Radiation Safety Training: Procedures for Sealed Sources

University of Alaska Fairbanks

March 2022

Training Contents

1. UAF Radiation Safety Requirements
• Authorized and Supervised Users
• Requirements for labs
• Badges
• Ordering and receiving sealed sources
• Recordkeeping
• Leak tests and surveys
• Security
2. Emergency procedures

UAF RADIATION SAFETY PROGRAM�CLASSES OF USERS

Authorized User (AU):

is primarily responsible for the authorized use, supervision, and training of their laboratory personnel. This is typically a Principal Investigator.

Supervised User (SU):

is a staff member or student of at least 18 years of age and is supervised by the AU.

UAF Radiation Safety Requirements

UAF laboratories where sealed sources of radioactive materials are used must have:

1. A radioisotope use notebook for records. This is known as “The Redbook” and is often in a red binder for easy recognition.
• Notebook must contain a signed UAF Authorized User application and any signed Supervised User applications.
2. A specific notebook is used for users that only have sealed radioactive sources.

UAF Radiation Safety Requirements (cont.)

UAF laboratories where sealed sources of radioactive materials are used must have:

3. A secure location to store radioactive materials. This can be a locked room or a locked cabinet.
4. Access to a calibrated scintillation counter and calibrated Geiger counter (if appropriate) for conducting wipe tests and surveys.
• Calibrations must be done annually.
• Do not use a Geiger counter or scintillation counter that does not have a current calibration.

UAF Radiation Safety Requirements (cont.)

Transfer of radioactive sources from one user to another is prohibited without prior written approval from UAF Radiation Safety Officer (RSO).

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This is true regardless of the affiliation of the other person.

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UAF Radiation Safety Requirements (cont.)

Monitoring badges

• are issued to users of sources that contain high energy gamma emitters such as ¹³⁷Cs, and are required to be worn when working directly with such sources
• must be worn unshielded on the breast pocket or collar of shirt
• should only be worn when working with the source and should not be worn outside the lab
• should be stored away from radiation areas and protected from moisture, heat, and sunlight

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Ordering and receiving sealed sources of radioactive materials

Ordering sealed radioactive sources:

Notify RSO of your intent to order a sealed source containing radioisotopes and provide the names of the isotopes and their activities—BEFORE you order.

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In some cases, our NRC license will need to be amended in order to acquire the source, and this can take several months. Planning ahead is critical.

Recordkeeping for sealed sources

When a new sealed source arrives:

1. Check the package for damage. Check the contents to ensure that you have received what you ordered.
• If there is damage to the package or the container that holds the source, contact the RSO immediately.
• If there are discrepancies, contact the RSO and the vendor immediately.
2. Enter the information about the source on the Summary of Radioactive Materials Received form in the Redbook.

Recordkeeping for sealed sources (cont.)

3. Perform a leak test on the source prior to using it or within 5 days of receiving it. Contact the RSO if you need assistance with this.
4. If the source is found to be leaking, contact the RSO immediately so that the vendor can be alerted.
5. Store the source in its secure location.
6. Leak tests for sources that are in use must be performed every 6 months and documented. The RSO generally does this but may require assistance from the user.
7. Leak tests should be performed by the RSO if it is believed that the source may have been damaged.

Performing a leak test

1. Prepare a background wipe by wetting a piece of filter paper (Whatman #1 works fine) or a cotton swab with tap water and placing in a scintillation vial.
2. Use a damp piece of filter paper or a cotton swab to thoroughly wipe the surface of the source. You may need to use tongs in order to hold the source if it emits too much radiation to handle with your hands.
• Avoid touching areas of the source that are not encapsulated.
3. Add scintillation cocktail to each sample. Make sure the filter papers or swabs are completely covered with cocktail.
• Alternatively, swabs may be sent to a 3^rd party lab for analysis. Follow the instructions in the leak test kit.

Performing a leak test (cont).

4. Count the samples in a liquid scintillation counter. Use channels for the isotope(s) that you are using plus a “wide” channel (counts all energies).
5. Record results on lab survey form and attach printout from scintillation counter.
6. Determine level of contamination, if any.
1. If any wipe exceeds 0.005 µCi above background, the source is likely leaking.
2. Contact the RSO immediately and do not use the source.

UAF Radiation Safety Requirements (cont.)

Security of Inventory

AUs and SUs shall provide security adequate to prevent the unauthorized removal of any radioactive material that is under their control.

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All sealed sources of radioactive materials must be secured (locked storage cabinet or locked laboratory) when not in the direct line of sight of the AU or SU.

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Control access to laboratories. Close and lock all entry doors when laboratory is unattended.

UAF Radiation Safety Requirements (cont.)

Maintain an inventory of all radioactive sources. Conduct a visual check of sealed radioactive sources at least once a month. Exceptions to this rule are sources that are held by the RSO.

Know who is in your laboratory. Persons without appropriate justification for being in a lab should be asked to leave. Report concerns to proper authorities.

Report any missing inventory to the RSO immediately.

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Disposal of sealed sources

Unwanted or expired sealed sources of radioactive material must be transferred to the RSO and documented on a Transfer Form for Unwanted Sources (found in Sealed Source RedBook).

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NEVER transfer a sealed source to another person—notify the RSO if you wish to transfer your sources to a new user.

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Make a copy of the completed transfer form and keep in RedBook for documentation of transfer.

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The original must be attached to the box containing the sealed source.

Emergency Procedures

In case of earthquake or fire:

When it is safe to enter the area:

Check for damage to storage area, and then for damage to the sources themselves. If applicable, use a survey meter to check the area around the sources prior to touching them or opening storage cabinets.

If damage is observed or suspected, contact the RSO immediately. Do not touch the sources or attempt to clean up any spilled material from a broken source. Close the lab and alert all personnel to stay out to the area until the RSO can survey and clean the area.

Thank you!