Radioactive Materials Safety Manual
2408 Wanda Daley Drive Ames, Iowa 50011-3602
(515) 294-5359 | www.ehs.iastate.edu
Copyright ©
Reviewed 2018 Radioactive Materials
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Directory of Service and Emergency Providers
Services
Environmental Health and Safety 2408 Wanda Daley Drive | (515) 294-5359
Iowa State University Occupational Medicine Department G11 Technical and Administrative Services Facility (TASF), 2408 Pammel Drive | (515) 294-2056
McFarland Clinic PC, Occupational Medicine 1018 Duff Avenue | (515) 239-4496
Thielen Student Health Center 2647 Union Drive | (515) 294-5801
Emergency
Emergency - Ambulance, Fire, Police 911
Department of Public Safety/ Iowa State University Police Armory, 2519 Osborn Drive | (515) 294-4428
Mary Greeley Medical Center 1111 Duff Avenue | (515) 239-2011
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Table of Contents
Directory of Service and Emergency Providers 3 Table of Acronoyms 8 A. Introduction 9 B. Regulatory Requirements 10 University Policy 10
C. Administrative Controls 11 Environmental Health and Safety 11
Radiation Safety Committee 11
Radiation Safety Officer 11
University Compliance Committees 12
Animals - Institutional Animal Care and Use Committee (IACUC) 12
Biohazards - Institutional Biosafety Committee (IBC) 12
Humans - Institutional Review Board (IRB) 12
Radiation - Radiation Safety Committee (RSC) 12
D. Process Planning 13 Authorization Process 13
Personnel Information 13
Facility Description 14
Project Description 14
Research Centers 15
Review and Approval of Application 15
Summary of the Radiation Authorization Application, Review and Approval Process 16
Radiation Authorization Amendments 16
Adding Authorized Personnel 16
Approval in Concept 17
Authorization Termination and Laboratory Closure 17
E. Training Requirements 18
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Radioactive Material Users 19
Awareness Training for Laboratory Personnel 19
Service Personnel Working in a Radiation Laboratory 19
Minors Visiting or Completing Work in a Radiation Laboratory 20
Laboratory Specific Training 20
F. Responsibilities 21 Responsibilities of the Principal Investigator 21
Responsibilities of the Authorized Personnel 22
G. Obtaining Radioactive Material 23 Ordering Radioactive Material 23
Radioactive Material Ordering Procedures: 23
Receipt and Delivery of Radioactive Material 24
Receipt of Free/Gifted/Evaluation Materials and Devices 25
H. Security, Storage, Transfer, and Transportation of Radioactive Materials 26 Security of Radioactive Material 26
Storage of Radioactive Material: RAM Sources, Labeled Materials and Waste 26
On-Campus Transfers of RAM 26
Off-Campus RAM Transfers 27
Transportation of Radioactive Material 27
Transportation of RAM on Public Roadways 27
Package Preparation 28
Other important considerations 28
Transportation of RAM or Devices 28
Temporary Job Sites and Remote Locations 28
Reciprocal Licensing 29
I. Radioactive Waste 30 Radioactive Waste Handling 30
Summary of solid waste criteria 30
Summary of liquid waste criteria 30
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Other important considerations 31
Disposal of Equipment with Embedded Sources 31
Radioactive Waste Minimization 32
J. Personnel Exposure 33 Occupational Dose Limits 33
External Dose 33
Internal Dose 33
Sum Of External and Internal Doses 33
Regulatory Dose Limits to Declared Pregnant Workers 34
Occupational Dose Limits for Minors 35
Regulatory Limits for Dose to Individual Members of the Public 35
K. Personnel Monitoring 36 Personnel Dosimeters 36
Whole Body 36
Extremity/Ring 36
Bioassays 37
ALARA and Personnel Exposure Records/Reports 37
L. Laboratory Safety 38 Facility Requirements 38
Procedures, Practices, and Rules for the Safe Use of Radioactive Materials 39
Approved Locations and Equipment 40
Contamination Surveys by Authorized Personnel 40
Annual Reviews 41
Radioactive Material Audits 41
Radioactive Material Surveys 41
M. Emergency & Decontamination Procedures 42 Minor Spills and Contaminations 42
Major Spills and Contaminations 42
Restricting Access to Areas Due to RAM Contamination 43
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Accidents Involving Radioactive Material 43
Decontamination Procedures 44
Clean-up of Radioactive Contamination and Legacy Materials or Devices 45
N. Other Uses of Radioactive Materials 46 Radioiodination 46
Animal and Biological Specimen Use 46
Environmental Releases 46
Appendix I - Guidelines for the Safe Use of Radionuclides 47 Appendix II - Dictionary and Glossary 61 Non-Discrimination Statement 69
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Table of Acronoyms
ALARA As Low As Reasonably Achievable CDE Committed Dose Equivalent CEDE Committed Effective Dose Equivalent DDE Deep-Dose Equivalent DOT U.S. Department of Transportation EH&S Environmental Health and Safety ISU Iowa State University IDPH Iowa Department of Public Health IAC Iowa Administrative Code ORR Office for Responsible Research PPE personal and protective equipment PI Principal Investigators RAM radioactive materials RPD radiation producing devices RSC Radiation Safety Committee RSO Radiation Safety Officer SDE Shallow-Dose Equivalent TEDE Total Effective Dose Equivalent TODE Total Organ Dose Equivalent VPR Vice President for Research
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A. Introduction
Radioactive materials and radiation producing devices have long been used as important tools in research and teaching. Concern over health risks associated with radiation exposure has led to occupational exposure limits and strict regulatory controls governing the possession and use of all sources of ionizing radiation.
Current radiation exposure limits are based upon the conservative assumption that there is no completely safe level of exposure. This assumption has led to the general philosophy and regulatory requirement of not only keeping exposures below recommended levels or regulatory limits, but of also maintaining all exposures ALARA. This is a fundamental tenet of current radiation safety practice.
In order to ensure that all users of ionizing radiation at ISU are in compliance with existing regulatory requirements, and that radiation exposures are maintained ALARA, EH&S has implemented the policies and procedures contained in this Radioactive Materials Safety Manual.
This manual is intended to provide sufficient information to ensure that radiation safety practices at ISU are of the highest quality. It is the responsibility of each person working with RAM to become familiar with the contents of this manual and to observe those procedures and requirements contained herein that are applicable to their work.
This manual is intended to supplement the requirements found in the ISU Laboratory Safety Manual.
For individuals seeking initial authorization approval to use RAM at ISU, a detailed list of the necessary steps for obtaining approval and initiating the use of RAM has been prepared and can be found on the EH&S website.
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B. Regulatory Requirements
The possession and use of RAM and RPDs in the United States are governed by strict regulatory controls. Regulations controlling the use of radiation in Iowa are found in Chapter 136C of the Iowa Administrative Code and are administered by the Bureau of Radiological Health of the IDPH.
ISU holds a broadscope radioactive materials license issued by IDPH. This license grants ISU the authority and responsibility for setting the specific requirements for radioactive material use within its facilities.
All use of RAM under the authorization of the broad scope license is governed by RSC, and is subject to inspections and audits by the IDPH and EH&S for rules compliance and safety performance.
ISU holds separate licenses for Generally Licensed Materials and RPDs. The RSC has oversight of these items. Sealed source users must comply with the requirements in the Sealed Source Safety Manual and RPD users must comply with requirements in X-Ray Safety Manual, respectively. University Policy ISU has established its commitment to the safe use of RAM and RPDs through policies that minimize the hazards of radiation and maintaining radiation exposures ALARA. These policies can be viewed on the ISU Policy Library web page.
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C. Administrative Controls
Environmental Health and Safety EH&S oversees the radiation safety program for ISU. Functions of the radiation safety program include: • accountability for RAM and RPD use on campus • radiation safety training • laboratory inspections • laser safety • waste handling • personnel dosimetry • public exposure
EH&S also has the responsibility for administering all university health and safety programs including: biological, chemical, emergency management, environmental, fire, laboratory, and occupational safety. Radiation Safety Committee In accordance with the specific requirements of the university’s broad scope license for radioactive material use, ISU has established a RSC. The committee consists of university faculty trained in a safe use of radioactive material and includes a member representing university administration, and the RSO. Members are appointed by the Vice President for Research for terms of three years. The principal function of the committee is to oversee the safe use of RAM and RPDs on campus. The RSC reviews all requests for use of RAM and RPDs, grants authorization, and performs audits of the radiation safety program. Functions of the RSC are outlined in the RSC Charter. Radiation Safety Officer The RSO is designated as the radiation safety expert and responsible person who oversees the daily administration and operation of the university’s radiation safety program. The RSO is a permanent member of the RSC and is assisted by EH&S radiation safety staff and student technicians to carry out the daily functions of the ISU radiation safety program.
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University Compliance Committees Iowa State University’s compliance program includes conflict of interest, research integrity, export control, and research compliance review committees. The purpose of the compliance review committees is to review and approve all relevant proposals to ensure that they are in compliance with university, local, state, federal, and funding agency regulations for research. The four review committees administratively reside within the Office for Responsible Research (ORR) and include:
Animals - Institutional Animal Care and Use Committee (IACUC) All activities involving the use of live vertebrate animals must be approved by the IACUC prior to the use of the animals in research or teaching activities. Research activities include field studies, clinical trials, the use of blood donor animals, and breeding colonies. Teaching activities include scheduled courses and continuing education offerings.
Biohazards - Institutional Biosafety Committee (IBC) The IBC must approve any teaching or research project that involves: the use of recombinant or synthetic nucleic acid molecules including transgenic animals or plants; the use of human, animal, or plant pathogens (e.g., bacteria, viruses, prions, parasites); the use of biological toxins; materials received under the USDA APHIS permit the administration of experimental biological products to animals; or field releases of plant pests or genetically modified organisms (GMO).
Humans - Institutional Review Board (IRB) The IRB reviews any research involving human participants, including proposals to gather data from participants for theses, dissertations, and other student projects.
Radiation - Radiation Safety Committee (RSC) All research using radiation must be approved by the RSC. IRB, IACUC and IBC applications using radiation must be reviewed and approved by the RSC, as these committees do not have the authority to approve radiation use.
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D. Process Planning
All research and teaching uses of radiation requires the approval of the RSC. Each new project, changes to existing approvals, and the addition of new research will be reviewed and approved by the RSC. A PI requesting approval to provide services to other laboratories or to use material in an academic course must request approval from the RSC to operate as a research center. Authorization Process The individual responsible for the proposed project, referred to as the PI, begins the authorization process by submitting a completed radioactive materials use application to EH&S. Other application Note: All new applications must forms are available from the radiation safety section of the EH&S be reviewed and approved by the RSC. website. The application must include detailed information in three general categories: information on personnel, facility information and a project description.
Personnel Information It is critical that persons working with radiation have the proper experience and knowledge to safely use radiation and maintain radiation exposures ALARA. The RSC and RSO evaluate all requests from the following information:
Principal Investigator (PI): The person who is responsible for radiation use within their assigned laboratories. This person will establish and lead radiation safety within their laboratories. As the radiation safety lead, the PI is required to maintain their safety training on an annual basis.
Alternate PI: A person authorized to act on behalf of the PI in their absence. The Alternate PI shall maintain their safety training on an annual basis.
Laboratory Supervisor: The person most familiar with daily laboratory functions and radiation use. This person is authorized to make administrative changes to the radiation authorization. The laboratory supervisor shall maintain their safety training on an annual basis.
Authorized Personnel: The people who will work with radiation under the supervision of the PI. The PI must be listed as authorized personnel. Annual radiation safety training is required for all authorized personnel.
Education and Laboratory Experience: Title and credit hours of any course taken in nuclear science, radiation safety or radionuclide use; an indication of whether Iowa State’s radiation
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safety training program has been completed (including the completion date), duration of experience, type, and quantity of radionuclides used, the specific experimental procedures employed, procedures followed for laboratory safety and waste handling. Attach additional sheets to the application if needed.
Facility Description A facility must meet certain requirements in order to be used for work with radiation materials or devices. Determination of facility suitability includes:
Locations of use: Building, floor, room number, department
Room Diagram for each location: Locations of hoods, sinks, benches, exterior/interior walls, windows, doors, intended use, and storage areas
Construction materials: Floors, bench tops, hoods, and sinks
Ventilation: Air exchange rate for the laboratory and the number and type of hoods or glove boxes
Radiation safety equipment: Shielding, waste containers, trays, absorbent paper, spill kit, type of radiation detectors, and radiation counting equipment
Occupancy of facility and adjacent areas: Use of facility by individuals not approved for radionuclide work and use of areas adjacent to the facility
Project Description The project description should include: • standard operating procedures • diagrams • types of equipment used • safety procedures • radionuclides and radioactivity • radiation detection methods • hazardous materials • duration of project • any other information describing the procedure
A journal article, kit instructions, or similar written techniques can be used to satisfy some of these descriptions.
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Research Centers Research centers are laboratories that provide research services to multiple customers, both on and off campus, offer equipment for use by other laboratories, or that serve as an academic laboratory. These centers are required to: • Provide EH&S with written documentation detailing how training records will be maintained (who is in charge, location of records, etc.). • Maintain records of radiation training for all users. • Maintain records of laboratory specific training (i.e. how to properly and safely use the equipment). • Maintain a usage logs. • Ensure that only people with current radiation safety training are allowed to use the equipment. • Allow EH&S to review training records, usage logs, etc during audits. • Contact EH&S prior to making major changes to, or adding new research protocols. • Be aware of other approvals that may be needed (IACUC, IRB, IBC, etc.).
EH&S will audit research centers at least annually. The RSC may require a laboratory to operate as a center based on information provided by the PI. Prior authorization of a procedure does not grant approval for the PI to provide services to other laboratories or operate as a research centers. Review and Approval of Application The completed application must be submitted to EH&S, where it will receive an initial review by the RSO. The RSO may require additional information from the applicant to assess the safety of the procedure. EH&S will also review procedures for additional hazards involving chemical and biological materials, physical hazards, and the use of human and animal subjects. Approval for procedures involving additional hazards may be delayed until safety and regulatory measures are addressed.
Once the application appears to be adequate, the RSO forwards it to the RSC chair for approval. If the application is approved, the PI will receive a copy of the official authorization form listing any special conditions that may apply. The RSC reserves the authority for line item approvals on all applications. Should any portion of the application be denied, the PI will be provided with an explanation for this decision.. The notification will include a description of possible modifications to the project necessary to obtain approval.
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Summary of the Radiation Authorization Application, Review and Approval Process 1. PI completes application. 2. PI submits completed application and supporting documents to EH&S. 3. EH&S reviews application. 4. EH&S submits application with recommendations to RSC. 5. RSC reviews application. 6. RSC notifies EH&S of their decision. 7. EH&S notifies PI and arranges details to set up the laboratory. Radiation Authorization Amendments Modifications to a PIs original authorization may be requested through EH&S in either written or electronic form. Minor changes, such as changes in personnel, additional projects, increased possession limits, or changes in location are reviewed and approved by the RSO. Note: All new protocols must Extensive changes to the authorization such as: adding additional be approved by the RSC. radionuclides or devices, or adding new radiation procedures will be subject to the same review and approval process as the original application.
Adding Authorized Personnel Authorized Personnel are added through the training process. If authorized personnel join another radiation laboratory the change must be submitted to EH&S. You must list a currently approved PI who has approved your addition to their Radioactive Materials Use Authorization.
1. Complete the Radioactive Material Worker Application.
2. Submit the Worker Application to: EH&S, 2408 Wanda Daley Drive, Ames, Iowa 50011-3602 or by e-mail.
3. EH&S will add personnel to the PI’s authorization and send an updated copy to the PI and laboratory supervisor.
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Approval in Concept Approval in Concept may be issued to PIs by the RSC and ORR for Note: A new user may request funded projects where the funding agency has approved an initial an Approval in Concept when period for development of the final protocol and related study materials. applying for a grant. No research with radiation may be conducted under an Approval in Concept. Submission of a RAM or RPDs authorization application will be required to obtain an authorization prior to conducting research. Authorization Termination and Laboratory Closure When a PI no longer uses RAM in their research: they must submit a written request to EH&S for laboratory decommissioning. EH&S will schedule a time to collect materials, complete close out surveys and remove postings from the laboratory.
Authorizations and laboratories may be decommissioned for non- compliance of policies, rules, and regulations under the provisions of the RSC Charter. An authorization may be decommissioned for actions such as the deliberate misuse of materials or devices, or the PI failing to complete annual training requirements.
Authorizations and laboratories with no active radiation projects will be subject to closure. Seeking future funding does not mean an active project. PIs storing material for later use will be subject to all requirements of the rules, including annual training.
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E. Training Requirements
Radiation specific training provides PIs and authorized personnel with knowledge of basic radiation safety theory, techniques, and ISU procedures. Radiation safety training is an ongoing process and consists of an initial training course and annual retraining. Multiple training courses are required for multiple types of authorizations since policies, rules, and procedures differ for RAM. Additionally, laboratory safety training, as specified in the Laboratory Safety Manual shall be completed to meet Occupational Health and Safety Administration (OSHA) requirements.
Personnel Initial Training Retraining Course(s) Course and Frequency
Radioactive Radiation Safety Radiation Materials for Material Users - Safety for (RAM) Users Part 1 (online) Material Users Radiation Safety Refresher Note: RAM refresher training is (online) required annually!! for Material Users - Part 2 (online) Jan.- Feb. is Radiation Safety retraining period for Material Users - Part 3 (online) Radiation Safety for Material Users - Part 4 (Laboratory)
Laboratory Radiation Radiation Personnel Awareness Training Awareness in a RAM (online) Training laboratory 3 yrs.
Service Radiation Radiation Personnel – Awareness Training Awareness Custodial and (online) Training Maintenance 3 yrs. staff
Note: See Sealed Source and/or X-Ray Manual for appropriate training courses.
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Radioactive Material Users RAM training is required for all authorized personnel using radioactive materials, especially any type of open form radionuclides. This training will provide a basic understanding of ionizing radiation and its potential hazards, as well as knowledge of the particular rules, regulations, and university processes governing RAM use. Online training modules are available through Learn@ISU with a performance based laboratory module held at the EH&S Learning Center. All modules must be completed to satisfy the initial radiation safety training requirement.
Annual retraining is online through Learn@ISU. PIs and authorized personnel will be reminded by EH&S of dates to complete the training (January - February). Those who do not complete the annual retraining within the established time frame will be removed as authorized personnel and will need to repeat the initial four part radiation safety training for materials users. Awareness Training for Laboratory Personnel Anyone working in laboratories that are not approved radiation personnel, but have access to locations where radiation is used, are required to complete radiation awareness training. Topics include a basic introduction to radiation; recognizing the meaning of radiation symbols and warning signs; and understanding safety rules, security rules and emergency procedures when working in a containing RAM. This training is required when personnel join a laboratory and then every three years.
Service Personnel Working in a Radiation Laboratory This online awareness course provides non-laboratory support staff, such as custodians and maintenance workers, with an overview of basic radiation safety. Participants will learn what is required of them when providing services for laboratories in which radioactive materials are used. Topics include a basic introduction to radiation; recognizing the meaning of radiation symbols and warning signs; and understanding safety rules and emergency procedures when entering a laboratory containing radioactive materials. This training is required prior to providing services to a radiation laboratory and then every three years. Radiation awareness training is an online course available through Learn@ISU.
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Minors Visiting or Completing Work in a Radiation Laboratory Iowa State University policies outline the requirements of laboratory access for people less than 18 years of age. The policies exist to reduce risks to minors who visit or work in laboratories or shops. Consult the ISU policy library for Children in the Workplace. Authorization of minors to use radiation will be at the discretion of the RSC based on input from the PI. At a minimum, minors working in laboratories approved for radiation use are required to complete radiation awareness training. Laboratory Specific Training Documented lab-specific training is required annually. Recommended topics include: • laboratory SOPs • manufacturer’s operating instructions • potential hazards • transfer and disposal requirements
See the ISU Laboratory Safety Manual for more information.
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F. Responsibilities
At ISU trained radiation users share the responsibility for ensuring the safe use of radiation. Failure to comply with this responsibility may result in termination of a user’s authorization to use radiation. These responsibilities are summarized below. Responsibilities of the Principal Investigator The individual authorized by the RSC as the PI on a project involving the use of radiation is responsible for all activities conducted under the scope of that authorization. The PI has the responsibility for ensuring that: • All individuals working with radiation have completed all university and laboratory safety training requirements including the required annual refresher training. • All individuals working with radiation have been formally authorized by the RSC. • All rules, regulations and procedures for the safe use of radiation are followed. • An accurate record of the types, quantities and locations of radioactive materials and devices is maintained. • EH&S is notified of any changes in the storage or use of radiation materials (RAM) and devices prior to implementing the changes. • All uses of radiation are constantly evaluated to further reduce exposures to individuals ALARA. • All procedures for using RAM are current and accurate. • All radioactive sources or source material are secure from unauthorized access or removal. • EH&S is notified of all unusual events or conditions that occur in the laboratory, including spills, releases, missing inventory, etc. • EH&S is informed when authorized personnel leave the laboratory. • EH&S is informed when ending the use of RAM or devices • EH&S is notified when leaving the university.
The entire laboratory authorization for radiation use may be revoked for non-compliance of policies, rules, and regulations following the guidelines set forth in the RSC Charter.
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Responsibilities of the Authorized Personnel Personnel authorized to use RAM are responsible for its safe use. Each user must: • Minimize their personal exposure to ALARA. • Minimize public exposure to ALARA. • Wear assigned dosimetry as specified in this manual. • Understand and comply with all sections of this manual that apply to their work. • Identify the location of all radiation sources in the work area and the extent of their potential risks, and use the appropriate procedures to minimize the risks. • Monitor the work area frequently for contamination or exposure and document the results. • Clean minor contaminations immediately; Do not leave contamination for another person to clean up. • Dispose of radioactive waste properly • Maintain postings, labels, and markings for all sources, containers, and work areas. • Maintain usage logs, records, and inventories. • Prevent unauthorized persons from access to radioactive material and devices. • Protect service personnel, by restricting all maintenance or repairs • Notify EH&S of all unusual events or conditions that occur in the laboratory, including spills, releases, missing inventory, etc. • Complete all required training within the set time period specified by the RSC. • Report spills, contaminations, or personal contamination to EH&S.
The individual’s authorization to use radiation may be revoked for non- compliance of policies, rules and regulations under the provisions of the RSC Charter.
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G. Obtaining Radioactive Material
In order to ensure proper management of the types and amounts of RAM and devices entering the ISU campus, all purchases of these items must be approved and processed by EH&S. ISU is required to provide proof of licensing to the vendor prior to transfer or shipment. Ordering Radioactive Material A copy of ISU’s current broad scope license must be on file with all companies or licensees before ordering. Contact EH&S at (515) 294- 5359 to request a copy of this license be sent to the vendor. It is the vendor’s responsibility to obtain the license prior to shipment.
Radioactive Material Ordering Procedures: • Authorized personnel initiate the procurement process by Note: All RAM must be contacting EH&S to obtain a log number. Information required delivered to EH&S. for issuing a log number: ¤¤ Name of PI ¤¤ Name of end user ¤¤ Phone number to contact when delivered ¤¤ Nuclide supplier/vendor ¤¤ Nuclide(s) being ordered ¤¤ Total nuclide cctivity, in mCi ¤¤ Chemical form • EH&S checks the type and amount of the radionuclide to be ordered against the authorized PI’s approved amount and current inventory. • If the request does not increase the PI’s inventory beyond authorized activity limits, EH&S will assign the order a log number. • If the user is utilizing Perkin Elmer, the order may be placed in the cyBUY system by accessing the Perkin Elmer catalog. The log number should be entered in the “attention” line of the cyBUY release. All Perkin Elmer orders will ship to the EH&S address shown at the end of this section. • If the user is using a different vendor for ordering RAM, they must complete a requisition to Procurement Services requesting that a purchase order (P.O.) be issued to the vendor. The requisition should reference the log number in the purchasing notes. Procurement Services also has contracts in place for radioactive materials. Contact the Procurement Services to get information on the radionuclide contracts and how to place orders on those contracts. Procurement Services will not issue a P.O. number if the order has not been assigned
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an EH&S log number. • The vendor must also be instructed to reference the log number on the packing slip accompanying the order. • A log number is required even if a purchase order is not used to procure the material (examples: evaluation materials, materials transfer from non-vendors, or materials forwarded to a new PI). • In accordance with RAM license requirements, the vendor must be instructed to address the shipment to EH&S. Do not address RAM packages for delivery directly to your laboratory. Iowa State University Environmental Health and Safety 1122 Environmental Health & Safety Services Bldg 2408 Wanda Daley Drive Ames, Iowa 50011-3602 Log Number: xxxx-xxxx RAM, devices with embedded sources, sealed sources, or generally licensed materials must be purchased through an university issued purchase order number or established vendor contract issued by Procurement Services. Receipt and Delivery of Radioactive Material Upon receipt of a radionuclide shipment, EH&S staff will check the RAM package to ensure that radiation exposure levels and contamination levels are within regulatory limits.
If a RAM package is mistakenly delivered directly to your laboratory, inform EH&S immediately. EH&S staff will then enter the radionuclide data into the PI’s RAM inventory and deliver the shipment to the user’s laboratory. Late packages received by EH&S will be processed when received, but may not be delivered to the PI until the following day.
An approved RAM user must sign for the RAM package upon delivery to the laboratory. At least one radionuclide usage and inventory form will accompany each package stating the activity and radionuclide present. The lower portion of the inventory sheet (the source/vial consignment sheet) must be returned to EH&S with the RAM when work with the material is completed or the material is no longer useful. EH&S will then remove the material from the PI’s inventory and ensure proper disposal.
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Receipt of Free/Gifted/Evaluation Materials and Note: A log number is still needed for Free/Gifted Devices materials. Free, gifted, or evaluation materials or devices must follow the same procedures outlined above. Additionally, RAM, devices, and other radiation sources transferred to ISU by new faculty and staff require EH&S notification and approval of the RSC.
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H. Security, Storage, Transfer, and Transportation of Radioactive Materials
Any transfer of RAM or devices or equipment containing RAM or embedded sourced must be approved by EH&S before the transfer takes place. Security of Radioactive Material Security of RAM must be practiced at all times. RAM (i.e. source material, sealed sources, devices containing sources, labeled materials, and waste) must be in constant attendance by the trained user, or otherwise locked or secured to prevent unauthorized removal or tampering.
Storage of Radioactive Material: RAM Sources, Labeled Materials and Waste RAM shall be secured from unauthorized access in cabinets, refrigerators, freezers or waste areas, unless attended by authorized personnel. These storage containers must have locks with keys or combinations available only to authorized individuals. RAM shall be stored in sealed containers to prevent accidental spillage, breakage, contamination and to prevent release. If the radionuclide requires shielding, containers will be shielded to maintain ALARA and prevent excessive or unnecessary exposure.
Radioactive material stored in a freezer, should be thawed, opened, and handled in a fume hood or biological safety cabinet. Aerosols from stored RAM may cause contamination of adjacent areas and RAM intake by personnel if not handled properly after storage. All RAM must be marked radioactive and indicate the radionuclide.
Any material or collection of items, such as a bag of trash or pieces of equipment, that are contaminated with RAM are considered a radioactive material and must be labeled or marked as RAM with the radionuclide indicated. On-Campus Transfers of RAM Transfer of RAM or devices between laboratories at the university must be approved by EH&S and is dependent upon the PIs respective authorizations. EH&S will update inventories for both laboratories and issue new inventory forms after the transfer. The following information must be submitted to EH&S: • dates when the material will be moved • sending and receiving locations
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• radionuclide(s) being moved • chemical form of the radionuclide • total activity (dpm,µCi, mCi or Bq) • number of containers • telephone numbers or responsible person(s) • mode of transport • any special conditions (biological or chemical hazards or presence of dry ice) Off-Campus RAM Transfers Off campus transfers of RAM will necessitate shipment of the material using a commercial carrier or occur over public roadways and DOT regulations will apply. Transportation of RAM using an ISU or personal vehicle is not authorized without prior consent by EH&S. The PI’s laboratory is responsible for all costs associated with RAM shipments including packaging and carrier costs. Contact EH&S to initiate the process, the following information is required: • the name and phone number of the receiver’s RSO • the receiver’s full address a copy of the receiver’s RAM license • dates when the material will be moved • sending and receiving locations • radionuclide(s) being moved • chemical form of the radionuclide • total activity (dpm,μCi, mCi or Bq) • number of containers • telephone numbers or responsible person(s) • mode of transport • any special conditions (biological or chemical hazards or presence of dry ice)
Shipments of RAM must be planned at least two weeks in advance to complete approvals, licensing, packaging, and shipping papers. Transportation of Radioactive Material Transportation of RAM on Public Roadways Transportation of radioactive material must be in accordance with ISU, IDPH, and DOT rules. EH&S must be notified before any shipments take place.
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Package Preparation All packaging used to transport RAM must meet the performance criteria for the material being shipped. To assist in this process EH&S will: • Offer advice in selecting proper performance packaging. • Help determine the best mode of shipment.
After the package is obtained, laboratories must submit the RAM in the unsealed package to EH&S with a parcel post mail card. EH&S will verify packing and affix proper markings, labels, shipping papers, and arrange for pickup by the courier.
Other important considerations Liquid RAM requires either double containment or the container be packaged with an over-pack and box with enough absorbent material to contain twice the actual volume of liquid.
Any other questions concerning transportation and packaging should be directed to EH&S. Transportation of RAM or Devices Iowa State University personnel may be required to transport RAM to non-ISU property for diagnostic or research purposes. IDPH and DOT rules for shipment and carriage must be followed. EH&S must approve all transportation of RAM to off-site locations. The approval will include the shipper, carriage, and security measures. Only ISU vehicles may be used to transport RAM or devices containing RAM, unless specific approval is given by EH&S. Temporary Job Sites and Remote Locations Occasionally, RAM, instruments, and devices containing radioactive sources will be used at temporary job sites or remote laboratories. Job sites located outside of Iowa require reciprocal licensing to be in place and three days advance notice before travel may begin. All transportation, posting, security and notification requirements under the local rules apply to remote locations. Remote job sites are subject to audits and inspections by EH&S and the governing regulatory agency. The use of RAM at all temporary job sites and remote locations must have the prior approval of the RSO.
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Reciprocal Licensing Note: Reciprocity may take four to six weeks for approval. The use of RAM or devices outside of Iowa requires licensing by the regulatory agency with jurisdiction at the work location. Typically, the governing agency will grant a one year reciprocal license allowing ISU to operate within their jurisdiction for 180 working days. All costs for reciprocal licensing are the responsibility of the PI or department conducting the work. Reciprocal licensing must be planned well in advance. Allow at least four weeks to complete approvals and licensing procedures.
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I. Radioactive Waste
Radioactive Waste Handling EH&S is responsible for the collection, processing, and disposal of all radioactive waste generated at ISU. For radioactive waste collection, submit an online waste removal request form. A radioactive waste tag must be affixed to the waste container prior to pickup.
In order to facilitate waste management, RAM users are required to follow a number of specific procedures regarding radioactive waste generated in their laboratories. These procedures guide the user in segregating their waste by both physical and chemical forms, and according to the radionuclide’s half-life.
Segregation by half-life sorts the radionuclides into three categories: • Very short-lived – half-lives less than 15 days • Short-lived – half-lives between 15 and 90 days • Long-lived – half-lives greater than 90 days
Diagrams of the waste segregation schemes can be found in the appendixes and on EH&S website.
It is possible that multiple waste containers will be required for proper segregation. Waste bins for solids must be lined with a plastic bag. Other criteria are listed below.
Summary of solid waste criteria • Separate and label according to whether it is combustible (plastics, paper, etc.) or noncombustible (glass, metal, etc.). • Sharp items such as needles, razor blades, and broken glass must be placed in rigid, leak proof, puncture-resistant, plastic containers. Items that are also contaminated with biohazardous material must be packaged according to the criteria above and be denatured before EH&S collection. • Lead (Pb) source containers and source vials must be bagged separately from other solid waste. • RAM waste consignment sheets must be submitted with the source vials, but must not be placed inside the waste bag.
Summary of liquid waste criteria • Liquid radioactive waste must be separated and labeled according to whether it is aqueous (miscible in water) or bears solvents. • The PI must inform the RSO if solvent bearing wastes containing radionuclides will be generated.
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• Compatible liquid waste can be co-mingled, otherwise multiple waste containers are required. • Appropriate secondary containment is required. • Flammable solvent bearing waste, such as those containing toluene or xylene, must be placed in containers specifically approved for flammable liquids. Original solvent containers are acceptable.
Other important considerations Radioactive animal carcasses, viscera and blood must be sealed in a plastic bag or plastic container, labeled, and frozen prior to removal by EH&S. Laboratory personnel must also notify EH&S in advance of any special problems regarding the waste (animal size, fluid leakage, putrefaction, biohazard, etc.) and be prepared to provide assistance at the time of removal.
Unless approved by EH&S, all scintillation vials must be emptied into a liquid waste container and recapped prior to disposal. The only exceptions are plastic vials with biodegradable cocktails containing 14C or 3H.
All radioactive waste awaiting collection by EH&S must be properly packaged and labeled, and placed in a designated waste accumulation area. Solid and liquid waste containers, plastic bags, and radioactive waste labels are supplied by EH&S.
EH&S will provide guidance for unwanted RAM that do not fit established disposal processes. Items may include equipment with embedded RAM sources such as gas chromatographs and liquid scintillation counters, or contaminated equipment, abandoned legacy materials, and materials with multiple hazards. Disposal of Equipment with Embedded Sources Note: Storing items for the Disposal of equipment containing embedded sources will be purpose of avoiding disposal fees is not allowed. completed through ISU Surplus and the equipment manufacturer, under guidance of EH&S. Disposal will be completed following the laboratory equipment disposal method through ISU Surplus website.
If the equipment manufacturer cannot be located or refuses transfer then EH&S will assist the PI or department with an alternate disposal method. The PI and/or department may be responsible for all costs Note: The PI may be responsible for disposal costs. associated with current and legacy equipment disposal. Equipment storage is not permitted to avoid disposal expense. Non-operational equipment containing embedded sources should be identified, repaired, transferred or disposed within a reasonable amount of time. Common equipment containing embedded sources includes gas chromatographs, liquid scintillation counters, emergency exit signs and static elimination devices.
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Radioactive Waste Minimization Each user is encouraged to develop methods and procedures that reduce the amount of radioactive waste generated. Waste minimization techniques include: • Reviewing procedures to ensure that unnecessary waste is not being generated. • Ordering minimal amounts of RAM. • Avoiding accumulation of RAM. • Monitoring waste items for detectable contamination prior to disposal as radioactive waste. If the item, such as gloves, is not contaminated, dispose of the item as non-radioactive waste. • Restricting work to easily decontaminated surfaces (stainless steel trays or absorbent paper) to minimize the amount of waste generated from a small spill. • Using plastic LSC vials instead of glass, whenever practical. • Substituting non-RAM methods, such as fluorescence. • When possible, use short-lived radionuclides instead of longer lived radionuclides.
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J. Personnel Exposure
Occupational Dose Limits Current limits for occupational radiation exposure have been established at levels to: • prevent deterministic/acute radiation effects (erythema, epilation), and • minimize late/stochastic effects such as cancer or genetic damage to very low levels.
These limits set by IDPH are based on the combination of external and internal exposures. To better understand the annual occupational exposure limits set by these regulatory agencies, the definitions of these limits are discussed below:
External Dose • Shallow-Dose Equivalent (SDE) is the dose to the skin from an external source of ionizing radiation. • Eye (Lens) Dose Equivalent (LDE) is the dose equivalent to the lens of the eye from an external source of ionizing radiation. • Deep-Dose Equivalent (DDE) is the whole-body dose from an external source of ionizing radiation.
Internal Dose • Committed Dose Equivalent (CDE) is the dose equivalent to organs or tissue that will be received from an uptake of radioactive material. • Committed Effective Dose Equivalent (CEDE) is the dose equivalent for the whole body from an uptake of radioactive material.
Sum Of External and Internal Doses Total Organ Dose Equivalent (TODE) is the dose equivalent to the maximally exposed organ or tissue from external and internal sources of ionizing radiation.
TODE = DDE + CDE
Total Effective Dose Equivalent (TEDE) is the dose equivalent to the whole body from the combination of external and internal sources of ionizing radiation.
TEDE = DDE + CEDE
Table 1 provides a summary of the current annual occupational dose limits for external and internal exposures.
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TABLE 1. Annual Occupational Dose Limits for Adult Workers Limit rem* Sievert (sv) Shallow Dose Equivalent, Whole-body 50 0.5 Shallow Dose Equivalent, Max. Extremity 50 0.5 Eye Dose Equivalent to the Lens of the 15 0.15 Eye Total Organ Dose Equivalent 50 0.5 Total Effective Dose Equivalent (TEDE) 5 0.05 *rem = the special unit of dose equivalent. Sievert is the S.I. dose equivalent unit. (1 rem = 0.01 sievert).
Internal exposure limits are addressed through the establishment of “annual limits on intake”. The annual limits on intake is the activity of a radionuclide taken into the human body over one year that will deliver 5 rems (0.05 Sv) of committed effective dose equivalent to the body or organ committed does equivalent of 50 rems to any individual organ.
Regulatory Dose Limits to Declared Pregnant Workers Federal and state regulatory agencies have adopted the National Council on Radiation Protection recommendations on radiation dose limits during pregnancy. However, the regulations only apply Note: The first trimester is the when a worker voluntarily declares their pregnancy. If a declaration most critical. Declare early! of pregnancy is made, the worker grants consent to their employer to limit their dose to a TEDE of 500 mrem (5 mSv) throughout the entire pregnancy. If no declaration is made to the employer, their occupational dose limits remain the same.
A declaration of pregnancy must be made to the RSO in writing, and can be made at any time during the pregnancy. Upon receiving the Declaration of Pregnancy form, EH&S will schedule a counseling session with the worker to review their dose history, current work, dose limits and explore methods for minimizing radiation exposure. The declaration of pregnancy can be revoked by the worker at any time and will end upon parturition. The records of dose for the embryo/ fetus will be permanently maintained by EH&S in the declared pregnant worker’s dosimetry files.
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Occupational Dose Limits for Minors A minor is anyone under 18 years of age. The annual occupational dose limits for minors are ten percent of the annual dose limits specified for adult workers. This equals a TEDE of 500 mrem(5 mSv)/year).
Regulatory Limits for Dose to Individual Members of the Public The limit for radiation doses to non-radiation workers and members of the public is two percent of the annual occupational dose limits. For the whole-body dose, this is a TEDE of 100 mrem (1 mSv) per year.
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K. Personnel Monitoring
A number of devices and methods exist for assessing an individual’s exposure to radiation. Whether one or more of these personnel monitoring methods is employed for a given situation will depend upon a number of factors, including the type and quantity of RAM used and the amount of time spent working with the material, or the use of devices. Personnel Dosimeters State and federal laws require that any individual likely to receive a dose in excess of 10% of the limits be monitored. There are numerous types of materials or devices that are used to assess an individual’s cumulative external radiation dose. These are collectively termed “dosimeters”. Dosimeters are issued to monitor both whole-body and extremity exposures. Periodically, dosimeters are exchanged by EH&S and forwarded to the vendor’s laboratory for analysis.
Whole Body Whole-body dosimeters are issued for work with or near sources emitting penetrating radiation (energetic beta particles, x-rays, gamma rays, or neutrons). Whole body dosimeters monitor external radiation exposures.
Extremity/Ring Ring dosimeters are worn by individuals handling relatively large quantities of energetic beta or gamma emitting radionuclides, such as 32P or 125I. Ring dosimeters monitor extremity exposures or exposures to limbs beyond the elbow and knee.
A whole body badge will be worn on the front of the torso between the shoulders and the waist near the portion of the body that is most likely to receive the maximum radiation exposure and under any protective clothing. If a protective apron is worn, the dosimeter should be near the midline of the body under the apron.
An additional dosimeter will be worn for the purpose it was issued such as eye, upper extremity or fetal monitoring. A dosimeter issued to monitor the eyes will be worn on the collar. A dosimeter issued to monitor an upper extremity exposure will be worn on the sleeve. Ring badges should be worn beneath gloves and turned towards the radiation source. The ring badge is usually worn upside down or facing the palm side of the hand. Further instruction on proper dosimeter use and storage can be found on the EH&S website.
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Bioassays Assessing internal radiation exposures is far more difficult than the determination of external exposure. Procedures for this purpose are collectively termed “bioassays”. For many water-soluble compounds labeled with low energy beta emitters, such as ³H and 14C, urinalysis bioassay is conducted utilizing liquid scintillation counting. For radionuclides of iodine, internal exposure may be assessed by using a NaI scintillation probe to externally measure the amount of ionizing radiation emitted from the thyroid.
In general, urinalyses are performed by EH&S only for unusual situations such as accidents involving potential radionuclide uptake or for certain experimental procedures where ingestion or inhalation of radionuclides is possible. Thyroid bioassays, on the other hand, are conducted whenever individuals perform radio iodinations or may have come into contact with volatile iodine compounds. Personnel who receive an intake of RAM will be referred to Occupational Medicine Office. ALARA and Personnel Exposure Records/Reports At ISU, all authorized personnel will have a radiation dose history record, regardless of their monitoring requirement. All personnel monitoring records are maintained by EH&S.
Personnel monitoring results are reviewed quarterly by EH&S radiation safety staff to assure that radiation doses are kept ALARA.
An annual occupational dose report will be sent to any individual whose dose exceeds 100 mRem. Dose reports will be supplied to any participant at their request. EH&S will only release dose reports when a signed request is submitted by the participant.
An individual will be notified by EH&S whenever current monitoring results exceed established ALARA limits. EH&S will meet with the individual to determine the cause of elevated dose, and will review work practices to identify methods to reduce exposure.
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L. Laboratory Safety
The Laboratory Safety Manual outlines the minimum requirements for safe laboratory operations at ISU. PIs and authorized personnel will be subject to the requirements of the Laboratory Safety Manual.
The potential hazards associated with working with RAM and other sources of ionizing radiation can be minimized through the use of appropriately designed and constructed facilities and by adherence to standard laboratory safety rules and practices. Facility Requirements The majority of research laboratories at ISU can be classified as chemical laboratories. In most cases, these laboratories are adequate for the use of RAM. For certain types and uses of RAM, however, additional facility requirements must be met. The specific requirements, which will likely vary from one situation to another, are determined by EH&S.
General minimum facility requirements for use of RAM: • Floors must have smooth, nonporous, easily cleanable surfaces. Appropriate floor materials include vinyl, tile and sealed concrete. Benches must have nonporous, easily decontaminated surfaces. Surfaces of high-quality plastic laminate or stainless steel are preferable. Sinks should be stainless steel or of seamless molded construction. • Hoods, when required, must be currently tested and certified by EH&S, preferably constructed of stainless steel or molded fiberglass. For additional guidance see the Laboratory Safety Manual. • ISU’s current design manual states that laboratories will be designed with eight air exchanges per area occupied; four air exchanges unoccupied. The actual rate required will vary with the potential for radionuclide release to the air within the particular laboratory. • Shielding must be provided when appropriate (for laboratories using large quantities of gamma or high-energy beta-emitting radionuclides). Specific requirements will be determined by EH&S on a case-by case basis.
In addition to the above requirements, the following guidelines should be considered for facilities used to house animals containing RAM: • Floors should be designed so that they may be cleaned and the wash water either drained to the sanitary sewer or to a container that can be removed for proper disposal. • Holding pens and cages should be designed and positioned in a
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manner which will minimize contamination, allow for the collection of radioactive urine and feces, and facilitate cleaning.
Procedures, Practices, and Rules for the Safe Use of Radioactive Materials In general, both internal and external exposures to ionizing radiation can be maintained ALARA through the adherence to a number of standard procedures, practices and rules. These include: • RAM must be protected from unauthorized removal or access at all times. • Eating or drinking is not permitted in radionuclide laboratories. • Food, drink, tobacco products, gum, medications, or cosmetics are not allowed in areas where radioactive materials are used or stored. • Pipetting by mouth is not permitted in radionuclide laboratories. • Microwave ovens in radionuclide laboratories must not be used for heating food or beverages. • Individuals who have not been approved for radionuclide use must neither work with nor handle RAM. • Security of RAM, sources, samples and waste must be maintained at all times to prevent unauthorized removal or tampering. • A “Caution-Radioactive Material” sign must be conspicuously posted at each entrance of a radionuclide laboratory. • Locations within the laboratory where radionuclides are used or stored (hoods, refrigerators, microwave ovens, etc.) must also be labeled indicating the presence of radioactive material. • A “Radiation Safety” posting including emergency procedures and a State of Iowa “Notice to Employees” must be posted. • Radionuclide work areas must be clearly designated and should, to the extent possible, be isolated from the rest of the laboratory. The work area must be within a hood if the RAM to be used is in a volatile form. Note: Contamination surveys • All work surfaces must be covered with absorbent paper, keep RAM from going home which should be changed regularly to prevent the build-up with you! of contamination. Work involving relatively large volumes or activities of liquid RAM should be performed in a spill tray lined with absorbent paper. • Procedures involving RAM should be well-planned and, whenever possible, practiced in advance using non-RAM. • Protective clothing appropriate for the work conditions must be worn when working with RAM. This includes laboratory coats, gloves, protective footwear, and safety glasses. Open footwear
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cannot be worn in ISU laboratories. • Dosimeters, if issued, must be worn when working with RAM. • All containers of RAM must be marked radioactive with the radionuclide indicated. • All items suspected or known to be contaminated must be marked as radioactive. • All contaminated waste items must be placed in a container specifically designated for radioactive waste. Sharp items, such as needles or razor blades, shall be placed in a cardboard box, glass bottle, or “sharps” container. • A radiation survey must be performed by the radionuclide user at the end of each procedure involving RAM and the results of the survey recorded and maintained. • A record of the types and quantities of radionuclides possessed by each PI at a given time must be maintained. Approved Locations and Equipment RAM use is allowed only in areas posted as a RAM use area. Likewise, equipment used with RAM shall be marked with a radiation marking. Equipment cannot be removed from the designated laboratory until it has been surveyed, decontaminated and deemed free of RAM. Marked equipment can be consigned to waste in lieu of decontamination. Contamination Surveys by Authorized Personnel Contamination surveys must be completed by authorized personnel after each use of RAM or at the end of each day for procedures lasting multiple days. The surveys are conducted using a portable survey instrument, smear samples, or both, depending on the radionuclides used. If measurements are found to exceed two times the background reading, initiate appropriate decontamination procedures.
All items found to be contaminated must be placed either in a radioactive waste container or marked as radioactive with the radionuclide specified, and placed in a designated area. Any surfaces found to be contaminated must be marked radioactive and decontaminated as soon as possible. A follow-up survey is required following the decontamination procedures.
The survey should always include a check of personnel for possible contamination. EH&S must be notified immediately if extensive contamination is found within the laboratory or if any personnel are found to be contaminated. All survey results must be recorded and the survey records maintained in the lab.
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Annual Reviews In order to ensure that safety rules are observed and that RAM has been adequately controlled and used, EH&S staff conducts periodic surveys and audits of radiation laboratories. During these audits general safety surveys will also be completed. The criteria for the general safety surveys can be found on the EH&S website.
Radioactive Material Audits Radionuclide laboratory audits are performed at least annually. During each audit, the PI‘s radionuclide inventory, authorization, RAM processes, training records, and contamination survey records are reviewed and worker performance is evaluated. Any problems encountered by EH&S during the audit are discussed with laboratory staff or the laboratory supervisor and, when necessary, with the PI. Authorized personnel are responsible for correcting any problems identified through EH&S audits. Written corrective action plans may be required by EH&S. EH&S is available to assist the laboratory in correcting problems. RAM inspection criteria is available for laboratory use at the EH&S website or by contacting EH&S radiation safety staff.
Radioactive Material Surveys EH&S completes compliance surveys in active research spaces at least quarterly and support spaces are surveyed at least annually. During each survey, both external radiation levels and surface contamination levels are monitored. Any problems encountered by EH&S during the survey are discussed with laboratory staff or the laboratory supervisor and, when necessary, with the PI. Laboratory personnel are responsible for correcting any problems identified through EH&S surveys. Written corrective action plans may be required to be submitted to the EH&S. EH&S is available to assist the laboratory in correcting problems.
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M. Emergency & Decontamination Procedures
Despite the strict adherence to all laboratory safety rules RAM accidents can occur. For this reason, it is important that RAM users are aware of the proper procedures to follow for various types of accidents. All spills and contaminations must be cleaned up immediately. EH&S Note: EH&S is responsible is available to assist the laboratory in decontamination and spill for restricting access to cleanup efforts. contaminated areas. Minor Spills and Contaminations Incidents involving the release or spillage of less than 100 µCi of a radionuclide in a nonvolatile form can generally be regarded as minor. For small spills and contaminations laboratory personnel are required to clean up the spill following these steps: 1. Immediately notify all other persons in the room. 2. Clear the room of all persons except those needed to clean up the spill. 3. Contain the spill immediately. 4. Liquids - cover with absorbent paper or absorbent chemicals (calcium bentonite). EH&S has prepared standard spill control kits, available from Chemistry Stores. Note: Treat life threatening 5. Solids - dampen thoroughly, taking care not to spread injuries before worrying about contamination. Use water, unless a chemical reaction would contamination! occur. 6. Notify the PI. 7. Notify EH&S (515) 294-5359. 8. After hours, notify Department of Public Safety (515) 294-4428. Major Spills and Contaminations An incident occurring outside of the hood and involving the release of more than 100 µCi of a radionuclide in a nonvolatile form, or the release of any amount of a radionuclide in a volatile form, should be considered major. EH&S will direct the spill response and decontamination for major spills and contaminations. Laboratory personnel are responsible for immediately completing the following steps: 1. If safe to do,evacuate the room shutting doors and windows on the way out. 2. Notify the PI. 3. Notify EH&S (515) 294-5359. 4. After hours, notify Department of Public Safety (515) 294-4428 5. Restrict access to the laboratory by posting a “Keep Out” or similar
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sign on the laboratory door(s). 6. Assemble those persons who were present in the laboratory near the entrance of the laboratory and wait for EH&S assistance. Except for a medical emergency, do not leave the area until you have spoken with EH&S.
Restricting Access to Areas Due to RAM Contamination IDPH must be notified when access to an area is restricted for more than 24 hours due to radioactive contamination. EH&S will complete all notifications to IDPH, when required. If decontamination is completed in less than 24 hours, no notification is required. Note: Notify EH&S of any personnel contaminations! Accidents Involving Radioactive Material For any accident involving personal injury, medical treatment or assistance will always be the first priority. This may involve administering first aid and/or calling 911 for emergency medical assistance. In accidents involving RAM contamination and exposure control are also important, but should never delay or impede medical assistance. If any RAM is involved, EH&S must be notified as soon as possible to evaluate any potential for radiation contamination.
If possible, assist injured or exposed personnel and administer immediate first aid, which may include: • Move injured personnel only if necessary to prevent their exposure to further harm. • For spills affecting small portions of skin, immediately flush with flowing water for at least 15 minutes. If no visible injury exists, wash with warm water and soap, removing any jewelry to facilitate proper decontamination. • For spills on clothes or large areas of skin, quickly initiate showering while removing all contaminated clothing, shoes and jewelry. It may be necessary to cut the clothes off in some instances to prevent contamination of the eyes. • Contaminated clothes should be turned over to EH&S and laundered when possible (at work separately from other clothing or using a contracted laundering service) decontaminated or discarded. Never take contaminated clothing home. • Do not use creams, lotions, or salves, except to neutralize the spilled material (e.g., calcium gluconate gel for hydrofluoric acid exposure and polyethylene glycol [PEG 300] for phenol exposure). • For splashes into the eyes, immediately irrigate the eyes at an eyewash station for at least 15 minutes. Hold the eyelids away from the eyeball, moving eye in all directions to wash thoroughly behind the eyelids.
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• Administer first aid as needed.
In all cases, the exposed or injured person must seek medical attention: Note: The survey instrument used for contamination • Call 911 for medical emergencies. monitoring shall be appropriate • After the injured person is treated and removed from the accident to the radiation being detected. site, the previously described spill procedures should be followed. • Additional information can be found in Exposure Assessment & Medical in the Laboratory Safety Manual. Decontamination Procedures If survey readings are found to exceed two times the background reading, initiate appropriate decontamination procedures. For contamination incidents, the following general steps should be taken: 1. Wear appropriate personal and protective equipment: lab coat, eye protection, gloves, and possibly shoe covers. 2. Mark the perimeter of the contaminated area. 3. Notify EH&S of the contamination so that radiation safety staff can more accurately assess the extent of the contamination and advise and assist in the decontamination effort. 4. Assemble cleaning supplies such as paper towels, detergent solution, plastic bags, gloves, and shoe covers. 5. Proceed with scrubbing the area from the borders to the center, cleaning small areas at a time. 6. Periodically monitor the effectiveness of the decontamination effort with surface wipes and instrument surveys. 7. Decontamination limits are listed in Table 2. 8. Place all contaminated cleaning materials, such as paper towels, rags and gloves, in a plastic bag and label as radioactive waste. 9. Notify EH&S (515) 294-5359 upon completion of the decontamination effort so that a follow-up contamination survey can be made.
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TABLE 2. Limits of Radioactive Contamination TIP: on Surfaces or Items to be Released for Unrestricted Use EH&S maintains control of all carrier free radioiodine. Contamination Type Limit 2 Removable alpha (wipe) 10 dpm/100 cm
2 Removable beta/gamma (wipe) 200 dpm/100 cm Fixed alpha (direct measure) * non-detectable Fixed beta/gamma (direct measure) ** 0.1 mrem/hr at 1 inch
* Non-detectable is a reading less than the average instrument background plus 10%.
** Reading from a survey instrument with the beta shield open and a maximum distance of 1 inch from the surface of the detector tube to the surface being monitored.
Clean-up of Radioactive Contamination and Legacy Materials or Devices EH&S will notify the PI or department when contamination or unknown/ abandoned RAM or equipment is discovered by EH&S staff. The PI or department will be given reasonable time to complete corrective actions. EH&S will complete the corrective action if necessary. The PI or department may be required to reimburse EH&S for the decontamination and disposal costs incurred.
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N. Other Uses of Radioactive Materials
A number of devices producing ionizing radiation or containing embedded sources are in use at ISU. In accordance with Iowa law, RPDs are registered with the IDPH. RPDs are surveyed by EH&S annually, following major repairs, and as otherwise required. PIs and departments are required to inform EH&S if x-ray systems, x-ray components or other RPDs are purchased, transferred to campus, moved between laboratories, or disposed. Radioiodination Carrier free radioiodine work requires EH&S supervision during the procedure and post iodination bioassay evaluations. EH&S maintains control of all carrier free radioiodine. Contact EH&S to schedule a radio iodination procedure. Animal and Biological Specimen Use Research using live animal models requires the approval of the RSC and IACUC. Application of radiation with animal tissues requires RSC approval only. Radiological research utilizing human, animal and plant pathogens, recombinant or synthetic nucleic acid molecules, genetically modified organisms, and biological toxins requires RSC and IBC approval. Environmental Releases Iowa State University is not licensed for the environmental release of RAM for the purpose of research.
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Appendix I - Guidelines for the Safe Use of Radionuclides
3H – Tritium
14C – Carbon-14
32P – Phosphorus-32
33P – Phosphorus-33
35S – Sulfur-35 51Cr – Chromium-51
55Fe – Iron-55
59Fe – Iron-59
99mTc – Technium-99m 125I – Iodine-125
131I – Iodine-131
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3H TRITIUM
Half - Life Physical Biological Effective 12.3 years 12 days 12 days Radiation Emitted Type Energy (max) Range (max) Beta 18.6 keV Air: 6 mm Tissue: 6 µm External Hazard None Internal Hazard Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 6.4 x 10-2 mrem/µCi 6.4 x 10-2 mrem/µCi (1.73 x 10-11 Sv/Bq) (1.73 x 10-11 Sv/Bq) Annual Limit on Intake: (ALI)* 80 mCi 80 mCi Water Water *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations
• 3H emits the lowest energy beta particle of any commonly use radionuclide.
• 3H contamination cannot be detected directly by any type of portable survey meter.
• Certain 3H compounds, such as tritiated water, readily penetrate gloves and skin in relatively short periods of time.
3 • H is often found in freezer frost/ice.
Radiation Safety Practices • Dosimetry – None • Bioassay – Required when quantities of 25 mCi (925 MBq) or more are used • Shielding – None • Surveys – Wipes, analyzed in an LSC • General – Because 3H contamination is particularly difficult to detect, extra care should be taken in observing contamination control practices. • Two pairs of gloves should be worn, and the outer pair changed frequently, when working with tritiated water. • Tritiated water should be used in a fume hood.
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14C CARBON-14
Half - Life Physical Biological Effective 5,730 years 10 days 10 days Radiation Emitted Type Energy (max) Range (max) Beta 156 keV Air: 24 cm TissueL 0.28 mm External Hazard As a skin contaminant only Internal Hazard
Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 2.1 mrem/µCi 2.4 x 10-2 mrem/µCi (5.64 x 10-10 Sv/Bq) (6.36 x 10-12 Sv/Bq)
CO2 Annual Limit on Intake: (ALI)* 2 mCi 200 mCi
CO2 * ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations • None
Radiation Safety Practices • Dosimetry – None
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – None
• Surveys – Wipes analyzed in LSC
• General – Experimental procedures involving the release of 14C labeled carbon dioxide must be conducted in a fume hood or within a sealed chamber vented to a fume hood.
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32P PHOSPHORUS-32
Half - Life Physical Biological Effective 14.3 days 1,157 days (bone) 14.1 days (bone)
Radiation Emitted Type Energy (max) Range (max) Beta 1.71 MeV Air: 6m Tissue: 8 mm Bremsstrahlung 1.71 MeV Infinite (theoretical)
External Hazard 1 meter Surface Dose rate from a 1 mCi 9.1 µrad/hr 780 rads/hr (37 MBq) point source: (.091 µGy/hr) (7.8 Gy/hr) Dose rate to live skin from 1 9.2 rad/Hr µCi/cm2 (.037 MBq/cm2) skin (92 mGy/hr) contamination: Internal Hazard Effective Committed Dose Ingestion Inhalation
Equivalent per Unit Intake: 8.8 mrem/µCi 6.1 mrem/µCi (2.37 x 10-9 Sv/Bq) (1.64 x 10-9 Sv/Bq) Annual Limit on Intake: (ALI)* 600 µCi 900 µCi
*ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations
• 32P emits the highest energy beta particle of any commonly used radionuclide.
• Relatively small quantities of 32P (microcuries) can result in extremely high external dose rates to live skin and underlying tissue when the distance between the source and skin is short (a few centimeters or less).
• The interaction of 32P beta particles with matter can result in the production of high levels of bremsstrahlung which may require the use of lead shielding (this is particularly true if quantities of 10 mCi (370 MBq) or more are used).
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Radiation Safety Practices • Dosimetry – Extremity dosimeters, such as ring badges, maybe required when working with 1 mCi (37 mBq) or more.
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – Plexiglas (1 cm) should be used when working with 1 mCi (37 MBq) or more. Lead may also be required when working with 10 mCi (370 MBq) or more.
• Surveys – GM meter surveys or wipes analyzed in an LSC.
• General – Bare vials of more than 1 mCi of 32P should not be handled directly unless leaded rubber gloves are worn; shielded containers, tongs, or vial/tube racks should be used for manipulating vials of 32P.
• EH&S should be notified immediately of any 32P skin contamination.
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33P PHOSPHORUS-33
Half - Life Physical Biological Effective 25.4 days 1,157 days (bone) 24.9 days (boneO Radiation Emitted Type Energy (max) Range (max) Beta 249 keV Air: 48 cm Tissue: .6mm External Hazard As a skin contaminant only Internal hazard Effective Committed Dose Ingestion Inhalation
Equivalent per Unit Intake: 0.9 mrem/µCi 0.6 mrem/µCi (2.48 x 10-10 Sv/Bq) (1.71 x 10-10 Sv/Bq) Annual Limit on Intake: (ALI)* 6 mCi 8 mCi
*ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C). Special Considerations • None
Radiation Safety Practices • Dosimetry – None
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – None
• Surveys – Wipes analyzed in LSC or GM meter surveys.
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35S SULFUR-35
Half - Life Physical Biological Effective 87.4 days 90 days 44.3 days Radiation Emitted Type Energy (max) Range (max) Beta 167 keV Air: 28 cm Tissue: .3mm External Hazard As a skin contaminant only Internal Hazard Effective Committed Dose Ingestion Inhalation
Equivalent per Unit Intake: 0.4 mrem/µCi 0.3 mrem/µCi (1.21 x 10-10 Sv/Bq) (8.15 x 10-11 Sv/Bq)
Annual Limit on Intake: (ALI)* 10 mCi 20 mCi
*ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations • None
Radiation Safety Practices • Dosimetry – None
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – None
• Surveys – Wipes analyzed in LSC
53 Radioactive Materials
51Cr CHROMIUM-51
Half - Life Physical Biological Effective 27.7 days 616 days 26.6 days Radiation Emitted Type Energy (max) Gamma 320 keV (9.8%) X-Rays 5 keV (22%) External Hazard 1 meter 1 cm Dose rate from a 1 mCi 16 µrad/hr 160 mrad/hr (37 MBq) point source: (0.16 µGy/hr) (1.6 mGy/hr)
Internal Hazard
Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 0.15 mrem/µCi 0 .11 mrem/µCi (3.98 x 10-11 Sv/Bq) (2.95 x 10-11 Sv/Bq) Annual Limit on Intake: (ALI)* 40 mCi 50 mCi *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations • None
Radiation Safety Practices • Dosimetry – Whole body badges may be required when working with quantities greater than 5 mCi (185 MBq).
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – 7.8 mm lead provides 95% attenuation; lead HVL is 1.7 mm.
• Surveys – Scintillation meter surveys; wipes analyzed in an LSC or gamma counter.
54 Radioactive Materials
55Fe IRON-55
Half - Life Phyisical Biological Effective 986.2 days 800 days 441.7 days Radiation Emitted Type Energy (max) Range (max) Gamma 5.9 keV (24.5%) 6.5 keV (3.3%) External Hazard None Internal Hazard Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 0.6 mrem/mCi 2.7 mrem/mCi
(1.64 x 10-10 Sv/Bq) (7.26 x 10-10 Sv/Bq) Annual Limit on Intake: (ALI)* 9 mCi 2 mCi *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations
• 55Fe emits very low gamma rays which can be difficult to detect with a survey meter.
Radiation Safety Practices • Dosimetry – None
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – None
• Surveys – Wipes analyzed in an LSC or gamma counter.
• General – Because 55Fe contamination is particularly difficult to detect, extra care should be taken in observing contamination control practices.
55 Radioactive Materials
59Fe IRON-59
Half - Life Physical Biological Effective 44.6 days 800 days 44.2 days Radiation Emitted Type Energy (max) Beta 273 keV (45.2%) 466 keV (53.1%) Gamma 1.099 MeV (56.5%) 1.292 MeV (43.2%) External Hazard 1 meter 1 cm Dose rate from a 1 mCi 0.66 mrad/hr 6.6 rad/hr (37 MBq) point source: (6.6 mGy/hr) (66 mGy/hr) Internal Hazard
Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 6.7 mrem/µCi 14.8 mrem/µCi (1.81 x 10-9 Sv/Bq) (4.0 x 10-9 Sv/Bq) Annual Limit on Intake: (ALI)* 800 µCi 300 µCi *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations
• 59Fe emits relatively energetic gamma rays which can pose a significant external hazard. • High external doses to the fingers can result from direct handling of unshielded vials of millicurie quantity 59Fe solutions.
• Because of its relatively long effective half-life, 59Fe has a low annual limit on intake.
Radiation Safety Practices • Dosimetry – Whole body badge required when working with quantities of 100 µCi (3.7 MBq) or more; ring badge required when working with quantities of 1 mCi (37 MBq) or more.
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – 4.5 cm lead provides 95% attenuation; lead HVL is 1.1 cm.
• Surveys – GM meter surveys, wipes analyzed in an LSC or gamma counter.
• General – Bare source vials of 59Fe should be handled with leaded rubber gloves; shielded containers, tongs, or vial/tube racks.
56 Radioactive Materials
99mTc TECHNETIUM-99m Half - Life Physical Biological Effective 0.25 days (6 hours) 1 day 0.2 day (4.8 hours) Radiation Emitted Type Energy (max) Electron 119.5 keV (8.8 %) 137.5 keV (1.9 %) Gamma 140.4 keV (89.1 %) External Hazard 1 meter 1 cm Dose rate from a 1 mCi 0.72 mrad/hr 7.2 rad/hr (37 MBq) point source: (7.2 µGy/hr) (72 mGy/hr)
Internal Hazard Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 0.06 mrem/µCi 0.03 mrem/µCi (1.68 x 10-11 Sv/Bq) (8.8 x 10-12 Sv/Bq) Annual Limit on Intake: (ALI)* 80 mCi 200 mCi *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations
• 99mTc emits relatively energetic gamma rays which can pose a significant external hazard.
• High external doses to the fingers can result from direct handling of unshielded vials of millicurie quantity 99mTc solutions.
• Because of its relatively short effective half-life,99m Tc has a relatively large annual limit on intake.
Radiation Safety Practices • Dosimetry – Whole body badge required when working with quantities of 100 µCi (3.7 MBq) or more; ring badge required when working with quantities of 1 mCi (37 MBq) or more.
• Bioassay – Required for individuals involved in spills or other incidents where significant uptake is suspected.
• Shielding – 2.1 mm lead provides 95% attenuation; lead HVL is 0.5 mm.
• Surveys – NaI meter surveys, wipes analyzed in an LSC or gamma counter.
• General – Unshielded source vials of 99mTc should be handled with leaded rubber gloves; shielded containers, tongs, or vial/tube racks.
57 Radioactive Materials
125I IODINE-125
Half - Life Physical Biological Effective 60.1 days 138 days 41.9 days Radiaiton Emitted Type Energy (max) Gamma 35 keV (7%) X-rays 27-32 keV (138%) Conversion and Auger Electrons 3.2-35 keV (156-0.7%) External Hazard 1 meter 1 cm Dose rate from a 1 mCi 0.14 mrad/hr 1.4 rad/hr (37 MBq) point source: (1.4 µGy/hr) (14 mGy/hr) Internal Hazard
Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 1.27 rem/µCi 0.8 rem/µCi (3.44 x 10-7 Sv/Bq) (2.16 x 10-7 Sv/Bq) Annual Limit on Intake: (ALI)* 40 µCi 60 µCi *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations • Volatilization of iodine from NaI solutions and from solutions of certain labeled compounds is a major concern.
• Gaseous iodine is always present above solutions of NaI in proportion to the pH and temperature of the solution (the amount of gaseous iodine increases as the pH decreases below 9 and as the temperature falls to the freezing point of the solution).
• Internal radiation dose from radioiodine may result from inhalation, ingestion, or absorption through the skin.
• Seventy-five percent of the soluble radioiodine inhaled will be taken up by the body and thirty percent of this activity will accumulate in the thyroid.
• High external doses to the fingers can result from direct handling of unshielded vials of millicurie quantity 125I solutions.
Radiation Safety Practices • Special – EH&S provides onsite monitoring of all radioiodinations. This includes monitoring the set-up of a charcoal filtered glove box within the laboratory‘s fume hood and a “double glove tape up“ procedure for the researcher.
• Dosimetry – Whole-body dosimeter required when working with quantities greater than 5 mCi
58 Radioactive Materials
(185 MBq).
• Bioassay – Thyroid scan required within 24 to 96 hours for each individual performing a radioiodination or any individual who may have come in contact with volatile 125I compounds.
• Shielding – 0.8 mm lead provides 95% attenuation. Lead HVL is 0.017mm.
• Surveys – Scintillation meter surveys; wipes analyzed in an LSC or gamma counter.
• General – All work with potentially volatile 125I labeled compounds must be conducted in a fume hood (quantities of 10 µCi or less of relatively stable compounds such as labeled proteins may be used safely on the open bench).
¤¤NaI in NaOH solutions should not be acidified or frozen.
¤¤Researchers working with volatile 125I compounds should double-glove, changing the outer pair of gloves frequently.
¤¤Emergency procedures for potential releases of volatile radionuclides (found on page 26 and on the laboratory wall chart) should be reviewed by the researcher before performing an iodination.
¤¤Sodium thiosulfate solution should be utilized to stabilize any spilled 125I before decontamination procedures are initiated.
¤¤Bare source vials of 125I should not be handled directly unless leaded rubber gloves are worn.
¤¤Shielded containers, tongs, or vial/tube racks should be used for manipulating vials of millicurie quantity 125I.
59 Radioactive Materials
131I IODINE-131 Half - Life Physical Biological Effective 8.0 days 138 days 7.6 days Radiation Emitted Type Energy (max) Beta 606 keV (89.3%) Gamma 364 keV (81.2%) 637 keV (7.3%) External Hazard 1 meter 1 cm Dose rate from a 1 mCi 0.28 mrad/hr 2.8 rad/hr (37 MBq) point source: (2.8 µGy/hr) (28 mGy/hr) Internal Hazard Effective Committed Dose Ingestion Inhalation Equivalent per Unit Intake: 53.3 mrem/ µCi 32.9 mrem/ µCi (1.44 x 10-8 Sv/Bq) (8.89 x 10-9 Sv/Bq) Annual Limit on Intake: (ALI)* 30 µCi 50 µCi *ALIs expressed are from Appendix B, Table 1 – Iowa Administrative Code 641.40 (136C).
Special Considerations • Volatilization of iodine from NaI solutions and from solutions of certain labeled compounds is a major concern.
• 131I emits relatively energetic gamma rays which can pose a significant external hazard. • High external doses to the fingers can result from direct handling of unshielded vials of millicurie quantity 131I solutions.
• Because 131I is concentrated in the thyroid, it has a low annual limit on intake.
Radiation Safety Practices • Dosimetry – Whole body badge required when working with quantities of 100 µCi (3.7 MBq) or more; ring badge required when working with quantities of 1 mCi (37 MBq) or more.
• Bioassay – Required for individuals involved in incidents where significant uptake is suspected.
• Shielding – 1.3 cm lead provides 95% attenuation; lead HVL is 0.3 cm.
• Surveys – GM meter surveys, wipes analyzed in an LSC or gamma counter.
• General – Bare source vials of 131I should be handled with leaded rubber gloves, shielded containers, tongs, or vial/tube racks.
60 Radioactive Materials
Appendix II - Dictionary and Glossary Absorbed Dose – the amount of energy imparted to matter by ionizing radiation per unit mass of irradiated material. The unit of absorbed dose is the rad, which is 100 ergs/gram. Absorption – the phenomenon by which radiation imparts some or all of its energy to any material through which it passes. Activation – the process of making a material radioactive by bombardment with neutrons, protons, or other nuclear radiation. Activity – the rate of disintegration or transformation or decay of radioactive material. The units of activity are the becqueral (bq) and the curie (Ci). Acute Exposure – the absorption of a relatively large amount of radiation (or intake of radioactive material) over a short period of time. Acute Health Effects – prompt radiation effects (those that would be observable within a short period of time) for which the severity of the effect varies with the dose, and for which a practical threshold exists. Agreement State – any state with which the U.S. Nuclear Regulatory Commission has entered into an effective agreement concerning the licensing of by-product material. Iowa is an agreement state and regulates the safe uses of radiation and by-product material within its boundary. ALARA (acronym for As Low As Reasonably Achievable) – making every reasonable effort to maintain exposures to radiation as far below the dose limits as is practical, consistent with the purpose for which the licensed activity is undertaken, taking into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, and other societal and socioeconomic considerations, and in relation to utilization of nuclear energy and licensed materials in the public interest. Alpha Particle – a strongly ionizing particle emitted from the nucleus during radioactive decay having a mass and charge equal in magnitude to a helium nucleus, consisting of 2 protons and 2 neutrons with a double positive charge. Annual Limit on Intake (ALI) – the derived limit for the amount of radioactive material taken into the body of an adult worker by inhalation or ingestion in a year. ALI is the smaller value of intake of a given radionuclide in a year by a reference person that would result in a committed effective dose equivalent of 5 rem (0.05 Sv) or a committed effective dose equivalent of 50 rem (0.5 Sv) to any individual organ or tissue. Attenuation – the process by which a beam of radiation is reduced in intensity when passing through some material. It is the combination of absorption and scattering processes and leads to a decrease in flux density of the beam when projected through matter. Audit – the periodic examination of the radiation safety program related to the possession, use, storage, transfer, & disposal of licensed material or devices. Background Radiation – ionizing radiation arising from radioactive material other than the one directly under consideration. Background radiation due to cosmic rays and natural radioactivity is always present. There may also be background radiation due to the presence of radioactive substances in other parts of the building, in the building material itself, etc. Becquerel (Bq) – unit of activity in the SI system equal to 1 disintegration per second. 1 becquerel = 2.703 x 10-11 Ci or 2.703 x 10-8 mCi 1 mCi=3.7 x 107 Bq Beta Particle – charged particle emitted from the nucleus of an atom during radioactive decay. A negatively
61 Radioactive Materials charged beta particle is identical to an electron. A positively charged beta particle is called a positron. Bioassay – the determination of kinds, quantities or concentrations, and, in some cases, the locations of radioactive material in the human body, whether by direct measurement (in vivo counting) or by analysis and evaluation of materials excreted or removed from the human body. Body Burden – the amount of radioactive material which if deposited in the total body will produce the maximum permissible dose rate to the critical organ. Bremsstrahlung – electromagnetic (X-ray) radiation produced by the deposition of charged particles in matter. Usually associated with energetic beta emitters, such as 32Phosphorus. Calibration – determination of variation from standard, or accuracy, of a measuring instrument to ascertain necessary correction factors. Charged Particle – an ion. An elementary particle carrying a positive or negative electric charge. Chronic Exposure – the absorption of radiation (or intake of radioactive materials over a long period of time), i.e., over a lifetime. Committed Dose Equivalent – the dose equivalent to organs or tissues of reference that will be received from an intake of radioactive material by an individual during the 50-year period following the intake. Committed Effective Dose Equivalent – the sum of the products of the weighting factors applicable to each of the body organs or tissues that are irradiated and the committed dose equivalent to these organs or tissues. Contamination, Radioactive – deposition of radioactive material in any place where it is not desired, and particularly in any place where its presence may be harmful. The harm caused may be a source of excessive exposure to personnel or the validity of an experiment or a procedure. Controlled Area – an area, outside of a restricted area but inside the site boundary, access to which can be limited by the licensee for any reason. Count – the external indication of a device designed to enumerate ionizing events. It may refer to a single detected event or to the total registered in a given period of time. The term is often erroneously used to designate a disintegration, ionizing event, or voltage pulse. Critical Organ – the organ or tissue, the irradiation of which will result in the greatest hazard to the health of the individual or his descendants. Curie – the quantity of any radioactive material in which the number of disintegrations is 3.7 x 1010 per second. Abbreviated Ci. Decay, Radioactive – disintegration of the nucleus of an unstable nuclide by the spontaneous emission of charged particles and/or photons. Decontamination – the reduction or removal of contaminating radioactive material from a structure, area, object, or person. Decontamination may be accomplished by (1) treating the surface to remove or decrease the contamination, (2) letting the material stand so that the radioactivity is decreased as a result of natural decay, and (3) covering the contamination to shield or attenuate the radiation emitted. Deep Dose Equivalent – applies to external whole-body exposure and is the dose equivalent at a tissue depth of one centimeter (1000 mg/cm2 ). Deterministic Effect - is an effect which has a threshold dose and the severity of the observed effect increases with dose. Dose or Radiation Dose – a generic term that means absorbed dose, dose equivalent, effective dose equivalent, committed dose equivalent, committed effective dose equivalent, or total effective dose
62 Radioactive Materials equivalent, as defined in other paragraphs of this section. Dose Rate – the radiation dose delivered per unit of time. Measured, for example, in rem per hour. Dosimeter – a portable instrument for measuring and registering the total accumulated exposure to ionizing radiation. (see dosimetry) Dosimetry – the theory and application of the principles and techniques involved in the measurement and recording of radiation doses. Its practical aspect is concerned with the use of various types of radiation instruments with which measurements are made. (see fi lm badge; thermoluminescent dosimeter; Geiger- Mueller counter) Effective Dose Equivalent – the sum of the products of the dose equivalent to the organ or tissue and the weighting factors applicable to each of the body organs or tissues that are irradiated. Efficiency – (radiation detection instrument) a measure of the probability that a count will be recorded when radiation is incident on a detector. Usage varies considerably so be aware of which factors (window, transmission, sensitive volume, energy dependence, etc.) are included in a given case. Efficiency refers to the percent of total activity present for a given nuclide detected by the radiation detection instrument being used. Electron – negatively charged elementary particle which is a constituent of every neutral atom. Its unit of negative electricity equals 4.8 x 10-19 coulombs. Its mass is 0.00549 atomic mass units. Electron Volt – a unit of energy equivalent to the amount of energy gained by an electron in passing through a potential difference of 1 volt. Abbreviated eV. Radioisotopic energy is typically measured in MeV (million electron volts). Erg – the unit of energy or work in the centimeter-gram-second system; the work performed by a force acting over a distance of one centimeter so as to result in a one gram mass being accelerated at a rate of one centimeter per second each second. Exposure – (1) being exposed to ionizing radiation or radioactive material, (2) a measure of the ionization produced in air by x-ray or gamma radiation. It is the sum of the electrical charges on all ions of one sign produced in air when all electrons liberated by photons in a volume element of air are completely stopped in air, divided by the mass of air in the volume element. The special unit of exposure is the Roentgen. Extremity – hand, elbow, arm below the elbow, foot, knee, or leg below the knee. Eye Dose Equivalent – applies to the external exposure of the lens of the eye and is taken as the dose equivalent at a tissue depth of 0.3 centimeter (300 mg/cm² ). Film Badge – a packet of photographic film used for the approximate measurement of radiation exposure for personnel monitoring purposes. The badge may contain two or more films of differing sensitivity, and it may contain filters which shield parts of the film from certain types of radiation. Fission - the splitting of a nucleus into at least two other nuclei and the release of a relatively large amount of energy. Two or three neutrons are usually released during this type of transformation. Gamma Ray – very penetrating electromagnetic radiation of nuclear origin. Except for origin, identical to X-ray. Geiger-Mueller (G-M) - Counter a radiation detection and measuring instrument. It consists of a gas- filled tube containing electrodes, between which there is an electrical voltage but no current flowing. When ionizing radiation passes through the tube, a short, intense pulse of current passes from the negative electrode to the positive electrode and is measured or counted. The number of pulses per second measures the intensity of radiation.
63 Radioactive Materials
Gray (Gy) – the SI unit of absorbed dose. One Gray is equal to one joule per kilogram (100 rad). Half-Life, Biological – time required for the body to eliminate 50% of a dose of any substance by the regular processes of elimination. This time is approximately the same for both stable radionuclides and radionuclides of a particular element. Half-Life, Effective – time required for a radioactive nuclide in a system to be diminished by 50% as a result of the combined action of radioactive decay and biological elimination. Effective half-life = Biological half-life x Radioactive half-life / Biological half-life + Radioactive half-life Half-Life, Radioactive – time required for a radioactive substance to lose 50% of its activity by decay. Each radionuclide has a unique half-life. Half Value Layer – the thickness of any specified material necessary to reduce the intensity of an X-ray or gamma ray beam to one-half its original value. Health Physics – a term in common use for that branch of radiological science dealing with the protection of personnel from harmful effects of ionizing radiation. High Radiation Area – an area, accessible to individuals, in which radiation levels could result in an individual receiving a dose equivalent in excess of 100 mrem (1 mSv) in one hour at thirty centimeters from the radiation source or from any surface that the radiation penetrates. Hot Spot – the region in a radiation/contamination area in which the level of radiation/contamination is noticeably greater than in neighboring regions in the area. Individual Monitoring Devices – devices designed to be worn by a single individual for the as-sessment of dose equivalent such as film badges, thermoluminescent dosimeters (TLDs), pocket ionization chambers, and personal air sampling devices. Inverse Square Law – the intensity of radiation at any distance from a point source varies inversely as the square of that distance. For example: if the radiation exposure is 100 R/hr at 1 inch from a source, the exposure will be 0.01 R/hr at 100 inches. Ion – an atom that has too many or too few electrons, causing it to be chemically active; such as an electron that is not associated (in orbit) with a nucleus. Ions may be positively or negatively charged, and vary in size. Ionization is the process by which a neutral atom or molecule acquires either a positive or a negative charge. An ionization chamber is an instrument designed to measure the quantity of ionizing radiation in terms of the charge of electricity associated with ions produced within a defined volume. Ionizing Radiation – alpha particles, beta particles, gamma rays, X-rays, neutrons, high speed electrons, high speed protons, and other particles or electromagnetic radiation capable of producing ions. Isotopes – nuclides having the same number of protons in their nuclei, and hence having the same atomic number, but differing in the number of neutrons, and therefore in the mass number. Almost identical chemical properties exist between radionuclides of a particular element. Joule – the meter-kilogram-second unit of work or energy, equal to the work done by a force of one Newton when its point of application moves through a distance of one meter in the direction of the force. Labeled Compound – a compound consisting, in part, of labeled molecules. By observations of radioactivity or isotopic composition this compound or its fragments may be followed through physical, chemical or biological processes. Late Health Effects – are effects the exhibit themselves a period of years after an exposure. The incidence is generally dependent on the radiation dose, dose rate, age at the time of the exposure Licensed Material – source material, special nuclear material, or by-product material received,
64 Radioactive Materials possessed, used, transferred or disposed of under a general or specific license issued by the Nuclear Regulatory Commission or an Agreement State. Licensee – the holder of the license. Limits – the permissible upper bounds of radiation exposures, contamination or releases.. Luxel® Dosimeter – a dosimetry badge introduced by Landauer, Inc. that uses optically stimulated luminescence of a special aluminum oxide phosphor. A laser light source is used to stimulate luminescence in much the same way heat is used to stimulate luminscence in a thermoluminescent dosimetry (TLD) badge. The light output is then related to the badge‘s radiation dose. Member of the Public – an individual , except when that individual is receiving an occupational dose. Microcurie (µCi) – a one-millionth part of a curie. (1/1,000,000), (.000001 Ci), (see curie) Millicurie (mCi) – a one-thousandth of a curie. (1/1000), (.001 Ci), (see curie) MilliRoentgen (mR) – a sub-multiple of the Roentgen equal to one-thousandth (1/1000) of a Roentgen. (see Roentgen) Monitoring – the measurement of radiation levels, concentrations, surface area concentrations or quantities of radioactive material and the use of the results of these measurements to evaluate potential exposures and doses. NARM – accelerator-produced radioactive material. It does not include by-product, source, or special nuclear material. Natural Radiation – ionizing radiation, not from man-made sources, arising from radioactive material other than the one directly under consideration. Natural radiation due to cosmic rays, soil, natural radiation in the human body and other sources of natural radioactivity are always present. The levels of the natural radiation vary with location, weather patterns and time to some degree. Neutron – elementary particle with a mass approximately the same as that of a hydrogen atom and electrically neutral. It has a half-life in minutes and decays in a free state into a proton and an electron. Non-Removable Contamination – contamination adhering to the surface of structures, areas, objects or personnel and will not readily be picked up or wiped up by physical or mechanical means during the course of a survey or during decontamination efforts. Nuclear Density Gauge – a testing device, usually fixed in place and non-mobile, containing at least one sealed source of radioactive material, used to measure the density and composition of the test material. Nuclear Regulatory Commission (NRC) – an independent federal regulatory agency responsible for licensing and inspecting nuclear power plants, universities and other facilities using radioactive materials. Nucleus – the small, central, positively charged region of an atom that carries essentially all the mass. Except for the nucleus of ordinary (light) hydrogen, which has a single proton, all atomic nuclei contain both protons and neutrons. The number of protons determines the total positive charge, or atomic number; this is the same for all the atomic nuclei of a given chemical element. The total number of neutrons and protons is called the mass number. Nuclide – a species of atom characterized by its mass number, atomic number, and energy state of its nucleus, provided that the atom is capable of existing for a measurable time. Occupational Dose – the dose received by an individual in the course of employment in which the individual‘s assigned duties involve exposure to radiation and to radioactive material from licensed and unlicensed sources of radiation, whether in the possession of the licensee or other person. Occupational dose does not include dose received from background radiation, as a patient from medical practices,
65 Radioactive Materials from voluntary participation in medical research programs, or as a member of the general public. Photon – a quantum (or packet) of energy emitted in the form of electromagnetic radiation. Gamma rays and X-rays are examples of photons. Pig – a container (usually lead) used to ship or store radioactive materials. The thick walls protect the person handling the container from radiation. Large containers are commonly called casks. Portable Gauge – an evaluation device containing at least one sealed source of radioactive material that can be transported or carried to a test location. See Nuclear Density Gauge. Positron – particle equal in mass, but opposite in charge, to the electron; a positive charge. Protective Barriers – barriers of radiation absorbing material, such as lead, concrete, plaster, and plastic, that are used to reduce radiation exposure. Proton – an elementary nuclear particle with a positive electric charge located in the nucleus of an atom. Public Dose – the dose received by a member of the public from exposure to radiation and to radioactive material released by a licensee, or to another source of radiation either within a licensee‘s controlled area or in unrestricted areas. It does not include occupational dose or doses received from background radiation, as a patient from medical practices, or from voluntary participation in medical research programs. Quality Factor – a modifying factor that is used to derive dose equivalent from absorbed dose. It corrects for varying risk potential due to the type of radiation. Rad – the special unit of absorbed dose. One rad is equal to an absorbed dose of 100 ergs/gram. Radiation Area – an area, accessible to individuals, in which radiation levels could result in an individual receiving a dose equivalent in excess of 0.005 rem (0.05 mSv) in one hour at thirty centimeters from the radiation source or from any surface that the radiation penetrates. Radiography – the making of shadow images on photographic film by the action of ionizing radiation. Radioisotope – a nuclide with an unstable ratio of neutrons to protons placing the nucleus in a state of stress. In an attempt to reorganize to a more stable state, it may undergo various types of rearrangement that involve the release of radiation. Radiology – that branch of medicine dealing with the diagnostic and therapeutic applications of radiant energy, including X-rays and radionuclides. Radionuclide – a radioactive isotope of an element. Radiosensitivity – the relative susceptibility of cells, tissues, organs, organisms, or other substances to the injurious action of radiation. Radiotoxicity term referring to the potential of an radionuclide to cause damage to living tissue by absorption of energy from the disintegration of the radioactive material introduced into the body. Relative Biological Effectiveness – for a particular living organism or part of an organism, the ratio of the absorbed dose of a reference radiation that produces a specified biological effect to the absorbed dose of the radiation of interest that produces the same biological effect. Rem – the special unit of dose equivalent. The dose equivalent in rems is equal to the absorbed dose in rads multiplied by the quality factor. (1 rem = .01 sievert) Removable Contamination – contamination deposited on the surface of structures, areas, objects or personnel that can readily be picked up or wiped up by physical or mechanical means during the course of a survey or during decontamination efforts. Restricted Area – an area, access to which is limited by the licensee for the purpose of protecting individuals against undue risks from exposure to radiation and radioactive materials. Restricted area
66 Radioactive Materials does not include areas used as residential quarters, but separate rooms in a residential building may be set apart as a restricted area. Roentgen (R) – the quantity of X-ray or gamma radiation such that the associated corpuscular emission per 0.001293 gram of dry air produces, in air, ions carrying one electrostatic unit of quantity of electricity of either sign. Amount of energy is equal to 2.58 x 10-4 coulombs/kg air. The Roentgen is a special unit of exposure. Scintillation Counter – a counter in which light flashes produced in a scintillator by ionizing radiation are converted into electrical pulses by a photomultiplier tube. Sealed Source – radioactive material that is permanently bonded or fixed in a capsule or matrix designed to prevent release and dispersal of the radioactive material under the most severe conditions which are likely to be encountered in normal use and handling. Seivert – the SI unit of any of the quantities expressed as dose equivalent. The dose equivalent in Seivert is equal to the absorbed dose in Gray multiplied by the quality factor. (1 Sv = 100 rem) Shallow Dose Equivalent – applies to the external exposure of the skin or an extremity and is taken as the dose equivalent at a tissue depth of 0.007 centimeter (7 mg/cm2 ) averaged over an area of one square centimeter. Shielding Material – any material which is used to absorb radiation and thus effectively reduce the intensity of radiation, and in some cases eliminate it. Lead, concrete, aluminum, water and plastic are examples of commonly used shielding material. Site Boundary – that line beyond which the land or property is not owned, leased, or otherwise controlled by the licensee. Smear – (smear or swipe test) a procedure in which a swab, e.g., filter paper or cotton tipped applicator, is rubbed on a surface and its radioactivity measured to determine if the surface is contaminated with loose (removable) radioactive material. Specific Activity– total radioactivity of a given nuclide per gram of a compound, element or radioactive nuclide. Stable Isotope – a radionuclide that does not undergo radioactive decay. Survey an evaluation of the radiological conditions and potential hazards incident to the production, use, transfer, release, disposal or presence of radioactive material or other sources of radiation. When appropriate, such an evaluation includes a physical survey of the location of radioactive material and measurements or calculations of levels of radiation, or concentrations or quantities of radioactive material present. Stochastic Health Effects – random radiation effects (those that would be observable after a long period of time) that is dependent upon the radiation dose. Survey – an evaluation of the radiological conditions and potential hazards incident to the use, transfer disposal, or presence of sources of radiation. This evaluation includes a physical survey of the location of radioactive material and measurements of levels of radiation or quantities of radioactive material present. Thermoluminescent Dosimeter (TLD) – crystalline materials that emit light if they are heated after being they have been exposed to radiation. Total Effective Dose Equivalent– the sum of the deep dose equivalent (for external exposures) and the committed effective dose equivalent (for internal exposures). Tracer, Isotopic – the radionuclide or non natural mixture of radionuclides of an element which may be incorporated into a sample to make possible observation of the course of that element, alone or in combination, through a chemical, biological, or physical process. The observations may be made by
67 Radioactive Materials measurement of radioactivity or of isotopic abundance. Unrestricted Area – an area, access to which is neither limited nor controlled by the licensee. Unstable Isotope – a radionuclide. Very High Radiation Area – an area accessible to individuals, in which radiation levels could result in an individual receiving an absorbed dose in excess of 500 rads (5 grays) in one hour at one meter from a source of radiation or from any surface that the radiation penetrates. X-rays – penetrating electromagnetic radiation having wave lengths shorter than those of visible light. They are usually produced by bombarding a metallic target with fast electrons in a high vacuum. In nuclear reactions it is customary to refer to photons originating in the nucleus as gamma rays, and those originating in the extranuclear part of the atom as X-rays. These rays are sometimes called Roentgen rays after their discoverer, W.C. Roentgen.
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