fmrilevel1

Question 1

what is the 5 gauss magnetic field line?

Answer 1

safety boundary

when you enter magnet room, you’re in an area with a magnetic field of 5 Gauss or greater

bounded by magnet room

Question 2

What does it mean to be in an area w/ magnetic fields of 5G or greater?

Answer 2

implants/inclusions will be affected

metallic objects electronic devices in body might malfunction or twist, leading to death or injury

outside body, will become projectiles and potentially cause sever injury/death

Question 3

items not allowed in scanning room

Answer 3

belt, coins, necklaces, piercings, rings, watch, pens, keys, credit cards (!), eyeglasses, cell phone, any electronic device, belly button rights, vena cava umbrella, back brace, etc

transport trolleys, traction devices, gas tanks, etc

any thing magnetizable

check w/ meta detector wand and walk-through metal detector to be sure there are no metal objects

Question 4

medical conditions disqualifying from entering magnet room

Answer 4

injury for metallic object or foreign body or from metal work, pregnancy, aneuryism clip, cardiac pacemaker, eletronic implant/device; cochlear, otologics, or other ear implant; spinal cord stimulator; any type of prosthesis, heart valve prosthesis, artificial or prosthetic limb, metallic stint, joint replacement (hip, knee)

Question 5

when is the magnetic field off?

Answer 5

it is always on

Question 6

who is responsible for people allowed in scanning area?

Answer 6

me

Question 7

liquid helium

Answer 7

used daily as coolant for magnet; could displace oxygen in room if escaped

Question 8

situations in which helium could escape

Answer 8

magnet quench, broken pipe

Question 9

in the even tof helium release

Answer 9

evacuate scanner room immediately and activate emergency exhaust button to ventilate the helium from teh scanner room

Question 10

oxygen monitor levels

Answer 10

If below 18%, warning lights. 14% sound alarm. 11% breathing is difficult.

Question 11

15-19.5% oxygen

Answer 11

decreased ability to work strenuously, impaired coordination, induced symptoms in thise w/ coronary or pulmonary or circulatory problems

Question 12

12-15% oxygen

Answer 12

respirationd eepns, increased pulse rate, impaired coordination, perception, judgment

Question 13

10-12% oxygen

Answer 13

Further increase in rate and depth of respiration, further increase in pulse rate,
performance failure, giddiness, poor judgment and blue lips.

Question 14

8-10% oxygen

Answer 14

Mental failure, nausea, vomiting, fainting, unconsciousness, ashen face, blue lips.

Question 15

5-8%

Answer 15

8 minutes may be fatal in 50-100% of exposures; 6 minutes may be fatal in 25-50%
of exposures; 4-5 minutes, recovery with treatment.

Question 16

4-6%

Answer 16

Coma in 40 seconds, convulsions, respiration ceases, death.

Question 17

oxygen monitor location

Answer 17

in console room near door

Question 18

emergency power shutdown button

Answer 18

turns off all MR hardware including host computer. Does not turn off magnetic field.

Question 19

emergency power shutdown button locations

Answer 19

1) right of viewing window in skyra control suite (left of quench button)
2) left of door as you walk into machine room
3) right on wall as you walk into skyra magnet room

Question 20

magnet quench

Answer 20

only use if an emergnecy siutation for persons in magnetic field exists.

Examples: magnet attracted large piece of metal, person caught between it and magnet, and 1 person can’t remove it easily; a thin piece of metal has been attracted by magnet and caused serious injury

Not when no one is in danger. Instead start by contacting someone on emergency list, emailing mrihelp@princeton.edu etc. Siemens if no one answers.

Question 21

what happens when magnet quenched

Answer 21

Liquid helium, used to cool the magnet, is vaporized and reeased via exhaust line. Rise in temperature in magnet causes coils to lose superconductivity and field strength rapidly falls.

helium is released, displacing oxygen is scanner room. This causes oxygen content in room to drop really low, and death by asphyxiation can occur. Helium droplets may form on exhaust vent lines that coudl cause frostbite if touched.

serious damage may result to magnet, making further use impossible until a technician comes to return it to service.

Question 22

locations of magnet quench

Answer 22

in console room to right of monitors, and in magnet room to right of door when you walk in.

Each protected by plastic door and yellow sticker to prevent acccident.

Question 23

emergency exhaust button

Answer 23

immediately after magnet is quenched or pipe has broken, allowing helium to be lrelaesed and increase oxygen flow.

Located to right of oxygen monitor in skyra room

Question 24

procedure for non-medical emergency

Answer 24

abort scan, emergency shutdown button, help subject out and evacuatte scanner area, call public safety (609-258-1000) and specify location of emergency, contact someone on emergency contact list

Question 25

magnet safe fire extinguisher location

Answer 25

outside bathroom in between two magnet rooms

Question 26

how to automatically initiate a quench

Answer 26

when helium leel has dropped below 20% or when there’s a sudden power loss to the MRI scanner