Environmental Health & Safety

University of Colorado Boulder


Unsealed Radioisotope Users Refresher Completion Quiz

Please fill out the following information and answer all questions.

  1. Health Physics personnel are available to assist with questions and emergency response involving radioactive materials. During normal business hours, what number would you call to contact Health Physics?

  2. Which radiation is least penetrating of human skin tissue?

  3. Which type of external radiation would be considered the most hazardous, given an equal amount of activity and distance from the source?

  4. The Total Effective Dose Limit, set by the Nuclear Regulatory Commission (NRC), is an amount of radiation which may be received by a radiation worker.

  5. Surveys taken by laboratories using unsealed radioactive materials are required to be taken:

  6. When the distance between a worker and a radioactive source is increased, the amount of radiation received will

  7. If a radiation worker becomes pregnant, she is encouraged to voluntarily

  8. Which type of shielding will reduce the hazard of Bremsstrahlung x-rays which are created by high-energy beta-emitters, such as 32P?

  9. Loose contamination in the laboratory must be controlled so that

  10. During a routine contamination survey of laboratory, Health Physics personel find a lab bench contaminated at the level of 1,200 dpm/100 cm2 of 32P. The area MUST be decontaminated and resurveyed.

  11. Contamination surveys must be performed by laboratory personnel at the following intervals

  12. Radioactive materials may only be ordered using a Purchase Request (PR)/Standing Purchase Order (SPO).

  13. It is acceptable to use biohazard bags to hold radioactive waste.

  14. The annual occupational dose (whole body) limit to radiation workers, set by the NRC, is

  15. Decontamination of laboratory surfaces is best achieved by

  16. Before using a portable radiation survey instrument (such as a geiger counter) you should

  17. Dosimeters should be worn

  18. The reading on a geiger counter is always constant, regardless of the type of radiation monitored, the distance between the instrument probe and the source, and the orientation of the probe with relation to the surface monitored.

  19. The main duty of a principal investigator (P.I.) licensed by the Radiation Safety Committee is to

  20. No eating, drinking, or applying of cosmetics is allowed in a laboratory using radiation, except in designated areas and after washing one’s hands.

  21. The primary use of a dosimeter is to

  22. The principal delayed effect of radiation exposure is the potential of developing cancer.

  23. The risk of radiation induced cancer from occupational exposure is much greater than the risks associated with other events or activities we encounter and accept in our normal day-to-day life.

  24. Disposable equipment such as petri dishes, rubber gloves and razor blades used in experiments which mix radioactive materials with biologically hazardous materials should be disposed of by

  25. It is a good idea to periodically dispose of old isotope vials, especially those containing tritium, in order to reduce the risks from exposure and contamination.

  26. IMPORTANT! If you have worked with radiation at any institution other than the University of Colorado during the past three years, it is your responsibility to notify Health Physics so that your lifetime dose can be tracked. Please answer the questions below before submitting your refresher quiz.

  27. Please list the names and addresses of any institutions where you’ve worked with radiation in the past 3 years. Please include Radiation Safety contacts and the type(s) of radiation you used.