I wish that hearing protection had been required or at least offered when I used to visit data centers frequently. They made a big deal of the fire suppression training, but never even suggested ear plugs. 20 year-old me had no idea how bad that noise was for my ears. I hope the staff there were wearing plugs, but it was never apparent.
I suspect I still have the record for most expletives used in front of the headmaster at my old school because someone turned a few kW speaker on while I was wiring something under the stage - i.e. I wasn't pleased.
I'm assuming telecom had very different volume-power requirements. Where I grew up there were many mid-city phone switches that were large, concrete exterior, almost windowless, buildings.
