdf and sent to email@example.com.
- Radiation Safety Staff will deliver the material to the lab. Upon receipt, check that the package is not damaged and that it is the correct item ordered. The inner container shall be stored in the appropriate location in the lab.
- The radiation trefoil appearing on any surface must be defaced before disposal.
- Survey the interior and exterior of shipping containers before disposal.
More details on radioactive material receipt can be found here.
Waste Processing Procedures
Radioactive waste is picked up by the Radiation Safety Office on the last Tuesday of each month. There may be exceptions in the event of unexpected circumstances.
- Waste bins should be made of an appropriate material to provide some shielding of the radioactive waste.
Lined with led for gamma ray emitters (not necessary for low energy gamma emitters like I-125)
Plexiglas or sturdy plastic, at least 0.25” thick, for beta particle emitters
- Use clear or black plastic bags for collection. Bags displaying the radiation trefoil or biohazard symbol are prohibited. This includes smaller bags used for bench top waste. Waste must be dry with no standing liquids inside the bags. All radiation trefoils and biohazard symbols must be destroyed or defaced before being placed in the radioactive waste bin.
- Radioisotopes must be collected separately. Each isotope should have its own container. There are two exceptions to this requirement: H-3 (tritium) and C-14 may be collected in the same container.
- Aqueous, non-hazardous liquid radioactive waste may be disposed via sanitary sewer in a designated sink within the lab. If no such sink is available, liquid radioactive waste may be collected in a bulk liquid container. Bulk liquid containers should be made of sturdy plastic. Lids to all containers must be sealed completely to prevent leakage during transport. The exterior of the container should be surveyed by lab personnel for contamination. If your lab doesn't have the proper container please call EHS at (512) 471-3511 and one will be provided. Please do not use glass containers.
- If bulk liquid waste is water soluble and non-hazardous, all isotopes may be placed in the same container. Please label the container stating that the liquid is water soluble and what radioisotopes are in it.
- If the liquid waste is not water soluble put this waste in a separate container and identify the contents with a waste tag. Non-aqueous liquid waste must be separated by isotope.
- Mixing radioactive materials with other hazardous materials produces mixed waste. Producing mixed waste is prohibited without prior approval in writing by the Radiation Safety Officer.
- Fill out the waste pick-up form completely and send it to firstname.lastname@example.org.
For more information on processing radioactive waste, please review the procedures found here.
Weekly Contamination Surveys
Laboratories authorized to use radioactive materials are required to perform and document weekly surveys of the lab for radioactive contamination. For periods when no radioactive materials are present or in use, a survey need not be performed, but an entry in the survey log must be recorded to indicate that no radioactive materials were in use. An example survey log is available here.
Each survey entry requires six pieces of information:
- The date of the survey
- The instrument used, including the manufacturer, model, and serial number
- The background reading of the instrument.
To determine the background (bkg), turn the instrument on at its lowest setting, away from areas that may be contaminated and record the background in counts per minute (cpm).
If you are using a liquid scintillation counter, place a vial in the counter that does not contain a swipe sample, but does contain LSC cocktail. The exact procedure will vary depending on the manufacturer.
- The location of the survey, including the room number and a description of the area surveyed, such as a specific bench, fume hood, or piece of equipment. If the whole lab is surveyed, no specific description is required.
- The results of the survey. If contamination was discovered, you must clean the area and survey it again. LSC results may be attached to an individual survey record and/or stored in a binder. Survey results must be recorded in disintegrations per minute (dpm) / 100 cm2. To find this value, subtract the background from the cpm reading and divide by the instrument’s efficiency for a specific isotope.
- The name of the person who performed the survey.
More information on surveys can be found here.
Radiation Survey Instruments
It’s important to use the correct instrument for your radiation surveys and experiments. Contact the radiation safety office for assistance in determining which one is right for your needs. Here are some tips for maintaining your instrument:
- Survey instruments must be calibrated annually. Before using yours, ensure that it has been calibrated within the last year. If you find that your instrument is overdue for calibration, contact the radiation safety office.
- If your instrument is not working correctly, try checking the batteries. This is the most common issue. If there are still problems with the instrument, contact the radiation safety office.
- Store your instrument in a safe location. Environmental (cold) rooms can cause condensation inside your survey instrument that will cause it to malfunction.
- Turn your instrument on before you begin handling radioisotopes, and turn it off when it’s not in use to save the batteries.
- Ludlum survey instruments are the most common type found on campus. Here’s a useful guide to keep them in working order.
Radiation Spill Response
In the event of a spill, it’s important to remember that radioactive contamination can be spread beyond the spill area by the movement of personnel involved in the spill or clean-up effort. Prevent spread by confining movement of personnel until they have been monitored and found free of contamination. A minor radiation spill is one that the laboratory staff is capable of handling safety without the assistance of the Radiation Safety Department. All other radiation spills are considered major.
Minor Radiation Spill
- Alert people in the immediate area of the spill.
- Wear protective equipment, including safety goggles, disposable gloves, shoe covers, and a long-sleeve lab coat. Two layers of gloves may be appropriate.
- Place absorbent paper towels over liquid spills. Place towels dampened with water or decontaminant cleaner over spills of solid materials or powders.
- Use a foaming cleaning solution such as 409, No Count, Count-off, or RadCon to decontaminate the area. If such cleaners are not available, soap and water may be used instead.
- Using forceps or gloved hand, place towels in a thick plastic bag. Dispose in the appropriate radioactive waste container.
- Monitor area, hands, and shoes for contamination with an appropriate survey instrument. Repeat cleanup until contamination is no longer detected. For spills of H-3, C-14, or S-35, a swipe survey using a liquid scintillation counter is required.
- If assistance is needed, call Radiation Safety.
Major Radiation Spill
- Attend to injured or contaminated persons and remove them from exposure.
- Alert people in the laboratory to evacuate.
- Have potentially contaminated personnel stay in one area until they have been monitored and shown to be free of contamination.
- Call the Radiation Safety Officer and Radiation Safety Personnel.
- Close the doors and prevent entrance into affected area.