Is an MRI that loud? I've had one but don't remember it being that bad.

I wear foam when using machinery and both together if shooting.

Be careful with ear muffs if you wear glasses. Not all kinds seal around the eyeglass bows, and sometimes you need to add a wedge.

I used the flange kind when I worked in a factory, but as an engineer I wasn't normally on top of a machine that long. One night I had to monitor a problem machine for a long time and very quickly discared the flange and went to the foam.