Radiation Training Manual (abridged)
TABLE OF CONTENTS
- INTRODUCTION
- RADIOACTIVE MATERIAL USE AND PROCEDURES
- RADIATION PRODUCING MACHINES
- EMERGENCY PROCEDURES
- APPENDICES
Preface to the 1995 Revision
This revision of WPI's Radiation Safety Manual reflects changes made to the radiation protection program and the RHSC Rules and Regulations. These changes are the result of new regulations, license amendments, or policy changes enacted by the Radiation Health and Safeguards Committee. The layout of the manual has also been changed to make it easier to use.
The distribution of this revision coincides with the distribution of the new Radiation Safety Training and Reference Manual (TRM). The TRM presents the information necessary for users of radioactive materials and radiation producing machines to properly understand and follow the policies and procedures in this manual.
Preface
The goal of the WPI radiation safety program is to protect the user, co-workers and the general public from exposure to excessive levels of radiation and concentrations of radioactive materials. Use of ionizing radiation sources on the campus is in accordance with State and Federal regulatory requirements. Copies of WPI's radioactive materials license and pertinent State and Federal regulations are on file in the Radiation Safety Office and are available for reading to those interested.
The objective of this manual is to provide the user of ionizing radiation sources with a ready reference to regulatory agency requirements, WPI organization guidelines, and responsibilities and operating procedures relevant to the use of radioactive materials and radiation producing machines on campus. Several appendices are included to assist in radiation exposure and shielding calculations, and to describe radioisotope workplace and decontamination standards. Additional training materials are available to describe safety precautions to be used when handling specific radioisotopes, and for radiation producing machines such as x-ray diffraction machines and particle accelerators.
INTRODUCTION
Organization and Authority
Radiation Health and Safeguards Committee
The RHSC is comprised of representatives appointed by the administration. Membership is consistent with the provisions of 10 CFR 33 "Specific Domestic Licenses of Broad Scope for Byproduct Material".
The Committee is responsible for the development of uniform radiation safety policy at all Institute facilities, ensuring that the Institute complies with pertinent federal and state regulations, advising the Provost and Administrative Officers on general matters involving radiation safety, and the surveillance of Institute activities involving the use of radioactive materials and radiation producing machines.
Procurement or possession of radioactive materials, operation of machines and equipment producing ionizing radiation, and plans for construction or alteration of building facilities that may contain major sources of ionizing radiation require the approval of the Radiation Health and Safeguards Committee.
USNRC RADIOACTIVE MATERIAL LICENSE AND RADIATION CONTROL REGULATIONS
Radioactive materials are used at WPI under the authority of the United States Nuclear Regulatory Commission and a TYPE B broad scope license which delegates specific licensing authority to a technically qualified Radiation Health and Safeguards Committee. This authority includes approval of applications, issuance of notices of violation of State regulations or license provisions, and modification, suspension or revocation of approvals for health and safety considerations.
Radiation producing machines are used at WPI under the authority of the USNRC Radiation Control Regulations, and require approval by the Radiation Health and Safeguards Committee.
Responsibilities
Radiation Health and Safeguards Committee Responsibilities
The RHSC is responsible for:
- Establishing WPI radiation regulations.
- Fulfilling the requirements of the USNRC pertinent to WPI's Nuclear Reactor Facility's License.
- Satisfying USNRC requirements relevant to WPI's Byproduct Materials License.
- Providing adequate information for and dealing with the WPI community's radiological health and safeguards concerns.
- Approval and Audit of Authorized Radioisotope Users and uses of radioactive materials covered under the Byproduct Materials License.
- Evaluating and approving suggestions and recommendations for modifications to reactor equipment, to the Nuclear Reactor Facility's operating and maintenance procedures, to WPI Health Physics procedures, and to the WPI Byproduct Materials License.
- Conveying the needs of the radiation protection program to the WPI administration.
- Monitoring and regulating machines that produce ionizing radiation (i.e.: accelerators, X-ray diffraction machines, etc.).
- Evaluating and approving experiments and experimental procedures involving the Reactor and Byproduct Materials Licenses.
- Ensuring that OSHA standards pertinent to the use of ionizing radiation are not violated.
- Reviewing permits for approved use of radioactive materials on campus.
RADIATION SAFETY OFFICE
The RSO is a professional staff member of the Radiation Safety Office and is responsible for:
- Conducting inspections and reviews to verify that Authorized Radioisotope Users comply with the WPI RHSC's regulations
- Addressing emergency situations and requests for action concerning radioactive materials.
- Coordinating the film badge service and maintaining records of exposure to personnel.
- Auditing exposure and release records annually, determining if they are ALARA, and taking corrective action as necessary.
- Ordering radioactive material and maintaining a current inventory of radioisotopes at WPI.
- Supervising and coordinating the radioactive waste disposal program.
- Performing or arranging for the calibration of instruments.
- Supervising and coordinating radiological safety training (see chapter 5).
- Ensuring that records are maintained as required by federal, state, and local regulations.
- Updating the RHSC on changes to USNRC regulations that affect the use of radioisotopes at WPI.
Authorized Radioisotope Users and individuals responsible for machines producing ionizing radiation are liable for:
- All personnel who may be exposed to radiation, including visitors, personnel in neighboring laboratories, etc.
- Determining that the intent of any USNRC or State or RHSC rules is carried out in every respect, and that no regulations are violated.
- Identifying any problems in their jurisdiction arising from RHSC, USNRC, or State regulations. They shall consult with the RSO, with the RHSC, and/or with the USNRC as appropriate and shall take prompt action to see that the problems are referred to higher authority if they cannot be resolved.
- Maintaining a safe work environment in the laboratory.
- Ensuring that all participating personnel receive radiation protection training as well as any additional training that may be required (see Section 5).
- Adequately supervising all participating personnel.
- Arranging film badge service with the RSO and arranging for physical examinations where required.
- Reporting all unusual occurrences involving radiation and/or radioactive material to the RHSC.
- Submitting established written procedures of normal experimental activities to the RHSC.
- Routine surveying of his/her own operations and reporting of abnormal results to the RHSC.
- Keeping written records of the disposition of all radioisotopes acquired and reporting to the RHSC such disposition.
- Posting proper regulatory caution signs and providing adequate information for use in case of emergencies arising when he/she is not present.
- Securing the approval of the RHSC for any substantial changes in experimental and/or radiation working conditions.
- Securing the approval of the RHSC for the use of any non-exempt radioisotope quantities. No radioisotopes may be used at WPI without the knowledge of the RHSC.
- Enforcing all other safety procedures as recommended herein or by the RHSC or by the RSO.
Radiation Dose Standards
DOSE STANDARDS
Permissible occupational radiation dose levels are set by the chapter 10 part 20 of the Code of Federal Regulations (10 CFR 20). The levels are based on recommendations by the International Committee on Radiation Protection (ICRP), the National Council on Radiation Protection and Measurements (NCRP) and by federal and state regulatory agencies.
The 10 CFR 20 limits are listed in the table below.
- Dose Category
- Adult Occupational Dose Limit
- Total Effective Dose Equivalent (TEDE)
- 5 rem/year
- Total Organ Dose Equivalent (TODE)
- 50 rem/year to any individual organ or tissue except the lens of the eye
- Eye Dose Equivalent
- 15 rem/year
- Shallow Dose Equivalent
- 50 rem/year
The WPI Radiation Health and Safeguards Committee has established the general policy that planned radiation doses shall not exceed the above limits.
These dose limits are in addition to the background radiation dose or any medical radiation dose received by the worker. The average annual background radiation in the U.S. due to natural sources is approximately 300-500 millirem per year.
MINORS
Radiation doses for persons under the age of 18 are to be limited to 10 percent of the limits for adult workers listed above.
EMBRYO/FETUS DOSE
The dose limit to the embryo/fetus of a declared pregnant woman is 0.5 rem. Efforts must also be made to avoid a dose substantially higher than 0.05 rem in one month. A declared pregnant woman means a woman who has voluntarily informed the Radiation Safety Office , in writing, of her pregnancy and the estimated date of conception.
The dose to an embryo/fetus is the sum of the deep-dose equivalent to the declared pregnant woman and the dose from internally deposited radio nuclides in the embryo/fetus and in the woman.
ALARA GUIDELINE
In practice, radiation doses should be As Low As Reasonably Achievable. ALARA is a guideline meant to strike a balance between the cost of radiation protection and the health benefit derived from that protection.
It is the responsibility of everyone including radiation workers, principal investigators, radiation safety personnel and the administration to operate within the ALARA guidelines. This is achievable by outlining safety procedures for radiation environments and by monitoring the workplace environment to control contamination and minimize doses.
RADIOACTIVE MATERIAL USE AND PROCEDURES
Applications for Possession and Use
Requests to acquire and procure radioactive materials are prepared on the form "Application for Possession and Use of Radioactive Material or Equipment Producing Ionizing Radiation", available from the Radiation Safety Office. Requests are submitted to th e RHSC for approval via the RSO, and must be completed in sufficient detail so that the Committee can evaluate the request prior to approval.
You should submit an experiment protocol or describe in your application those experimental procedures or actions that may affect or cause the inadvertent release or ingestion/inhalation of radioactive material. You should also name any hazardous chemicals and compounds that will be used. Material Safety Data sheets can be provided as guides for their safe use.
Approved applications are valid indefinitely, but each year must be reviewed and current inventory verified. Applicants will arrange with Radiation Safety for the disposal or transfer of any remaining radioactive material on hand, at the completion of work involving radioisotopes.
In order to expedite the approval of most applications, the Committee has designated the RSO in to authorize and approve applications considered to be routine in nature. The following specific uses are considered to be major in nature and will require re view and approval of the entire Committee.
- Applications for acquisition of hazard class I isotopes in quantities greater than 100 microcuries and hazard class II isotopes greater than 1 millicurie.
- Applications for experiments or projects which involve substantial airborne hazards arising from gases, fine powders, or aerosols.
- Applications for new installations or for major modifications to existing facilities involving the use of ionizing radiation sources.
- Other applications for uses which the RSO feels should be brought to the attention of the full Committee.
Note: It will generally take a minimum of two to four weeks to arrange for the Committee to meet for review of applications in the categories above(most likely the application will have to wait for the next quarterly meeting). Therefore, such application s should be submitted well in advance of the planned starting date.
Amendments
A request for amendment to an approved application is submitted as above. Amendment requests may be made only for changes in quantities of an isotope, addition or deletion of users, or changes in location of use. Requests for new projects or uses, or different isotopes must be submitted on a new application.
Receipt, Shipment, and Delivery
No radioactive material is to be brought onto or shipped from the campus without the prior approval of the RSO. If materials are to be hand carried onto or from the campus, authorization by the RSO is required, and when radioactive materials are to be shipped by common carrier, the packaging and labeling must be approved and certified by Radiation Safety personnel.
All incoming radioactive materials are delivered to the Chemistry Stockroom where they are checked for damage and then picked up by a representative of the Radiation Safety Office and taken to the reactor facility to be checked for contamination, placed i n inventory and delivered to the authorized user. Deliveries are usually made once a day in the afternoon. If you have special time requirements, inform the Radiation Safety Office when you place your order. An attempt will be made to make a special delivery or ar range for you to pick up you order early. Certain large, heavily shielded orders may be delivered directly to the purchaser, but must be opened under the supervision of Radiation Safety Office personnel.
Personnel Monitoring
The Radiation Health and Safeguards Committee has established the general policy that all persons listed on an application for use of radioactive materials or radiation machines are required to be on the WPI dosimetry program. External dosimeters are used to detect and measure radiation exposure to the whole body, skin and extremities. A bioassay (urinalysis) program detects internal radiation exposure from radio nuclides that may have been incorporated in body tissues or fluids. Thyroid assays for radioiodine are done using an external detector. External and internal dosimetry requirements are established at the time of approval of each application or amendment.
EXTERNAL DOSIMETRY
The film badge is WPI's basic dosimeter and its use is required for all authorized users of radioactive materials and radiation machines. The HP may exempt certain special cases where a film badge would not provide any useful exposure information, such as persons using only H-3, S-35, C-14, or certain sources installed permanently in equipment, or small sealed sources.
Use of a finger dosimeter will usually be required for operations involving the regular handling of millicurie or greater quantities of gamma emitters or high energy beta emitters (e.g. P-32, Sr-90).
The HP may require that special dosimeters such as pocket ion chambers be issued for use in High Radiation Areas (greater than 100mR/hr) or that certain areas be posted with environmental dosimeters, or that alarmed electronic dosimeters be installed or u sed for certain conditions.
BIOASSAY PROGRAM
All persons authorized to use unsealed sources of radioactive materials in activities greater than levels set by the RHSC will be included in WPI's bioassay program. Questionnaires are sent to users periodically to determine whether or not a bioassay is required.
Persons working with or exposed to 100 millicuries or more of H-3 at one time are required to notify the safety office and submit a urine specimen after the experiment or use and at succeeding intervals if necessary until background levels are reached.
Persons who work with 1 millicurie or more of volatile or dispersible radio iodine or 10 millicuries or more of non-volatile radio iodine must call radiation safety after the use to schedule a thyroid check.
Policies and Procedures for Radioisotope Use in the Laboratory
POSTING AND MARKING OF LABORATORIES, AREAS, AND EQUIPMENT
Each laboratory or area where radioactive materials are used or stored must be posted at the entrance with a CAUTION RADIOACTIVE MATERIALS sign. The sign must include the name and home phone number of the responsible Applicant. Entry and area warning sign s are to be posted and removed only by Radiation Safety personnel.
Refrigerators, freezers, and other 'in lab' storage areas, and containers in which materials are stored or transported must have a visible label with the radiation caution symbol and the words CAUTION RADIOACTIVE MATERIALS. The label should also state the kind and quantity of material in the container. RADIOACTIVE MATERIAL labels should be removed from containers if they are empty and not contaminated.
Areas in the laboratory where radiation levels might expose a person to 5 millirem in any one hour, or 100 millirem in 5 consecutive days must be posted with the sign CAUTION RADIATION AREA. Equipment doors and covers need not be posted if radiation level s are high only when doors are open.
Laboratory equipment (flasks, beakers, centrifuges) containing radioactive materials need not be marked so long as the user is present and the material is in a designated and marked radioactive material work area. Unattended and contaminated equipment and tools must be marked with warning tape or labels.
Radiation Safety personnel may post areas and equipment to indicate significant levels of contamination found during surveys. These signs are to be removed only when the article or area has been satisfactorily decontaminated.
Radiation Safety personnel may specify additional posting to control access or ensure safe operations.
PROTECTIVE CLOTHING AND LABORATORY SAFETY PRECAUTIONS
Each approved application lists the type of workplace and protective equipment required for use of radioisotopes. Appendix 2, Workplace Standards for Operations with Unsealed Radioactive Materials should be consulted. In addition to t he workplace requirements the following are always applicable:
- A lab coat or plastic apron and gloves should always be worn whenever any unsealed sources of radioactive material are handled (even in tracer amounts). TLD badges and ring dosimeters should always be worn.
- Pipetting radioactive solutions by mouth is extremely dangerous and must not be done under any circumstances. Use a safety pipette, or other suitable means.
- Do not smoke, eat, store food, or apply cosmetics in any laboratory where unsealed radioactive materials are used or stored.
- To avoid spills, use metal or plastic outer trays or beakers to carry liquid radioactive materials from one lab to another.
- Do not work with unsealed radioactive materials if you have open cuts, sores, etc., on exposed skin areas, even if bandaged.
- After handling radioactive materials, be sure to wash hands thoroughly before handling food products, tobacco, etc.
SURVEY METERS
Applicants shall provide radiation survey meters for use in laboratories and work areas (except for those areas where H-3 is used exclusively in a non- volatile form). The meter must have a detector "window" capable of detecting the radiation from material or source being used. For most operations involving pure beta emitters and low energy gamma emitters, a 1.5-2.0 mg/cm2 window is needed.
Radiation Safety will calibrate survey meters, check for proper operation, and replace weak or defective batteries at six month intervals. It is the Applicant's responsibility to make the meters available and to obtain any other servicing or repairs to ke ep meters operational.
SURVEY OF WORK AREAS
Users of radioactive materials are required to survey their work areas (hoods, bench tops, sinks, floors, etc.) after each experiment and at any time there is a reason to suspect a spill or contamination incident.
The Radiation Safety Office will survey all laboratories on a regular basis.
Under certain conditions, laboratories are required to keep written documentation of contamination surveys.
Required surveys are listed in the table below.
- Routine survey
- Performed by the user after each experiment and at any time there is reason to suspect a spill or contamination incident. These surveys shall be documented using Health Physics Form 8. These forms shall be kept in the laboratory until the form is full . The completed form will then be kept on permanent record in the Radiation Safety Office.
- Monthly survey
- Performed by the a representative of the Radiation Safety Office on a monthly basis or whenever a contamination incident is suspected. Records of these surveys will be kept on file in the Radiation Safety Office. Copies will be sent to the Principal Investigator associated with each lab.
RADIOACTIVE NUCLEIC ACIDS AND DERIVATIVES
Experiments involving the use of radioactive nucleic acids and radioactive nucleic acid derivatives present a special hazard in that some of these compounds may become incorporated in the genetic material of the body cells. The following procedures have been adopted by the Radiation Health and Safeguards Committee for the use by all workers who use such material.
Special care should be used during all experiments which involve the use of radioactive nucleic acids, radioactive nucleic acid derivatives, or substances in which these compounds have been incorporated.
When the quantity of a radioactive isotope used in any one experiment is less than 200 uCi, the following precautions suffice:
- The experiment should be done only in a designated area within the laboratory. This area should be physically separated from other work areas if at all possible. The bench top should always be covered with absorbent paper.
- Rubber or plastic gloves and lab coats should be worn at all times during the handling of the radioactive materials.
When the quantity of a radioactive isotope used in any one experiment exceeds 200 uCi, experimental manipulations must be carried out in a fume hood. Radiation Safety should be consulted concerning the adequacy of fume hoods used for this purpose.
RADIOACTIVE MATERIAL CONTROL
Applicants and users must ensure that radioactive materials and sources are used only as described on the application, and must not be loaned or transferred to persons not named on the application without prior approval of the Radiation Health and Safeguards Committee. The loss, disappearance or damage of radioactive materials and radiation sources must be reported to the RSO immediately.
The Radiation Safety Office maintains a campus inventory record of all incoming and outgoing shipments of radioactive materials including disposal of radioactive waste. This record is updated at least quarterly.
Each Applicant should report annually at authorization review time the amount of material on hand for each application.
SHIELDING OF SOURCES AND MATERIALS
When not in use, radioactive sources and stock solutions in the laboratory shall be stored or shielded so that radiation levels in occupied areas will not expose persons unnecessarily.
Appropriate shielding, tool extension, etc. should be used when handling millicurie and greater quantities of radioactive materials. Hydrogen-3 (tritium), carbon-14, sulfur-35, and similar low energy beta emitters are not usually external radiation hazard s and do not require shielding or special handling. Gamma emitters and high energy beta emitters (e.g. P-32, Ru-106, Sr-90) may present a significant external radiation hazard. The energetic beta emitters should be shielded first with lucite and then with lead, if necessary, to minimize the generation of penetrating Bremsstrahlung radiation.
AEROSOLS, DUSTS, GASES
Procedures involving aerosols, dusts, volatile or respirable material must be conducted in hoods or suitable closed systems approved by the Radiation Safety Office. Where practical, suitable traps should be used to minimize environmental releases.
Use of Radioactive Materials in Animals
Approval to use radioactive materials in animals requires authorization from the Radiation Health and Safeguards Committee. Specific Radiation Health and Safeguards Committee approval requirements will depend on the protocol, the isotope(s) used, levels of activity, frequency of use, number of animals, disposal issues, and size of the animals.
Radioactive Waste
Radioactive waste may only be disposed of by calling Radiation Safety for pick up. No radioactive waste is to be disposed of in ordinary trash receptacles. No liquid waste may be disposed of in drains or other sewer openings without prior approval by th e RSO laboratory personnel.
MIXED HAZARDOUS/RADIOACTIVE WASTE
Radioactive waste containing any hazardous chemicals requires special handling. Radiation Safety must be consulted before any such waste is generated.
SOLID WASTE
- Place solid waste in containers approved by the Radiation Safety Office. Be sure to use the container appropriate for the radionuclide in the waste.
- Indicate Principal Investigator, nuclide, and estimated activity on the tag attached to the container.
- When container is nearly full, call Radiation Safety for pick up and supply the following information:
- Principal Investigator
- Location of container
- Contents of container
Note: Do not wait until can is no storage space is left to call in.
SHARPS
Contaminated sharps (e.g. needles, razor blades) should be kept in a separate, puncture resistant container. This container will be picked up on request.
STOCK VIALS
Stock vials containing high activities should be kept in a separate container. This container will be picked up on request.
LIQUID WASTE
- Pour liquid waste into containers approved by the Radiation Safety Office. Be sure to use the container appropriate for the radionuclide in the waste. Liquid radioactive waste includes the radioactive material and the first rinse of its experimental container.
- Indicate Principal Investigator, nuclide, and estimated activity on the tag attached to the container.
- When container is nearly full, call Safety for pick up and supply the following information:
- Principal Investigator
- Location of container
- Contents of container
Note: Do not fill containers completely. Do not wait until container is full to call in.
SCINTILLATION VIALS
- Filled scintillation vials must be capped and in their boxes or trays. Loose vials will not be accepted.
- Call the Radiation Safety Office and provide the following information:
- Principal Investigator
- Number of trays
- Location
- Nuclides and estimated activity of each
SCINTILLATION FLUID
- Scintillation vials may be emptied into containers approved by Radiation Safety. This work should be done in an approved fume hood to prevent exposure to solvent vapors.
- Completely empty and uncapped vials may be disposed of as ordinary trash, providing labels and markings which indicate the presence of radioactive materials are removed.
- When container is nearly full, call Radiation Safety for pick up and supply the following information:
- Principal Investigator
- Location of container
- Nuclides and estimated activity of each
Note: Do not fill containers completely. Do not wait until container is full to call in.
Radiation Safety will pick up waste within three working days after a request is called in.
Radioactive Material Use Permit Termination and Non-compliance Policy
USE PERMIT TERMINATION
At termination of a permit, all unused radioactive materials must be accounted for and turned over to the Radiation Safety Office for storage or disposal. Materials may be transferred to another authorized user following health physics approval. Users w ill be held responsible for all disposal fees resulting from their use of the material.
Failure to follow RHSC and NRC regulations will result in of the permit. To reactivate a canceled permit, a new request must be submitted for committee review.
NON-COMPLIANCE POLICY
The following items of non-compliance will be brought to the attention of the RHSC. The RSO may recommend review by the full committee.
- Willful violation of university or state regulations regarding the use of radioactive materials or radiation producing machines.
- Loss of or inability to account for radioactive sources and materials in your possession.
- Repeated finding of mid or high level contamination.
- Repeated significant exposures or exposures exceeding WPI quarterly administrative limits in any month.
- Negligent use of radioactive materials endangering the safety of persons or the environment.
- Use of radioactive materials not authorized by the permit.
Depending on the severity of the incident, the committee may issue a formal warning, or revoke or suspend a person's use approval or the entire use permit.
RADIATION PRODUCING MACHINES
General
DEFINITIONS
A radiation producing machine is any device capable of producing ionizing radiation when the associated control devices are operated, except devices which produce radiation only by the use of radioactive material.
An enclosed system is a radiation producing machine which satisfies the requirement that all areas with exposure rates greater than 0.25 mR/hr are enclosed within an interlocked barrier. All others are considered open systems.
X-ray diffraction and radiography units, particle accelerators, electron microscopes, and high voltage rectifiers operating above 10 kV all fall into the category of radiation producing machines.
REGULATION
Use of radiation producing machines is regulated by the State. A copy of the Mass. Radiation Control Regulations is available for review in the Radiation Safety Office. WPI's policies for the use of radiation producing machines are designed to meet the applicable requirements of the state regulations and to ensure the safety of users and other personnel.
REGISTRATION
Radiation producing machines must be registered with the State and a registration fee paid. Registration will be in the name of the Institute, with the Radiation Safety Office as point of contact. The Radiation Safety Office must be notified of the acquisition, transfer, or disposal of any radiation producing machine. Some machines, such as electron microscopes, may be exempt from registration. The Radiation Safety Office will make that determination based on current state guidelines.
APPLICATION FOR USE
Faculty members who wish to operate a radiation producing machine must submit an Application for Use of Radiation Producing Machine form to the Radiation Health and Safeguards Committee (RHSC) via the Radiation Safety Officer (RSO).
Each application must be completed in sufficient detail for RHSC evaluation. Applications must include a description of the machine (including maximum operating parameters), description of proposed use, and for machines operating above 100 kV, a description of the facility.
Principal Investigators submitting an application for a new accelerator facility or major changes to an existing facility must work closely with the Radiation Safety Office and the RHSC during the application (or amendment) submission and review process.
Accelerators, diagnostic or radiographic x-ray machines, or other radiation producing machines which may present special hazards require operating conditions beyond those listed in this chapter.
Applications for permits and a guide for completing them are available from the Radiation Safety Office. The Radiation Safety staff will assist applicants in completing forms.
AMENDMENT TO PERMIT
A request for amendment to an approved application is submitted as above on a Request for Amendment to Permit for Use of Radiation Producing Machine form available from the Radiation Safety Office. Amendment request may be made for the following changes:
- Location of machine (<100 kV)
- Change in facility design (>100 kV)
- Change in proposed use
PERMIT AUTHORIZATION
All applications for use of radiation producing machines are reviewed by the RHSC or the sub-committee. Upon approval, a numbered permit is issued, listing any special conditions specified by the RHSC.
Most applications and amendment requests are approved by the sub-committee. The following require full committee approval:
- Applications for the use of an accelerator.
- Applications for the use of radiographic x-ray units operating above 100 kV which have not been previously approved for operation.
- Applications or amendments which the RSO feels should be brought to the attention of the full committee.
Policies and Procedures for Use of Radiation Producing Machines
AUTHORIZED USERS
Principal Investigators are responsible for ensuring that only authorized users are allowed to operate their machines. Authorized users are those individuals listed on the original application or added using the New Personnel Form.
TRAINING REQUIREMENTS
New personnel must be trained by the Principal Investigator (or an experienced qualified operator designated by the P.I.) and must satisfactorily demonstrate knowledge of operating and safety procedures before independently operating a radiation producing machine.
Depending on prior experience and the type of machine to be operated, new personnel may be required to attend an orientation with a Health Physicist in the Radiation Safety Office and/or complete a short written test to demonstrate knowledge of operating and safety procedures.
POSTING
A sign bearing the radiation symbol and the words CAUTION X-RAYS must be posted at the entrance to each laboratory containing a radiation producing machine. The sign must include the name and after hours phone number of the Principal Investigator or designee.
A label bearing the words CAUTION THIS EQUIPMENT PRODUCES RADIATION WHEN ENERGIZED (or similar wording) must be affixed to the control device of each machine.
A label bearing the words CAUTION HIGH INTENSITY X-RAY BEAM (or similar wording) must be affixed on or near the tube of an x-ray unit.
An X-RAYS ON warning light, labeled as to its meaning, shall be located on or near an x-ray tube to indicate when x-rays are being produced.
ACCESS CONTROL
Key control must be maintained for each machine. For older machines which do not have a keyed control device, this requirement may be fulfilled by controlling access to the laboratory.
While any open system is in operation, an operator must be present or the laboratory must be kept locked.
OPERATING PROCEDURES
Operating procedures for each machine must be available near the machine. For open systems, these procedures must specifically include:
- means to control and limit exposures to individuals, including controlling access to the area.
- the use of radiation survey instruments and film badges.
SURVEYS
For open systems, the Principal Investigator must provide a radiation survey meter to indicate the presence of unwanted radiation and to trace the origin of leaks. The recommended instrument is a Geiger-Mueller survey meter with a thin window probe.
After a change in experimental set-up and before energizing the machine, the operator must visually inspect ports, cameras, shielding, etc. After the machine is energized, a radiation survey should be performed to check for scattered or leakage radiation.
UNUSED PORTS
All unused x-ray ports must be permanently blocked or be interlocked so that x-ray production is stopped if the port is opened. Material used to block unused ports must be of sufficient density and thickness to attenuate the primary beam to acceptable levels.
SHIELDING
Protective barriers and/or shielding must be used in open x-ray systems to ensure exposure rates in accessible areas are less than 2 mR/hr at 5 cm from any exterior surface. It is important to avoid cracks and gaps in the shielding.
LOG BOOK
For open systems, a log book must be kept which records the following information:
- operator
- date
- voltage
- current
- exposure time
- radiation survey results
DOSIMETRY
Dosimetry requirements will be established by the Radiation Safety Office upon a review of each facility.
In general, users of electron microscopes or other enclosed systems will not be issued dosimeters.
Users of accelerators, radiographic units, or open system x-ray diffraction units will be issued a personnel dosimeter (TLD badge). This dosimeter should be worn while in the facility when the machine is in operation. The film badge will only measure scattered radiation; it will not indicate personnel dose from exposure to the primary beam.
Radiation Safety may post dosimeters at various locations in the facility. These dosimeters should not be moved by laboratory personnel.
RADIATION SAFETY SURVEYS
The Radiation Safety Office performs inspections of radiation producing machines when first installed, at yearly intervals, and whenever significant changes to the machine, facility, or operating procedures are made.
EMERGENCY PROCEDURES
INTRODUCTION
During the course of routine operations, radioactive material may be spilled resulting in contamination of personnel or lab equipment and areas. Correct action taken during such an incident can prevent unnecessary exposure to personnel and further spread of contamination.
GENERAL PROCEDURES
Medical attention takes precedence over radiological or other concerns in the case of a serious injury. Inform medical personnel if there is the possibility of contamination.
Do not risk external or internal exposure to save equipment or an experiment. An exception to this should only be made at the direction of a person qualified to evaluate the hazards involved.
Take all reasonable precautions to limit the spread of the radioactive contamination.
- Limit access to the area.
- Turn off ventilation system, if possible.
- Prevent spread of liquid or powdered contaminates.
SERIOUS INJURY INVOLVING RADIOACTIVE MATERIAL
- Dial extension x5555 and request paramedics. Tell operator that it is also a radiation emergency and have him/her notify the Radiation Safety Officer or his/her alternate. When paramedics arrive, inform them of the possibility of radioactive contamination.
- Determine and record the radio nuclide and activity involved and the chemical form.
- Follow steps for a major or minor spill as appropriate.
MAJOR SPILL
A spill is considered major if it results in any of the following:
- Internal radiation exposure to personnel (inhalation/ingestion of radioactive material).
- Excessive external radiation exposure to or contamination of personnel.
- Contamination of large areas.
- Considerable delay in work.
- Notify personnel not involved in the spill to vacate the laboratory. Prevent other personnel from entering the contaminated area.
- Monitor personnel for contamination.
- Remove contaminated clothing. If skin is contaminated, flush thoroughly with water and wash with mild soap.
- Confine movement of all potentially contaminated personnel to prevent further spread of contamination.
- Cover a liquid spill with absorbent paper or pads. Dampen dry powders, being careful not to spread contamination. Use oil if material is water reactive. Do not attempt to clean up the spill.
- Notify Radiation Safety Office(x5688). If after working hours, dial x5555 and instruct officer to contact the Radiation Safety Officer or his alternate. Also notify the laboratory supervisor or Principal Investigator.
- If possible, turn off fans or ventilation that might spread vapors or dust.
- Determine and record the radio nuclide and activity involved, the chemical form, and personnel involved.
- Assist Radiation Safety Office personnel in evaluation and decontamination.
MINOR SPILL
A spill can generally be considered minor if it contaminates small areas or equipment and results in:
- No external or internal contamination of personnel.
- No excessive external radiation exposure to personnel.
- No serious delay in work.
- Notify personnel in the area that a spill has occurred.
- Monitor personnel leaving the area and remove any contaminated clothing.
- Cover a liquid spill with absorbent paper or pads. Dampen dry powders, being careful not to spread contamination. Use oil if material is water reactive.
- Call the Radiation Safety Office(x5688) if assistance is needed.
- Plan the decontamination procedure before proceeding. Keep in mind these points:
- Limit personnel to a minimum.
- Wear appropriate protective clothing.
- Dispose of all contaminated material as radioactive waste.
- Use appropriate survey instruments. Perform wipe tests if necessary.
- After decontamination, check all areas around the spill and all personnel for contamination. Be sure to check hands and shoes.
EMERGENCIES INVOLVING RADIATION PRODUCING MACHINES
In the event of an accident or unusual incident involving a radiation producing machine:
- Turn off the machine. If possible, also unplug or shut off the circuit breaker for the machine.
- If there is a serious injury or fire, call x5555 and request paramedics or the fire department.
- Notify the Radiation Safety Office (x5688). If after working hours, call x5555 and have the operator contact a Radiation Safety Office representative.
- Notify the laboratory supervisor or Principal Investigator.
- Record information about the incident (e.g. operating voltage and current, exposure time, distance from radiation source).
APPENDICES
Classification of Radio nuclides According to Relative Hazard Potential
Class 1 (very high toxicity)
Sr-90 + Y-90, Pb-210 + Bi-210, Po-210, At-211, Ra-226, Ac-227, Th-228, Th-229, Th-230, Th-231, U-233, Pu-238, Pu-239, Am-241, Cm-242, Cf-252, other transuranicisotopes.
Class 2 (high toxicity)
Ca-45, Ca-47, Fe-59, Co-60, Sr-85, Sr-89, Y-91, Ru-106 + Rh-106, Cd-109, Cd-115, I-125, I-131, Ba-140 + La-140, Ce-144 + Pr-144, Sm-151, Eu-152, Eu-154, Tm-170, Hg-203, Bi-207, Th-232, natural thorium, natural uranium.
Class 3 (moderate toxicity)
Na-22, Na-24, P-32, P-33, S-35, Cl-36, K-42, Sc-46, Sc-47, Sc-48, V-48, Cr-51, Mn-54, Mn-56, Fe-55, Co-57, Co-58, Ni-59, Ni-63, Cu-64, Cu-67, Zn-65, Ga-67, Ga-68, Ga-72, As-74, As-76, Br-82, Kr-85, Rb-84, Rb-86, Y-90, Zr-95 + Nb-95, Nb-95, Mo-99, Tc-99, R h-105, Pd-103 + Rh-103, Ag-105, Ag-111, Sn-113, Te-127, Te-129, I-132, Xe-133, Cs-137 + Ba-137, La-140, Pr-143, Pm-147, Ho-166, Lu-177, Ta-182, W-181, Re-183, Ir-190, Ir-192, Pt-191, Pt-193, Au-196, Au-198, Au-199, TI-200, TI-202, TI-204, Pb-203, Hg-197.< p>
Class 4 (slight toxicity)
H-3, Be-7, C-14, F-18, Cr-51, Ge-68 Ge-71, Sr-87m, Tc-99m, In-111, TI-201, U-235, U-238.
This classification is used as part of the evaluation of an application to determine the type of laboratory or workplace standards required. The toxicity ratings are extracted from various published data, but may have been shifted up or down when in the professional judgment of the health physicist local conditions indicate the need.
Workplace Standards for Operations with Unsealed Radioactive Materials
Sorry, this appendix has not yet been entered into this document.
Contamination Limits in the Workplace and Decontamination Requirements
Guidelines for Radioactive Surface Contamination
(From Health Physics Society draft standard ANSI N13.12 1987
| Group No. | Group Description | Total Activity Removable + Fixed dpm/100cm2 |
|---|---|---|
| (1) | All a emitters (except those in (4)) plus 210Pb (210Po) and 228Ra (228Th) | 20 |
| (2) | 90Sr, 125I, 126I, 129I, 131I | 200 |
| (3) | All b, g -emitters not in groups (1), (2) or (4) | 1,000 |
| (4) | Uranium (natural, enriched < 10%), Thorium (natural) | 200 |
Decontamination
(1) Uncontrolled Area: An area in which no radioactive materials are being used or stored, and which is available for general use.
(2) Low-level contamination: Minor contamination which is not considered to be a health hazard to the occupants of the laboratory.
- Decontamination action: (a) Radiation safety will report findings to the lab occupants, (b) Lab occupants should decontaminate promptly, but may decide whether the contamination can be tolerated in the particular work situation.
(3) Mid-level contamination: A significant level of contamination that may be a health hazard to those exposed if allowed to continue.
- Decontamination action: (a) Radiation Safety will notify occupants that the hazard exists, and label equipment and areas with warning tape. (b) Applicant/occupants must see that decontamination is completed promptly and no later than one week. (c) Radiation Safety will check when notified of completion but no later than one week. A "Report of Unsatisfactory Conditions" will be sent to Applicant if work is not completed in allotted time.
(4) High-level contamination: A potential health hazard if allowed to continue. The degree of hazard depends on such factors as the type of radiation, chemical or physical form, external dose rate, etc. The professional judgment of the HP will play an essential part in determining the degree of hazard.
- Decontamination action: (a) This level of contamination requires immediate action. Depending on the extent of the contamination, further use may be suspended until decontamination is completed. (b) A "Report of Unsatisfactory Conditions" will be sent to the Applicant and DRSO if not decontaminated immediately. In this situation the Applicant will be required to report to the RHSC stating the reason for the incident and actions taken to minimize the risk of a repeat.