MRSO Certification Practice Exam (2026/2027) With
A+ Graded Solutions.
Section 1: Static Magnetic Fields
1. What is the unit of measurement used to describe the fringe
field of a magnet?
Correct Answer: Gauss.
2. At what Gauss level must the magnetic field be contained
within a restricted area to protect the general public?
Correct Answer: 5 Gauss.
3. What is the static magnetic field limit set by the FDA for
patients over one month old?
Correct Answer: 8 Tesla.
4. What is the static magnetic field limit for patients less than one
month old?
Correct Answer: 4 Tesla.
5. Which force is responsible for the "missile effect" on
ferromagnetic objects?
Correct Answer: Translational force.
6. What force causes a torque effect on implants as they align
with the magnetic field?
Correct Answer: Rotational force.
7. How does a ferromagnetic detection system (FDS) differ from a
standard metal detector?
Correct Answer: An FDS only detects ferromagnetic materials,
whereas metal detectors may pick up non-ferrous metals like
aluminum.
8. What is the spatial magnetic gradient?
Correct Answer: The rate of change of the magnetic field
strength over a certain distance.
, 9. Where is the spatial magnetic gradient typically the steepest?
Correct Answer: At the ends of the bore or near the portal of a
vertical field magnet.
10. What is the purpose of passive shielding?
Correct Answer: Using iron or steel plates in the walls to
reshape and contain the fringe field.
Section 2: Time-Varying Gradient Fields
11. Which law of physics describes the induction of electrical
current in the body due to changing magnetic fields?
Correct Answer: Faraday’s Law of Induction.
12. What is the primary biological effect of rapidly changing
gradient fields?
Correct Answer: Peripheral Nerve Stimulation (PNS).
13. What unit is used to measure the "slew rate" of a
gradient?
Correct Answer: Tesla per meter per second (T/m/s).
14. What is the risk of acoustic noise during an MRI scan?
Correct Answer: Acoustic injury or ruptured eardrums if
hearing protection is not used.
15. According to IEC standards, what is the maximum decibel
level permitted for acoustic noise during acquisition?
Correct Answer: 99 dBA (weighted average).
16. Where in the body is PNS most likely to be felt during a
head-first lumbar spine exam?
Correct Answer: The thighs.
17. What is the "rise time" of a gradient?
Correct Answer: The time it takes for a gradient to reach its
maximum strength, measured in milliseconds.
A+ Graded Solutions.
Section 1: Static Magnetic Fields
1. What is the unit of measurement used to describe the fringe
field of a magnet?
Correct Answer: Gauss.
2. At what Gauss level must the magnetic field be contained
within a restricted area to protect the general public?
Correct Answer: 5 Gauss.
3. What is the static magnetic field limit set by the FDA for
patients over one month old?
Correct Answer: 8 Tesla.
4. What is the static magnetic field limit for patients less than one
month old?
Correct Answer: 4 Tesla.
5. Which force is responsible for the "missile effect" on
ferromagnetic objects?
Correct Answer: Translational force.
6. What force causes a torque effect on implants as they align
with the magnetic field?
Correct Answer: Rotational force.
7. How does a ferromagnetic detection system (FDS) differ from a
standard metal detector?
Correct Answer: An FDS only detects ferromagnetic materials,
whereas metal detectors may pick up non-ferrous metals like
aluminum.
8. What is the spatial magnetic gradient?
Correct Answer: The rate of change of the magnetic field
strength over a certain distance.
, 9. Where is the spatial magnetic gradient typically the steepest?
Correct Answer: At the ends of the bore or near the portal of a
vertical field magnet.
10. What is the purpose of passive shielding?
Correct Answer: Using iron or steel plates in the walls to
reshape and contain the fringe field.
Section 2: Time-Varying Gradient Fields
11. Which law of physics describes the induction of electrical
current in the body due to changing magnetic fields?
Correct Answer: Faraday’s Law of Induction.
12. What is the primary biological effect of rapidly changing
gradient fields?
Correct Answer: Peripheral Nerve Stimulation (PNS).
13. What unit is used to measure the "slew rate" of a
gradient?
Correct Answer: Tesla per meter per second (T/m/s).
14. What is the risk of acoustic noise during an MRI scan?
Correct Answer: Acoustic injury or ruptured eardrums if
hearing protection is not used.
15. According to IEC standards, what is the maximum decibel
level permitted for acoustic noise during acquisition?
Correct Answer: 99 dBA (weighted average).
16. Where in the body is PNS most likely to be felt during a
head-first lumbar spine exam?
Correct Answer: The thighs.
17. What is the "rise time" of a gradient?
Correct Answer: The time it takes for a gradient to reach its
maximum strength, measured in milliseconds.
