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Section 4: Laboratory Procedures


A. Laboratories Using Unsealed Sources of Radioactive Materials

  1. Isotope Procurement and Storage
    • See Section XI for procedures for ordering isotopes.
    • Keep an up-to-date inventory of radioactive materials at all times. Isotope shipments must be listed by bar code number on the "Summary of Isotope Inventory" form.
    • Store radioisotopes in such a manner as to prevent unauthorized use or removal. Storage must be in a secure area or under lock and key when the laboratory is vacant for any reason.
    • Radioactive materials must not be stored in refrigerators used for food. Radioisotopes must not be stored in any containers in the hallways.
    • Where two or more isotopes are suitable for the same experiment, the less hazardous one should be ordered.

      Examples: Cobalt-59 rather than Cobalt-60, Strontium-85 or 89 rather than Strontium-90.

  2. Training of Personnel
    • Post a concise list of radiation safety procedures in each laboratory.
    • It is the responsibility of the authorized user to ensure that all personnel are properly trained and have signed a copy of the training form before being allowed to work with radioactive materials. Contact the RSO for scheduling a training course. Training should include
      • principles of radiation safety.
      • use of monitoring instruments.
      • protective equipment to be used.
      • how to contact a Radiation Safety Officer.
      • reading of the Radiation Safety Manual; a copy of the manual must be available at all times to laboratory personnel.
      • proper packaging of waste.
      • decontamination procedure.
      • proper record keeping.

  3. Protective Equipment
    • Radiation Monitoring Badges
      • Badges will be provided by the Radiation Safety Officer for persons who have to enter a high radiation area.
      • Badges will be provided for persons working in any area where any person has received over 25% of the maximum permissible quarterly exposure within the past two years.
      • Badges will be provided for any person who, in the judgment of the Radiation Safety Officer, might receive as much as 10% of the maximum permissible exposure for any quarter.

    • A lab coat or apron, safety glasses, and gloves are a minimum requirement and must be worn when handling unsealed sources. Shoes with closed toes are required.
    • Gamma samples producing more than 37.5mrem/hr (3.75 x 10-4 Sieverts/hr) at contact should be handled with tongs. Hard betas such as those from 32P should be handled with tongs if the quantity exceeds 1 millicurie.
    • Fume hood requirements
      • 1 millicurie of non-volatile may be approved for a laboratory without a fume hood.
      • Up to 50 millicurie may be used in a standard fume hood when approved by the Radiation Safety Committee.
      • Over 50 millicuries may be used in a radioisotope fume hood when approved by the Radiation Safety Committee.

  4. Contamination
    • Absorbent paper with waterproof backing shall be used to cover the working surface of tables and hoods used for radioactive materials. Place absorbent surface up.
    • Any worker, who through accident or design causes contamination of working surfaces or equipment, is responsible for decontamination of the same.
    • In the case of extensive or dangerous level of contamination, the Radiation Safety Officer shall be called for advice and assistance.
      • Any wipe sample of 100cm2 which gives a count more than 3 times background indicates that the area should be decontaminated.
      • The Radiation Safety Officer must be notified if a wipe sample indicates more than 10,000 decays per minute per 100cm2 above background. Notification must be in writing.

    • All cases of contamination of persons or laboratory space must be reported to the Authorized User and Radiation Safety Officer.

  5. Monitoring
    • A survey instrument capable of detecting the isotopes in use shall be available in each laboratory.
      • Each laboratory must have a dedicated survey meter. A borrowed meter is not considered responsive to the safety requirement.
      • The survey instrument must have an audible signal not requiring earphones. For laboratories using beta emitter, the instrument must have a thin end window tube.
      • The meter must have an adjustment mechanism so that it can be calibrated.
      • The meter must read in units of rem or sieverts. A count per minute scale does not furnish adequate information for radiation protection.

    • Monitoring instruments must be calibrated at intervals no longer than 12 months.
    • Hands, feet, and clothes shall be monitored before leaving the laboratory after handling radioactive materials.

  6. Transfer of Radioactive Materials
    • Radioactive materials may be transferred from one Authorized User to another Authorized User only after written authorization of the Radiation Safety Officer.
    • Transport of radioactive materials off the campus in private vehicles is not permitted.
    • Isotopes defined for common carrier must be approved by the Radiation Safety Officer before shipment to assure they are properly packaged and all shipping papers are completed.

  7. Surveys
    • A survey including wipe samples and dose rates must be made monthly when radioactive materials are used in the area. (See sample of the survey form in Appendix F.) More frequent surveys should be made as necessary. A record of the results of the monthly survey must be maintained in the laboratory. This record must be available to Radiation Safety personnel (Baylor University or Texas Department of State Health Services) at all times.
    • Deleted (4/12/11)

  8. Waste Disposal
    • Radioactive waste must be properly packaged and labeled for disposal. (See Section VII.)
    • Written authorization is required for disposal by sewer of any radioactive material.

  9. Posting and Labeling
    • Proper signs must be posted in all working and storage areas. (See Section VI "Radiation Warning Signs and Labels".)
    • All containers of radioactive material must be marked with isotope quantity and date. Containers of less than one microcurie being used in the laboratory with the user constantly present are exempt from this requirement.

  10. Miscellaneous Laboratory Rules
    • Only persons with permission from the Authorized User or qualified safety personnel may enter the laboratory.
    • Eating, drinking, and smoking in the laboratory or pipetting by mouth is PROHIBITED.
    • Unnecessary materials should not be taken into the laboratory.
    • Wounds which might contain contamination should be reported immediately to the Authorized User and the Radiation Safety Officer.
    • Volatile or potentially volatile radioactive materials must be handled in a fume hood rated for the prescribed amount of material.
    • Deleted 06/91/2013 (License: L00343 does not allow for more than 50 millicurie Tritium)
    • Routine thyroid measurements are required for persons working with more than 1 millicurie of Iodine-125 or Iodine-131. (See Appendix E.)

B. Installations of X-Ray Producing Devices

  1. All x-ray installations shall comply with the Texas Regulations for Control of Radiation. Also see section IX "Radiation Producing Devices".
  2. All persons must be properly trained before being allowed to operate radiation producing equipment. Evidence or training must be documented and available for inspection.
  3. Post the Texas Department of State Health Services Notice to Employees, BRC Form 203-1. (See Appendix G.)
  4. All proper radiation producing equipment must be surveyed periodically for leaks.
  5. A proper radiation warning sign must be posted at all installations. (See Section VI.)
  6. A concise list of safety procedures must be available at the installation. These instructions should include:
    • who is responsible for the operation of the equipment.
    • safe operating instructions.
    • what monitoring device is to be used during operation.
    • the defining of any laboratory access limitations during operation of the x-ray device.
    • an audible or visual indication of the radiation exposure when the equipment is on.
    • written emergency procedure in case of accident, injury, fire, or inability to normally stop x-ray production.

  7. All persons who might receive more than 25 millirem (2.5 x 10-4 sieverts) in any 1 week must wear a film badge dosimeter.
  8. In general, persons under age 18, (except those enrolled in x-ray training schools under the direct supervision of a qualified doctor of the healing arts) may be exposed to no more than 10 millirem (1.0 x 10-4 sieverts) per week.
  9. The maximum radiation exposure in an uncontrolled area is 2.0 millirem (2.0x 10-5 sieverts) in any 1 hour or 100 millirem (1.0 x 10-3 sieverts) in any 7 consecutive days.
  10. Maximum exposure of workers in a controlled area is in general 100 millirem per week. (See Section V.)
  11. Each radiation generator, except those used solely in the healing arts, which may produce more than 100 millirem in any 1 hour must have a warning signal or light at the generator.
  12. All x-ray producing devices must be registered with the state of Texas.
  13. For rules of specific installations, the Radiation Safety Officer should be consulted. Copies of the State Regulations are available.

C. Sealed Sources

  1. A proper sign must be posted at each installation. (See Section VI.)
  2. A concise list of safety instructions must be posted.
  3. Post Notice to Employees.
  4. Persons who might receive more than 25 millirem in any 1 week must wear a film badge dosimeter.
  5. Exposure levels in any uncontrolled area should not exceed 2 millirem per hour.
  6. Radiation levels in a controlled area should not be such that any person could receive more than 100 millirem in any 1 week.
  7. Persons under 18 must not be exposed to more than 10 millirem per week.
  8. Revised 6/19/13: Some licensed sealed sources must be checked for leakage every calendar quarter. Detection of 0.005 microcuries or more on a wipe test will be taken as evidence that the source is leaking. Leaks must be reported to the Texas Department of State Health Services within 5 days. Sealed sources containing less than 100 microcurie of beta/ gamma or 10 microcuries of alpha emitters do not have to be tested. Consult with the RSO to determine leak check requirements.
  9. Any sealed source which is not fastened to, or contained in an exposure device must have permanently attached to it, a durable tag at least 1 inch square, bearing the radiation symbol and the words "Danger-Radioactive Material Do Not Handle Notify Civil Authorities if Found."
  10. A calibrated survey instrument capable of detecting the radiation in question must be available before any sealed source is utilized.
    • A survey must be conducted after each use to assure that the source has been returned to this shielded container.
    • Each worker must be trained in the use of the survey meter before being allowed to use the source.

  11. No sealed source may be removed from the University campus unless specific authorization is contained in the University license.

D. Miscellaneous Regulations

  1. The Radiation Safety Officer must be notified before any radioactive material or radiation producing device is brought on campus.
  2. The Radiation Safety Officer will provide, upon request, a copy of any individual's exposure to that individual.
  3. Any radioactive material shipped or transported must conform to US Department of Transportation Regulations.
  4. Radioactive materials will not be used in any laboratory where general safety conditions are seriously deficient and might add to the radiation hazard in case of accident. Examples of such conditions are:
    • excessive storage of flammables
    • excessive storage of explosive materials
    • unsecured compressed gas cylinders
    • unsafe experimental techniques
    • excessively cluttered laboratory
    • no safety shower or eye wash

  5. Quantities of radioactive materials or the use of procedures that exceed the laboratory facilities available for safe handling are specifically prohibited.

E. Decommissioning a Radioactive Material Work Area

  1. Decommission to remove a facility or site safely from service and reduce residual radioactivity to a level that permits release of the property for unrestricted use and/or termination of license requirements.
  2. The responsible Authorized User shall notify the Radiation Safety Officer when a designated radiation work area will no longer be used for radioactive material.
    • The Authorized User shall submit a final room survey to the Radiation Safety Officer indicating that the room is acceptable to be released for unrestricted use.
    • Proper radiation safety postings and security shall be maintained until removal is approved by the Radiation Safety Officer.

  3. The Radiation Safety Officer may terminate use of the work area by amending the Radioactive Material License and receiving approval from the Texas Department of State Health Services.
  4. All records of decommissioning shall be maintained in the Department of EHS (RSO files).