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Magnetic Resonance Imaging (MRI)

Hi I'm Jill, Chief Safety Officer with Vivid Learning Systems. I'm a former OSHA inspector and I'm here to help you identify and correct workplace safety hazards.

For this series we're at the University of Louisville in beautiful Kentucky to show you no matter where you work safety is for everyone.

Magnetic residents, magnetic resonance imaging, or MRI as is commonly known is used in hospitals, clinics, imaging centers, zoos, aquariums, and research facilities like the one we're at today at the University of Louisville Medical School.

Now when we think about MR safety we often think about the patient. We're not always thinking about the employee, but today we're talking about employee safety considerations with magnetic resonance and with me I have Paul Harper who is a board certified MRI technologist. Thank you for being with us today. Thank you for having me.

So Paul can you explain just briefly what does a magnetic resonance imaging do? How does it work? Well what we're gonna do is put you in a very strong magnetic field use a radio wave and with those combinations we're gonna take some pictures of the inside of your body primarily soft tissues like the brains your organs and sometimes we'll do extremities.

Okay very good so what are the primary safety considerations for employees when it comes to MR safety our number-one concern when anyone enters an MRI suite is to remember the MRI magnet is always always on. We never turn it off it, never goes down nightly for an maintenance it has to stay up.

Okay very good, and so I understand that the MRI suite is where the actual magnet is but there's zones around that and there's four primary zones. Can you talk about what those zones are? The four zones are aligned for a safety aspect zone one is considered anything outside of the suite so the hallways and anything adjacent to that. Zone two would be like a patient prep area you bring a patient in they can change and lock up their belongings. Zone three is actually where we are today right here with all the equipment this is where the technologist will control the Machine and guide the patient throughout the study. And the last zone is zone four which is where the magnet as you can see behind us is house and so when you're doing your work you're primarily in zone three correct.

Okay and so what's dangerous about about MRI? Well the biggest danger is bringing anything into the environment that is ferromagnetic. To be labeled as ferromagnetic it means it has a type of magnetic property. So with our machine always being on it doesn't discriminate if it's magnetic it will pull it in. And so worst-case well maybe not worst case scenario but it let's say someone has like a scissor in there in their pocket and they go into the MR suite, what can happen? With something as small as scissors it most likely will have a ferromagnetic property what will happen is it will pull it towards the machine if it is dense enough and has enough mass behind it will stay stuck to the machine in a case like that. What we can do is go in there pull it off the machine walk most likely with two hands and then get it out of the environment.

So how do you know if a metal is ferromagnetic or not well any pure metal such as gold, silver, platinum, titanium, titanium tungsten, is non ferromagnetic a pure metal where things start becoming ferromagnetic is it becomes a combination of different metals. Okay, okay that makes sense. So someone if they had a wedding ring on would be fine. It would be fine. Yes. Okay because it's pure. Assuming that its pure. As long as we don't have to scan the anatomy around that area they can keep it on.

Okay and so what safety consideration, or I guess what kinds of employees need training and what kind of training would they need? Well anyone that would be coming into the magnet for any reason it could be a technician it could be a nurse, janitorial services, doctors, nurses anybody else that would need a reason to go into the scanner. So even like a contractor, if they were to come into the area to work on something not related to the to the magnet itself, maybe somebody needs to work on an outlet or something in the room they would need training as well. Yes. What are some of the things that you'd train employees on for those working in those zones? Well we usually put in a video information for them and go ahead classroom setting go over tutorial of the room. What can go into the room, what shouldn't go. And at the end of the day if they have any questions just ask us and we can help about. So I bet some of those primary things are the magnets always on and what ferromagnetic metals are correct. Yeah. Okay.

So you've said the magnet is always on, why is the magnet always on? Well it is filled with liquid helium. That helium is being pumped through it to cool down when I called the coils that helps get us the images. Well in order to do that it is almost at zero Kelvin, so with the liquid helium it keeps it cool. It's not something as easy to do is just flipping a switch on and off. It's a very controlled process in order to bring the machine up to operating procedure.

All right. If there's an emergency in the MR suite and the magnet has to be turned off, what happens? Great question, well we have two ways to turn off power to the machine, one way is just to kill the power and that would take all the electricity down. Now the second way is to do what's called a quench. A quench is where you release all of the helium out of the scanner when that happens it loses this magnetic field and it takes approximately about 30 seconds. After that there's no more magnetic field and you can proceed from there. So then anyone would be safe to go into the into the MR suite it's alright to respond to an emergency, wouldn't have to be making sure you are removing your ferromagnetics at that point. Correct. Okay. Very good.

What about Fire Department planning. I know that you've done some specific work with your local fire department on how to respond in the zones what were the steps that you took in what did you do with your fire department. Not every facility is manned 24/7. Some facilities may shut down for the night but once again the scanner is always on. So we got with local fire department and put together a video, so when they would have to respond facility after-hours they would know. "Hey we need to make sure that someone is either here to shut this off". You know they're a walking fire hazard MRI danger as far as we're concerned. They have on their SCBAs they'll have the hatchets you know, flashlights everything. So with that video we set it up to make sure they know what to do, who to contact at the facility and the steps they need to take to keep themselves safe also. So if a fire alarm is going off in the middle of the night and the local fire department shows up like they would they need to know how to keep themselves safe and to maintain the integrity of your of your magnet as well. Right right interesting.

Thank you Paul so much for for helping us today this is really interesting information. So remember the magnet is always on as Paul said and that it's really important to identify all the types of employees and contractors and Emergency Response personnel who may be in contact with one of the four zones so that they have the proper training to keep themselves safe.

I hope you gained a safety skill today. If you know someone who needs this go ahead and pass it on.

Safety is everyone's business.