Section 7: Working with Radioactive Materials and Devices

All radiation sources must be stored in a secure location (restricted access, minimum fire hazard, approved ventilation, sufficient shielding, and locked), labeled, and the location posted with a “Caution Radioactive Material” or “Caution Radiation Emitting Device” sign. The DMPRS will provide the laboratory with the proper signs and documentation to ensure compliance with the posting requirements of 105 CMR 120.

1. Source description;
2. Original activity or radiation emission rate and date;
3. Record of usage and estimated remaining activity;
4. Physical location; and
5. Disposition of material and date.

The SciShield radioisotope inventory function allows authorized users to maintain and record the inventory requirements listed above. Also, the Radioactive Material Use Log is recommended for recording the above information and may be obtained from the DMPRS website.

Each individual radiation source (or container) shall be labeled with an identification tag clearly indicating the date, radionuclide, volume, and activity. Labels are available from the DMPRS. All tags or labels must be removed/replaced/defaced when the information on them is no longer current. Contact the DMPRS for questions on the labeling of radiation sources.

Regulations require the licensee to provide radiation dosimetry (also called a radiation badge or ring) to any individual that may exceed ten percent of the applicable annual occupational dose limit (see Occupational Radiation Exposure Limits, Section 5). Operations in the laboratory and hospital were evaluated for the potential to exceed ten percent of the dose limit. Operations that Section 7 require a dosimeter were identified and the wearing of dosimeter by these individuals is considered mandatory. Operations that do not require a dosimeter were also identified and the wearing of dosimetry by these individuals is considered “optional,” i.e., the individual may participate in the dosimetry program and can elect to wear a dosimeter if they so choose and must fully cooperate with the periodic change out of the dosimeter. Any

Laboratory Operations

Most individuals working in research laboratories at BU/BMC will not require the use of radiation dosimetry, but may be provided dosimetry under specific circumstances as determined by the RSO. Radioisotope Users working with one millicurie or greater of a gamma or positron emitter, or high-energy beta emitter (e.g. P-32), in any one quarter will be issued dosimetry.

Hospital Operations

Individuals working directly with radiation sources, such as nuclear medicine isotopes, fluoroscopy, radiography, etc. do have the potential for approaching and exceeding ten percent of the applicable occupational dose limits. Therefore, individuals working directly with radiation sources in the hospital environment will require radiation dosimetry. Hospital employees that may inadvertently be exposed to radiation, such as through incidental contact with patients injected with nuclear medicine isotopes, or standing in the vicinity while a portable X-ray machine is used, receive very little exposure and do not require monitoring for radiation exposure. These individuals may be provided with dosimetry upon request. Note, there may be special cases when such individuals will require radiation monitoring. The DMPRS maintains awareness of radiation source use and will evaluate the need for monitoring in special cases.

Radioactive contamination control is practiced through the proper handling of radioactive material, use of adequate protective clothing, and use of sealed containers for transfer and storage of such material. The following steps will help to control the creation and spread of contamination:

1. All areas in which radioactive material is used or stored will be posted as a “Radioactive Material Use” area.
2. Required protective clothing will be specified.
3. Wipe tests will be taken at routine intervals to evaluate the level of contamination.
4. Volatile radioactive compounds will be stored in sealed containers and vented prior to use in approved filtered hoods.
5. Eating and drinking is prohibited in all laboratories.
6. Air samples will be taken if significant airborne contamination is anticipated.
7. Leak tests will be performed on sealed sources.

Controlled areas will be established for controlling movement of radioisotopes and personnel. Segregating these areas will minimize the potential for accidental contamination and unnecessary radiation exposure. Every individual working or visiting such areas should observe signs and directions indicating actions to be taken in a specified area.

Controlled areas are designated as follows:

1. A controlled area is an area where access is controlled for purposes of personnel protection. State and federal regulations place the following restrictions on elevated radiation areas:
   
   1. Radiation Area: A radiation area is defined as any area, accessible to personnel, in which radiation levels could result in an individual receiving a dose equivalent in excess of 5 millirem at a distance of 30 cm in one hour from a radiation source. These areas must be posted.
   2. High Radiation Area: This area is defined as any area, accessible to personnel when radiation levels could result in individuals receiving a dose equivalent in excess of 100 millirem in one hour at 30 cm from the radiation source or boundary. High Radiation Areas require access control measures to be instituted.
2. Contamination Area — an area where controlled access is maintained for the purpose of contamination control. Persons should not enter such an area without authorization and proper personnel protection. The following defines a contamination area:

Surveys shall include a contamination survey and, if appropriate, an area radiation survey. Laboratories which use radioisotopes which do not pose an external radiation hazard (such as C-14 or H-3) are not required to perform radiation area surveys but are required to perform contamination surveys. Radiation users who wish to review proper radiation survey techniques may consult the guide on the DMPRS website or may contact a member of the DMPRS.

The following is a list of recommended laboratory radiation surveys:

1. Radiation and contamination surveys (as applicable) when a radioisotope is used, especially immediately following the transfer of radioactive materials from stock solutions.
2. After each experimental run if there is a possibility of a change in radiation levels or contamination.
3. After a radioactive material spill.

Frequency of laboratory surveys will depend on the status of the radioisotope permit and hazards classification of the isotopes used and possession limits as outlined in the table below.

*Survey frequency dictated by regulation.

Radionuclides must be stored only in designated storage areas/containers, which are approved by the DMPRS. These areas and containers must be secured when unattended in a manner which prevents access and/or removal by unauthorized and untrained personnel. In practice, if access to the laboratory or storage area is limited only to radioisotope users (no ancillary or clerical staff has access), it is considered a sufficient security measure. If this is not possible, secure and lockable security freezers are acceptable. If neither of the previously mentioned security measures is available, affixed security boxes are a widely used solution throughout BU/BMC. The security of irradiators is addressed in Public Safety procedures and policies.

Proper hazard communication is an integral part of the radiation safety program. All entryways to spaces permitted to use radioactive materials must display a radioactive materials sign on the posted BU HAZCOM sign. In addition, all entry ways must have emergency contact numbers visible detailing DMPRS contact information during business hours and Control Center contact information for 24 hour support.

Signs and labels are available from the DMPRS and must only be used to correctly communicate the presence of radioactive material, radiation hazards, or airborne radioactive contamination.

Depending on the nature of the area or laboratory the sign must bear the words:

• Caution Radioactive Material ‑ This sign is required in areas where radioactive materials are used or stored.

1. The permit holder shall:
   • Keep an inventory of radioisotopes, on paper and in SciShield; and
   • Keep a record of all waste disposals of radioactive material.
2. The DMPRS shall maintain:
   1. Up-to-date inventories of all radioisotopes;
   2. Radiation surveys and monitoring records of a general and special nature;
   3. Records of all incidents (spills, releases, contamination problems) involving radiation sources;
   4. Leak test data on all radiation sources;
   5. Personnel monitoring records;
   6. Instrument calibration records;
   7. Waste disposal records;
   8. Licensing data;
   9. Emergency equipment lists;
   10. Minutes of RSC and subcommittee meetings;
   11. Applications for authorization to use radiation sources;
   12. Copies of authorizations and a list of all radioisotope users; and
   13. Decommissioning files in accordance with state regulations.

1. All radioactive material containers (including waste containers) must be removed.
2. All equipment associated with the processing, handling and storing of radioactive material must be surveyed on all accessible surface areas to ensure radioactive materials are below the limits defined in APPENDIX IV: BOSTON UNIVERSITY / BOSTON MEDICAL CENTER
3. Equipment that has the potential to become internally contaminated must be either surveyed to verify the absence of radioactivity or be disposed of as radioactively contaminated. Special consideration must be given for plumbing, air handling, and fume hoods.