NRRPT EXAM REVIEW EXAM QUESTIONS AND ANSWERS
Effects of acute radiation exposure on the central nervous system can be
observed at doses of: - CORRECT ANSWER✅✅1000 rads.
Genetic effects produced by radiation in males are dependent on:
1. State of germ cell development
2. LET of the radiation
3. Interval between the exposure and conception - CORRECT ANSWER✅✅1,2,3
What is the "threshold" of radiation dose effects? - CORRECT ANSWER✅✅The dose of radiation below
which there are no effects whatsoever on the body
The three naturally-occurring radioactive decay chains are: - CORRECT ANSWER✅✅Thorium, Actinium,
Uranium
Which radionuclide is NOT a naturally occurring radionuclide? - CORRECT ANSWER✅✅Cs-137
The dose equivalent to the U.S. population from all man-made sources of
radiation is given by the NCRP as approximately - CORRECT ANSWER✅✅60 mrem/year
Most of the dose received by man from man-made sources of radiation is due to: - CORRECT
ANSWER✅✅medical applications of radiation and radioactive materials.
One Roentgen is equal to: - CORRECT ANSWER✅✅2.58 x 10-4 coulomb/kg air.
For an isotope having an allowed concentration of 1 x 10-5 µCi /cc, what is the minimum discharge time
to not exceed the concentration when 1.5 curies of activity are discharged into a stream having a flow
rate of 140,000 gallons/hour? (1 gallon = 3785.6 cc). - CORRECT ANSWER✅✅283 hours
,The energy absorbed by 1 gram of air exposed to 1 Roentgen of gamma rays is equivalent to: - CORRECT
ANSWER✅✅87 ergs.
All of the following statements about atomic structure are true EXCEPT: - CORRECT
ANSWER✅✅Electrons, protons, and neutrons are all of about equal mass
The radius of the nucleus of an atom as compared to the atom as a whole is: - CORRECT
ANSWER✅✅some 10,000 times smaller.
Isotopes are: - CORRECT ANSWER✅✅forms of the same element containing different numbers of
neutrons.
What are isotones? - CORRECT ANSWER✅✅nuclides with the same number of neutrons
Emission of a negatively charged beta particle results from the transformation of: - CORRECT
ANSWER✅✅a neutron into a proton.
Following electron capture, the following processes may occur:
1. Z increases by 1
2. Z decreases by 1
3. Characteristic x-rays are emitted
4. Auger electron emission - CORRECT ANSWER✅✅2,3,4
A technician surveys a shielded pure beta-emitting source and obtains a measurement of 0.2 R/hr. If all
beta particles are shielded, the reading is caused by: - CORRECT ANSWER✅✅Bremsstrahlung.
The dose to tissue from 6 MeV neutrons is delivered primarily by: - CORRECT ANSWER✅✅recoil
protons.
In the interaction of thermal neutrons with tissue, the major dose is from: - CORRECT ANSWER✅✅the
H-1(n,gamma)H-2 reaction
, The average energy required to produce an ion pair in air by x or gamma radiation is which of the
following? - CORRECT ANSWER✅✅33.7 eV
Which of the organ systems is the MOST radiosensitive - CORRECT ANSWER✅✅Bone marrow
Which of the following are considered risks of chronic low-level radiation exposure?
1. Sterility
2. Leukemia
3. Cataracts
4. Skin erythema - CORRECT ANSWER✅✅2
Which radionuclide is a bone seeker? - CORRECT ANSWER✅✅Ca-45
"Below a certain radiation dose, no effects whatsoever occur in the human
body." This statement supports which dose/effect theory? - CORRECT ANSWER✅✅Threshold
Why are the dose equivalent limits for occupationally exposed persons so
much higher than those set for members of the general public? - CORRECT ANSWER✅✅The number of
radiation workers is very low compared to the population, so the total risk is very small
If a linear relationship between somatic effects of radiation and absorbed dose is assumed, the number
of additional cancer deaths to be expected per million persons per rad is: - CORRECT
ANSWER✅✅greater than 100
Why is a child more radiosensitive than an adult - CORRECT ANSWER✅✅A child's cells are multiplying
more rapidly
The Systeme Internationale units Gray and Sievert represent the same
respective quantities in which of the following? - CORRECT ANSWER✅✅Rad and rem
Effects of acute radiation exposure on the central nervous system can be
observed at doses of: - CORRECT ANSWER✅✅1000 rads.
Genetic effects produced by radiation in males are dependent on:
1. State of germ cell development
2. LET of the radiation
3. Interval between the exposure and conception - CORRECT ANSWER✅✅1,2,3
What is the "threshold" of radiation dose effects? - CORRECT ANSWER✅✅The dose of radiation below
which there are no effects whatsoever on the body
The three naturally-occurring radioactive decay chains are: - CORRECT ANSWER✅✅Thorium, Actinium,
Uranium
Which radionuclide is NOT a naturally occurring radionuclide? - CORRECT ANSWER✅✅Cs-137
The dose equivalent to the U.S. population from all man-made sources of
radiation is given by the NCRP as approximately - CORRECT ANSWER✅✅60 mrem/year
Most of the dose received by man from man-made sources of radiation is due to: - CORRECT
ANSWER✅✅medical applications of radiation and radioactive materials.
One Roentgen is equal to: - CORRECT ANSWER✅✅2.58 x 10-4 coulomb/kg air.
For an isotope having an allowed concentration of 1 x 10-5 µCi /cc, what is the minimum discharge time
to not exceed the concentration when 1.5 curies of activity are discharged into a stream having a flow
rate of 140,000 gallons/hour? (1 gallon = 3785.6 cc). - CORRECT ANSWER✅✅283 hours
,The energy absorbed by 1 gram of air exposed to 1 Roentgen of gamma rays is equivalent to: - CORRECT
ANSWER✅✅87 ergs.
All of the following statements about atomic structure are true EXCEPT: - CORRECT
ANSWER✅✅Electrons, protons, and neutrons are all of about equal mass
The radius of the nucleus of an atom as compared to the atom as a whole is: - CORRECT
ANSWER✅✅some 10,000 times smaller.
Isotopes are: - CORRECT ANSWER✅✅forms of the same element containing different numbers of
neutrons.
What are isotones? - CORRECT ANSWER✅✅nuclides with the same number of neutrons
Emission of a negatively charged beta particle results from the transformation of: - CORRECT
ANSWER✅✅a neutron into a proton.
Following electron capture, the following processes may occur:
1. Z increases by 1
2. Z decreases by 1
3. Characteristic x-rays are emitted
4. Auger electron emission - CORRECT ANSWER✅✅2,3,4
A technician surveys a shielded pure beta-emitting source and obtains a measurement of 0.2 R/hr. If all
beta particles are shielded, the reading is caused by: - CORRECT ANSWER✅✅Bremsstrahlung.
The dose to tissue from 6 MeV neutrons is delivered primarily by: - CORRECT ANSWER✅✅recoil
protons.
In the interaction of thermal neutrons with tissue, the major dose is from: - CORRECT ANSWER✅✅the
H-1(n,gamma)H-2 reaction
, The average energy required to produce an ion pair in air by x or gamma radiation is which of the
following? - CORRECT ANSWER✅✅33.7 eV
Which of the organ systems is the MOST radiosensitive - CORRECT ANSWER✅✅Bone marrow
Which of the following are considered risks of chronic low-level radiation exposure?
1. Sterility
2. Leukemia
3. Cataracts
4. Skin erythema - CORRECT ANSWER✅✅2
Which radionuclide is a bone seeker? - CORRECT ANSWER✅✅Ca-45
"Below a certain radiation dose, no effects whatsoever occur in the human
body." This statement supports which dose/effect theory? - CORRECT ANSWER✅✅Threshold
Why are the dose equivalent limits for occupationally exposed persons so
much higher than those set for members of the general public? - CORRECT ANSWER✅✅The number of
radiation workers is very low compared to the population, so the total risk is very small
If a linear relationship between somatic effects of radiation and absorbed dose is assumed, the number
of additional cancer deaths to be expected per million persons per rad is: - CORRECT
ANSWER✅✅greater than 100
Why is a child more radiosensitive than an adult - CORRECT ANSWER✅✅A child's cells are multiplying
more rapidly
The Systeme Internationale units Gray and Sievert represent the same
respective quantities in which of the following? - CORRECT ANSWER✅✅Rad and rem
