by Neil Bauman, Ph.D.
© May, 2014
A man wrote,
I am having to have a MRI scan done this week and when I went to look for ear plugs to wear under the muffs provided by the Imaging Clinic there was a pair that were a reusable gel type that had a protection rating of 27 that I liked.
I went earlier to this clinic for a previous MRI and the ear muffs I was given did me no good unless I held them tightly with my hands pressed to my ears which was emotionally traumatizing and caused my arms to cramp since the scan took over 20 minutes. Making matters worse I also have hyperacusis along with Meniere’s disease and severe hearing loss and only have a 40% word recognition level.
Since MRI’s can have noise levels in excess of 100 dB I hate to go, but need to.
The package on the 27 protection factor gel plugs had a really odd warning label on the back that concerns me and I am hoping you can address it. It said that if the plugs are pulled out too quickly that could cause permanent hearing loss.
This seems pretty hard to believe. I called the company’s 800 number, and the person I was transferred to didn’t have a clue as to why his company put that on the package.
I have no problem with slow removal—its just that if any thing were to suddenly go wrong—like a fire from the MRI machine—I might be prone to take out the plugs quickly to ask what’s going on, or simply forget after 25 minutes that it is critical to remove them slowly. The idea of using something that touchy gives me an uneasy feeling in dealing with it. I’m already thinking—OK, just how slow do I need to go!
Would the same degree of slow removal that applies to gel plugs also equally apply to foam plugs? There was a set that had a 32 protection factor rating. It’s just that in the past foam plugs have always seemed to gradually expand and work their way out. But in the MRI, it will be hard to get my hands up to adjust ear plugs back in.
Back to my question, what is this warning all about and just how slow is slow?
I’ve never seen such a warning on ear protectors, but then, I’ve only used foam ones. Here’s what I believe the warning you read is all about.
The gel plugs seal your ear canals very tightly. That’s how they prevent the sound from getting down your ear canals.
Now, if you suddenly jerk them out, what you’d be doing is momentarily expanding the volume in your ear canals just before the gel ear protectors “let go” of the sides of your ear canals and let outside air in. This creates a partial vacuum in the space between the end of the ear plug and your ear drum as you pull them out.
What happens next is that your ear drum is rapidly sucked out to some degree. Then, when the plugs “let go”, the outside air rushes in and your eardrums snap back the other way, much like releasing a stretched elastic band.
When your ear drums move (either way) they pull or push on the 3 tiny bones in your middle ears that ultimately rap on the oval windows transferring the sound to your inner ears.
Your ear drums jerking out and then snapping back violently moves these tiny bones. This excessive violent movement is similar to the movement of these bones when a rifle is shot close to your ears. This is what could result in permanent hearing loss (and tinnitus, and maybe hyperacusis)—all from this single event.
That is why you want to slowly release ear protectors so you keep your ear drum movement within normal limits.
Now to answer your question, “How slow is slow?” Good question.
Remember, “slow” is relative. Just pull them slowly enough to break the suction gradually. It shouldn’t take more than a second. Yanking them out might only take 1/100 second. That’s the difference. Slowly does not mean stretching it out over a minute, just taking a second or so.
The easy way to tell is if you begin to feel suction when you start to pull your ear plugs out, slow down. You want the suction to release slowly. If there is no suction, then any speed is fine. For example, I’ve never felt any suction with foam ear protectors so unless yours cause suction, I wouldn’t worry.
Note 1: The same applies to unvented ear molds and domes on hearing aids. Don’t suddenly yank them out, take a second to let the air pressure release slowly. On my new receiver-in-the-ear (RITE) hearing aids, if I pull them out too fast, the domes actually invert. That’s pulling too fast.
Note 2: The same also applies if you squirt water from the shower head into your ears to clean out the wax. If you have a reduced flow shower head the water comes out with little force and does not push hard on your ear drums. However, if you have a full force shower head and you let the spray hit your ear drum, it can hit it so hard that it slams it in (and again simulates a very loud sound). The result can be instant hearing loss and tinnitus.
Note 3: Even your child kissing you on your ear can cause serious ear problems from the rapid suction and releasing the suction from the kiss. You can read more about this in my article “Kiss of Deaf“.
Therefore, when it comes to your ears, don’t do anything that rapidly sucks your eardrums out or violently pushes them in. Your ears will love you for it—and you won’t risk tinnitus, hearing loss and hyperacusis from that one thoughtless moment.