Rules for Working with Radioactive Materials

Determination of policies regarding the use of radioactive isotopes in the Science Center:
The authority to set policies regarding the acquisition and use of radioactive materials within the Science Center resides in the Radiation Safety Committee which operates under the license granted to Wellesley College by the Nuclear Regulatory Commission.

Copies of the license and Code of Federal Regulations are on file with the Radiation Safety Officer (RSO).

General Information for all individuals in the Science Center.

  • Do not enter areas, open refrigerators, or tamper with containers marked with the radiation hazard sign, unless authorized.
  • All radioactive isotopes must be stored in a secure area when not in use. If they are stored in a research laboratory, the lab must be locked when not in use. If the isotope is stored in refrigerators or freezers in teaching labs or hallways, the refrigerator or freezer must be locked.
  • All incoming shipments of isotopes must be surveyed for surface contamination before delivery to laboratories. This is done by the PI responsible for the shipment.
  • Violation of any of the license conditions or pertinent Federal Regulations can result in loss of license privileges.
  • Please address any questions regarding the use or misuse of radioisotopes to the Radiation Safety Officer or the Science Center Office (X3000).

A video tape on radiation safety is on reserve in the Library. All new users are required to view this lecture.

Responsibilities of Faculty Supervisors with Regard to the Use of Radioisotopes:

  • You may not work with radioisotopes until your experimental protocol has been approved by the Radiation Safety Committee.  If you are not currently a licensed user, your work must be supervised by a licensed user.
  • If an experiment involves the use of quantities of P32 equal to or greater than 1 millicurie, you must contact the Radiation Safety Officer and refer to Special Precautions for Those Using Milicurie Quantities P32 prior to any experimentation.
  • If your experiment involves using 1 millicurie or more P32 it must be conducted in the radioisotope room.
  • Ensure that your students read the appropriate sections of the Wellesley College Laboratory Safety Manual before conducting any experiments with radioisotopes.
  • Students must be instructed on the use and location of personal monitoring devices and the maximum dose rate allowed by law. See Maximum Doses.
  • When appropriate the faculty member must ensure that film badges are available for personal and student use and that adequate records are maintained.
  • It is the faculty members responsibility to ensure that wipe tests are being conducted and that adequate records are maintained and forwarded to the Radiation Safety Officer.
  • A current inventory of isotopes under the control of a given supervisor must be maintained.

Procedures for Experiments Utilizing Radioisotopes:

  • Do not smoke, eat, or drink in radiation areas.
  • Do all experiments on plastic backed absorbent paper or a containment tray. When using H3 or C14, use a containment tray instead of the absorbent paper.
  • Do not pipet radioactive solution by mouth.
  • Wear gloves and a lab coat when handling radioactive materials, if they are in such a form as to cause contamination of hands or clothing.
  • All beakers, test tubes, and flasks containing radioactive materials, while in use in the laboratory, must remain under the constant control of the user., and appropriate labels must be affixed.
  • Dispose of radioactive wastes properly. See Disposal of Radioactive Waste.
  • Survey skin, hair, and clothing after handling unsealed radioactive material, and wash hands before leaving the laboratory.
  • Do not handle radioactive source by hand, unless you are sure that the contact dose is within permissible limits and that the source is not contaminated externally.

Emergency Procedures:


  • Begin decontamination procedures as soon as possible. Attempt to reduce skin contamination to less than 0.1 mrad/hr. Call infirmary (ext. 2810) if help or advice is wanted, or if skin contamination exceeds 0.1 mrad/hr.
  • If decontamination is unsuccessful with soap and water or other harmless laboratory solvents, use "Isoclean" or "Count-off".
  • Notify the Radiation Safety Officer of any incident requiring the use of decontamination.


  • Immediately wash the wound under a strong stream of water.
  • Report to the infirmary as soon as possible, specifically informing the receptionist and nurse the radioactive material was involved.


If radioactive material is spilled on bench surfaces, equipment, or floor, it must be cleaned up immediately. Tracking of material through the Science Center would be a logistical nightmare to clean up.

    Maximum Permissible Radiation Doses

    The values listed below are specified in the Atomic Energy Commission's Regulation 10 CFR Part 20 "Standards For Protection Against Radiation". Also, the values listed are consistent with those specified in the "Rules and Regulations To Control Radiation Hazards" of the Massachusetts Department of Public Health.

    Maximum Permissible Doses for Radiation Workers:

    Except as provided in Paragraph b, radiation doses shall not exceed the following:

    Annual rem limit

    • Deep-dose equivalent (external exposure whole body) 50
    • Eye-dose equivalent (external exposure to lens of the eye) 15
    • Shallow-dose equivalent (external exposure to skin or an extremity) 50
    • Effective dose equivalent (exposure to organs) 5


    An individual may exceed "a .1." provided that it is authorized by the Radiation Safety Officer and that:

    • During any calendar quarter his whole body dose from all sources of radiation does not exceed 3 rems; and
    • The accumulated occupational dose does not exceed 5(N 18) rem, where nNn equals age in years at the individual's last birthday; and
    • There is on file an appropriate record (as specified in 10 CFR 20, section 20.101) of the individual's accumulatet occupational whole body dose.


    Maximum Permissible Doses for Minors, and Non-Radiation Workers:

    One tenth of values listed in I.a.