Don't you have people coming in and out of the room at different times from breaks, people typing depending on the exam they are taking, generally moving around in their chair. These type of things.
I know at my local testing center they have huge headphones at each computer and you can ask for small earplugs or u can have both!you shoukd visit the testing center to observe this!
goodluck
When I took the DAT last year, the testing center offered headphones similar to the ones airline grounds crews wear only on a cheaper scale. They were effective at blocking out the noise but were a bit uncomfortable and distracting. I'm with 901predent. Call and ask.
they had headphones provided, but i asked them if i can bring my own earplugs, and they said that's okay too.
(I forget to take it with me on the test day tho...)
My center had headphones at every station. But there was someone who came in before me and I believed he asked if he could use earplugs and the lady said it has been banned since last year. I could be wrong but I did see him pull some earplugs out and putting it back in his bookbag. I would call the center just to make sure.