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NRRPT
Question | Answer |
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1. The transmission of characteristic x-rays through the same element filter as the target results in a nearly monoenergetic output of the x-ray tube around: | 17 to 22 keV |
2. A sample of radioactive material is reported to contain 2000 picocuries of activity. Express this value as disintegrations per minute. | 4440 dpm |
3. In the siting of nuclear reactors, the exclusion radius refers to: | the distance downwind from the reactor that a person may receive either a dose of 25 rem to the whole body or 300 rem to the thyroid if he stands there for two hours after the onset of the postulated accident |
4. Germanium-Lithium semiconductor detectors are limited by count rate due to: | the width of the electrical pulses produced |
5. Tissue dose from thermal neutrons is principally a result of: | (n,gamma) reactions with hydrogen and (n,p) reactions with nitrogen |
6. Filters are used in film badges in order to: 1) accelerate beta particles 2) correct for tissue equivalence 3) discriminate between different types of radiation 4) correct for energy dependence of film | 2,3,4 |
7. Of the following cell types, which is LEAST radiosensitive? | nerve cells |
8. Plutonium: | Is very toxic |
9. The dominant external radiation hazard in Fuel cycle facilities requiring work with unshielded forms of uranium is: | beta |
10. In emergency planning, a "protective action guide" is defined as: | the projected dose which warrants protective action to be taken |
11. The units used to express µ/ρ (mu over rho) are: | cm2/g |
12. What would be a good approximation of the quality factor (QF) of the neutrino? | 0 |
13. The quality factor refers to all the following except: | for all radiation sources, the constant factor which relates absorbed dose to dose equivalent |
14. The Department of Transportation (DOT) label Yellow III allows what surface radiation dose rate, when the package is shipped non-exclusive use? | Between 500 µSv per hr and 2000 µSv per hr |
15. According to 10CFR19, all individuals who are employed by a company must receive instruction in the health protection problems associated with excessive exposure to radiation if they are likely to receive: | 5 mSv |
16. What is one of the special units used to express activity of 16. radioactive materials? | Curie |
17. Which particle is considered to be radioactive by itself? | Neutron |
18. Which of the following radionuclides is NOT a naturally occurring radionuclide? | radiation workers have continuous monitoring of their exposure and the work environment is continuously monitored |
19. Which of the following is a Beta emitter? | Uranium-238 |
20. A sample is measured using a proportional counter. 100 counts are observed in seven minutes. What is the counting rate and its associated standard deviation? | 14.3 cpm +/- 1.4 cpm |
21. The primary function of a radiation detecting instrument that operates in the proportional region is to measure: | Alpha, beta, gamma |
22. If the sample plus background is 1600 counts in one minute and the background is 900 counts in one minute, the net count is 700 counts per minute plus or minus ______ counts per minute (1 standard deviation). | 50 |
23. The SI unit for dose equivalent in man is the: | Rem |
24. The non-stochastic ALIs listed in Appendix B to part 20 are designated: | by the letters "NS" after the value |
25. The non-stochastic ALIs listed in Appendix B to part 20 are designated: | with the name of the organ limited by the dose |
26. An adequate Radiation Safety Program is the ultimate responsibility of: | the owner of the licensed facility |
27. Why are the low atomic number materials such as aluminum and organic plastics used to shield against Beta? | Eliminate Bremmsstrahlung |
28. Which of the following statements is NOT correct with regard to the administration of KI to off-site radiological survey team members | KI must be given before the intake starts to have a beneficial effect |
29. Nominal counting efficiencies of a 2 Pi proportional counter for alpha and beta sources, respectively, would be: | 50% and 65% |
30. In the G-M region of a gas filled type detector, the output: | pulse height is independent of the type and energy of the radiation entering the detector |
31. Which of the following statements about fume hoods is INCORRECT? | the gas, water, and electrical appliances should be operated from inside the fume hood |
32. Radioactive atoms that have a neutron to proton ratio that is great will decay by: | beta minus decay |
33. Which one of the following statements is TRUE regarding neutron bubble detectors? | They are affected by temperature |
34. The "working level" (WL) used in the USA and Canada as a unit of radon decay is: | 1 liter air with emission of 1.3 E5 MeV alpha |
35. Which of the following radionuclides is a bone seeker? | Ca-45 |
36. Half-value thickness for 1 MeV photons in lead is approximately 1 cm. A 100 mCi Zn-65 1.12 MeV/photon point source produces a dose rate of 30 mR/hr at 1 meter. What is the exposure rate at 10 cm from this source with the addition of a 5 cm lead shield | 0.02 mR/hr |
37. The average energy required to produce an ion pair in air by x or gamma radiation is: | 33.7 eV |
38. The approximate diameter of an atomic nucleus is: | 1 E-12 cm |
39. Carbon dating is possible because: | the specific activity of Carbon-14 in living organisms is relatively constant through time, but decays after the death of the organism |
40. According to NUREG-0713, which of the following occupations has the highest average annual individual dose? | Industrial Radiography |
41. The underlying principle for radioresponse of a mammalian tissue is called the Law of _________. | Bergonie and Tribondeau |
42. Which of the below quality factors (QF) apply to diagnostic x-rays? | 1 |
43. Radiobiological evidence suggests that, when compared to more uniform irradiation by the same quantity of radioactive material, highly localized beta irradiation of skin, such as from a particle on the skin: | is less likely to cause skin cancer |
44. Proportional counters have gas amplification factors that are: | Greater than 1 |
45. A meter reads 40,000 net cpm and the efficiency of the detector is 40%. How many dpm does this represent? | 100,000 dpm |
46. The maximum allowable radiation level at contact of a package shipped in other than an exclusive use vehicle | 200 mR/hr |
47. A semi-conductor is distinguished from an insulator or conductor by its: | band gap |
48. What is a "neutrino"? | Massless particle |
49. If a radionuclide undergoes eight half-lives, what percentage of the original activity remains? | 0.4% |
50. In a gas filled detector a low voltage potential will increase the time required to collect ions produced by radiation permitting a large number to be neutralized. This process is called: | recombination |
51. You are analyzing a sample containing Na-24 which emits two gamma photons at 2.76 MeV and 1.37 MeV with 100% abundance. On the gamma spectrometer spectrum two additional peaks are seen at 2.25 MeV and 1.74 MeV. These two additional peaks are due to: | escape of one or more air production gammas from the detector |
52. The class “D” in Appendix B to part 20 applies to a range of clearance half lives: | < 10 days in the pulmonary region of the lung |
53. Which of the following is in the order of MOST effective to LEAST effective shielding materials for gamma radiation sources? | lead, iron, concrete, water |
54. For removing radioactive contamination from the skin, your best choice would be: | a mild soap |
55. Which of the following is one function of the ALARA program? | train workers in methods to reduce exposure |
56. Consider a proportional detector operated at a constant voltage. Based only on the statistical fluctuations, which of the following fill gases would you expect to have the lowest percent resolution? | Xe with a W value of 21.9 eV/ion pair |
57. Radioactive atoms that have a neutron to proton ratio that is great will decay by: | alpha decay |
58. The minimum detectable activity for a counting system is: | an indication of the range of energy response |
59. The minimum mass of material which sustains a nuclear chain reaction for a given set of conditions is called: | critical mass |
60. A shield has to be constructed in front of a hot spot to reduce the exposure rate by 80%. The half value layer for the shielding is one-quarter inch. What is the minimum number of shielding thicknesses required? | 3 |
61. What is the most common ionizing radiation hazard associated with antistatic devices? | Alpha |
62. Which of the following naturally occurring radionuclides contribute the most to the annual average background dose equivalent to a member of the U.S. due to ingestion? | K-40 |
63. Cs-134, Cs-137 and Cs-135 are: | isotopes |
64. Assuming a normal cancer fatality rate of 20%, what would be the total probability of developing a fatal cancer for a group of occupationally exposed workers with a 3 in 1,000 probability of contracting a radiation induced fatal cancer. | 203, in 1,000 |
65. Which of the following Regulatory Guides might be of use to a female employee considering declaring pregnancy? | 8.13 |
66. A tissue-equivalent chamber must: | have walls of gthe same mean density as tissue |
67. You work at a nuclear power plant, it is the evening shift and ou are approached by an NRC inspector who wants to know the density thickness of paper protective clothing he observed on a worker. He would like the information by the end of the shift. | Cut out a square piece of material, send it to the chemistry lab to be weighed and divide the weight by the area of the material. |
68. To remain in compliance with 10CFR61, you need to resample your waste streams in all of the situations below EXCEPT: | semi-annually for confirmation |
69. When leak testing an industrial radiography source, the contamination sample should be obtained: | on the inside of the source tube |
70. Quality factor is a function of the | collision stopping power of the radiation in water |
71. The SI unit for radiation absorbed dose is the: | Gray |
72. A light pipe is used in a scintillation counter to: | prevent the light from being trapped in the phosphor |
73. You have received a package containing radioactive material. The highest smearable contamination on the external surface of the package is 3,000 dpm/100 cm2. You should notify: | the final carrier and the NRC Regional office |
74. The following are considered as risks of chronic low-level radiation exposure: 1) Sterility 2) Leukemia 3) Cataracts 4) Skin erythema | 2 |
75. A chemical which has shown some success as an internal chelating agent for plutonium is: | diethylenetriaminepentaacetic acid (DTPA) |
76. A counting rate of 40 cpm is measured in 2 minutes. What is the standard deviation of this counting rate? | +/- 4.5 cpm |
77. The average energy expended to produce an ion pair is called: | W value |
78. The target organ for most transportable long-lived alpha emitters is: | the bone surfaces |
79. Which of the following detectors operates in a voltage region where gas multiplication effects are observed? | proportional counter |
80. A proper average quality factor for estimating the dose equivalent in a radiation field consisting of an unknown spectrum of fast neutrons is: | 10 |
81. What is the ionization region? | the region of voltage over which the saturation current is produced |
82. Technecium-99m is | Artificially produced and does not occur naturally |
83. The function of an “annular kinetic impactor head” is to trap: | Airborne particles |
84. Which of the following bioassay methods may be found in an Uranium facility? | In-Vivo monitoring using sodium iodide detectors In-Vivo monitoring using hyperpure germanium detectors In-Vivo monitoring using phoswich detectors In-Vitro monitoring using urinalysis and fecal analysis |
85. Which of the following radionuclides in soil is major contributor to genetically significant radiation exposure? | Potassium-40 |
86. How does the NRC regulate x-ray machines? | NRC does not regulate x-ray machines |
87. Measurement uncertainty in a radiation measuring device is a function of: | both precision and accuracy in the measurement |
88. The net counts observed from successively counting a sample are plotted on semilog paper, and the plot forms a curved line. It is probable that: | the sample contained more than one radionuclide |
89. The build-up factor in radiation shielding is caused by: | Broad beam conditions |
90. What scintillator material has a high efficiency for alpha measurement and is not especially affected by temperature, humidity, and barometric pressure? | ZnS |
91. In what way can we establish whether or not an individual could exceed some percent of the DAC? | obtain an air sample |
92. An individual living in Denver, Colorado (elevation 5280 ft above sea level) could expect to receive an average annual dose equivalent due to cosmic radiation of approximately: | 50 mrem |
93. You are assigned to count a number of environmental samples. To meet the required LLDs you need to adjust a number of the counting parameters. To increase the LLD value what must you do to: sample size, count time and detector background? | increase sample size, increase count time, reduce background |
94. The exposure rate of the turbine floor of a boiling water reactor plant could be expected to be decreased to less than 1% at least _______________ after shutdown? | five minutes |
95. The primary purpose of a routine tritium urinalysis bioassay is to: | assess the effectiveness of administrative and physical controls of the radiation protection program for tritium |
96. When transporting a Highway Route Controlled Quantity of radioactive material outside of the licensee’s state, notification must be made to: | affected state governors or their designated deputies and the regional DOT offices |
97. Decontamination of a hot cell is most easily accomplished if the hot cell is: | constructed of stainless steel |
98. The following dosimetry should be worn in mixed neutron/beta/gamma field: | albedo TLD, self-reading quartz fiber dosimeter and beta-gamma responsive TLD |
99. The minimum recommended face velocity for a fume hood is: | 125 linear feet per minute |
100. After four half-lives, the original activity of a radionuclide will be reduced by a factor of: | 16 |