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Health and Safety Guide




    Radioactive materials are used primarily within science and engineering departments but may also be found in devices such as smoke detectors, static eliminators and moisture density gauges used in other departments.

    Radioactive materials can be in the form of open sources or sealed sources. An open source of radioactive material is normally used as a tracer in experiments and has the potential for spillage and release if not properly contained. A sealed source is in a form that is permanently bonded or fixed in a capsule or matrix designed to prevent release of the radioactive material.

    The use of radioactive materials is regulated by the federal Nuclear Regulatory Commission (NRC) or the New Jersey Department of Environmental Protection (NJDEP).

    Within the University, the Radiation Safety Committee establishes policies and procedures for the use of radioactive material. To use radioactive material, a principal investigator applies to the Radiation Safety Committee for authorization to use the material in accordance with University, NRC and/or NJDEP regulations. The Health Physics Section of the Office of Environmental Health and Safety (EHS) administers the authorization process, provides services to the Authorized Users, and monitors compliance with federal and state regulations.

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Scope and Application

    This section applies to all persons using radioactive material in any form.

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Program Description

    Any individual/principal investigator planning a new use of radioactive material must first contact a health physicist at EHS to submit an application for authorization to possess and use radioactive material. The applicant is interviewed and advised of the appropriate regulations and internal procedures by a health physicist. The completed application for the use of radioactive material is reviewed and then may be approved/authorized by the Radiation Safety Committee.

    An Authorization Number is issued for specific conditions of radioisotope use, e.g., for a specific isotope, possession limit and type of use. An individual who has been issued Authorization Numbers is known as an Authorized User.

    The Princeton University Radiation Safety Manual for Laboratory Users, which is available from EHS, provides a detailed description of the program elements summarized below. Depending upon the specific circumstances, some or all of the following may apply to the use of radioactive material.

    Exposure Monitoring

    Depending on the specific radioisotope and the amount of radioactivity used in an Authorized Userís laboratory, it may be necessary to monitor radiation exposure of workers in the laboratory.

    EHS administers the radiation exposure monitoring program, provides and exchanges monitors, provides bioassay services, distributes radiation exposure reports, investigates any unusual radiation exposures, maintains permanent exposure records, and administers the Declared Pregnant Worker Program.

    Effluent Monitoring

    Releases of radioactive material to the environment through the sewers and fume hoods must be monitored and reported to regulatory agencies. EHS uses release reports provided by Authorized Users and monitoring data to ensure compliance with effluent limits.

    Radioactive Material Shipments

    Incoming radioactive material packages are surveyed and inspected by EHS prior to delivery to the laboratory.

    EHS provides advice and oversight when packages of radioactive material are shipped from the University to ensure that packages are shipped in compliance with license conditions and Department of Transportation regulations.

    Purchase and Inventory Control

    The inventory of radioactive material at the University and under each Authorized Userís possession must be monitored and controlled to ensure that the University does not exceed its license limit. Consequently, Authorized Users must carefully track all use of radioactive material. In addition, detailed procedures for purchasing radioactive material require that EHS approve all radioisotope purchase orders.


    The Universityís radioisotope security policy generally requires that all radioactive stock materials and sealed sources be stored in a secured container or secured storage area when not in use. A stock material is defined to be radioactive material as provided by the vendor and does not include material withdrawn by a researcher for experimental use.

    Radiation Surveys

    Limiting radiation exposure depends on minimizing radiation levels and controlling contamination. In any area in which radioactive material is stored or used, users must perform frequent and thorough contamination surveys as they work; the Authorized User must ensure that the laboratory is surveyed at set frequencies; and EHS must perform surveys to verify compliance and to ensure that radiation exposure is kept as low as readily achievable.

    Radioactive Waste

    All radioactive waste must be disposed of through the Universityís radioactive waste disposal program, which is overseen by EHS. There are several radioactive waste disposal streams; packaging and disposal procedures and the ultimate route of disposal depend on the radioisotope, its activity and its chemical and physical form. The purpose of the radioactive waste disposal program is to minimize waste volumes, to ensure proper and adequate departmental storage before disposal, and to ensure proper disposal.

    Billing Costs

    EHS, as the billing contact, distributes costs to appropriate departments for radioactive waste disposal and radiation dosimeter badges. Authorized Users may also be required to procure radiation safety equipment such as portable radiation survey meters or pay for improvements to a fume hoodís flow rate, etc.


    All persons who work in a laboratory in which open sources of radioactive material are used, regardless of whether those persons will use radioactive materials or not, must receive initial training by the Health Physics staff and must attend refresher training provided by the Health Physics staff annually. Training is also provided to University support staff who may enter areas where radioactive material is used.

    Laboratory supervisors provide appropriate supplemental training in addition to the mandatory training described above. All radiation workers must satisfy the additional training requirements established by their department and Authorized User.

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Roles and Responsibilities


    • Ensure that new faculty planning to use radioactive material contact EHS for initiation of an authorization application.
    • Ensure that support staff receive appropriate training, including receiving room and building maintenance staff.
    • Plan for waste storage space.
    Authorized User
    • Assure employees attend all required training and keep records of attendance.
    • Bear responsibility for radiation safety, enforcement of Radiation Safety Committee requirements and University, state and federal regulations.
    • Become conversant with and comply with the requirements of the Radiation Safety Manual.
    • Establish appropriate radiation emergency procedures.
    • Submit required reports in a timely manner.
    • Be fully knowledgeable of the specific precautions and handling requirements for each isotope used and of the precautions to be followed with radioisotopes in general.
    • Be familiar with conditions of the Authorized Userís Authorization.
    • Be familiar with and comply with all the relevant procedures of Princeton Universityís radiation safety program, including isotope purchasing and waste disposal procedures.
    • Be familiar with radiation emergency procedures.
    • Attend all required radiation safety training.
    • Provide technical advice on all aspects of radiation safety.
    • Register and calibrate portable survey meters.
    • Review each proposed use of radioactive material with the potential Authorized User.
    • Perform routine periodic and special contamination surveys.
    • Contract with radioactive waste disposal vendor and coordinate all shipments.
    • Contract with personal dosimetry vendor and provide personal dosimeter badges.
    • Monitor and review radiation dose reports and investigate unusual radiation exposures.
    • Provide consultation with pregnant workers, when requested.
    • Provide bioassay services as required.
    • Provide training to radioisotope users and support staff.
    • Approve or disapprove radioisotope purchase orders.
    • Provide effluent monitoring.
    • Audit department program periodically.

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For More Information

    Contact an EHS Health Physicist at 258-5294.

    A Laboratory Radiation Safety Self-Audit Checklist is available through EHS or may be downloaded either as a PDF or a customizable Word document.

    The Princeton University Radiation Safety Manual for Laboratory Users is available through EHS.

    The following references are available through EHS:

    • Princeton Universityís NRC and NJDEP radioactive materials licenses
    • NRC Regulations, Title 10, Code of Federal Regulations
    • NJDEP Administrative Code, Title 7, Chapter 28
    • Department of Transportation (DOT) Regulations
    • Various NRC Regulatory Guides and documents including Regulatory Guide 8.10, Operating Philosophy for Maintaining Occupational Radiation Exposures As Low As is Reasonably Achievable, and Regulatory Guide 8.13, Instruction Concerning Prenatal Radiation Exposure.

    Links to other radiation safety-related web sites are available here.

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