MRSO PRACTICE EXAM QUESTIONS AND ANSWERS
physical effects of STATIC FIELDS - Answer translation
rotation
lenz
physical effects of TIME-VARYING FIELDS - Answer motion
noise
induced currents (on object/in person)
lenz
translation
rotation
everything NOT MR SAFE needs to be behind... - Answer 5 gauss line
earth's magnetic fiels - Answer 0.5 gauss
1.5T = ___ gauss - Answer 15,000
3 T = ___ gauss - Answer 30,000
MR device can be considered non-significant risk IF: (list) - Answer static mag
field
SAR
dB/dt
sound pressure level
^ are below certain threshold
dB/dt - Answer gradient fields rate of change
can produce severe discomfort/nerve stimulation
limits for# Tesla adults can take - Answer 8T
limits for # Tesla a >1month old can take - Answer 4T
max unprotected sound level - Answer 140 dB
, max PROTECTED sound level - Answer 99 dBA
biological effects of strong mag fields - Answer vertigo
dizziness
nausea
magnetohydrodynamic effects
induced electric currents... (for time-varying....)
magnetophosphenes
nerve stimulation/tingling
hair static (electric charges on skin)
are there known fetal effects of strong magnetic fields? - Answer nope
magnetohydrodynamic effect - Answer bloodflow changes because blood is
flowing inside a strong magnetic field; b/c of ions veering left or right
occupational threshold for sound pressure level - Answer for 8hr shift: 90dB
Engineering controls - Answer eliminate/reduce exposure to hazard through use
of engineered structures/machinery/equipment
badge access, 4-zone design, shielding around magnet
Administrative controls - Answer eliminate/reduce hazard by
modifying/implementing administrative practices
visual signs, zone notices, ferrous-free sweeps, MRSO on each shift, floor
markings
PPE - Answer ex. hearing protection (headsets, earplugs)
MAX TORQUE in a scanner is __ - Answer at scanner ISOCENTER
MAX TRANSLATIONAL FORCE in a scanner is __ - Answer at scanner BORE
ENTRANCE
how to read static magnetic field map - Answer move further from bore -->
magnetostatic lines are spaced further out
higher static magnetic field --> can experience __(more/less)___ torque - Answer
MORE
physical effects of STATIC FIELDS - Answer translation
rotation
lenz
physical effects of TIME-VARYING FIELDS - Answer motion
noise
induced currents (on object/in person)
lenz
translation
rotation
everything NOT MR SAFE needs to be behind... - Answer 5 gauss line
earth's magnetic fiels - Answer 0.5 gauss
1.5T = ___ gauss - Answer 15,000
3 T = ___ gauss - Answer 30,000
MR device can be considered non-significant risk IF: (list) - Answer static mag
field
SAR
dB/dt
sound pressure level
^ are below certain threshold
dB/dt - Answer gradient fields rate of change
can produce severe discomfort/nerve stimulation
limits for# Tesla adults can take - Answer 8T
limits for # Tesla a >1month old can take - Answer 4T
max unprotected sound level - Answer 140 dB
, max PROTECTED sound level - Answer 99 dBA
biological effects of strong mag fields - Answer vertigo
dizziness
nausea
magnetohydrodynamic effects
induced electric currents... (for time-varying....)
magnetophosphenes
nerve stimulation/tingling
hair static (electric charges on skin)
are there known fetal effects of strong magnetic fields? - Answer nope
magnetohydrodynamic effect - Answer bloodflow changes because blood is
flowing inside a strong magnetic field; b/c of ions veering left or right
occupational threshold for sound pressure level - Answer for 8hr shift: 90dB
Engineering controls - Answer eliminate/reduce exposure to hazard through use
of engineered structures/machinery/equipment
badge access, 4-zone design, shielding around magnet
Administrative controls - Answer eliminate/reduce hazard by
modifying/implementing administrative practices
visual signs, zone notices, ferrous-free sweeps, MRSO on each shift, floor
markings
PPE - Answer ex. hearing protection (headsets, earplugs)
MAX TORQUE in a scanner is __ - Answer at scanner ISOCENTER
MAX TRANSLATIONAL FORCE in a scanner is __ - Answer at scanner BORE
ENTRANCE
how to read static magnetic field map - Answer move further from bore -->
magnetostatic lines are spaced further out
higher static magnetic field --> can experience __(more/less)___ torque - Answer
MORE
