No , sorry, when i was talking about saftey i was talking about the safety of your hearing. I'm fairly sure that call centres used to have their people with only one earpieced headsets, but that was damaging their hearing so now they all have to wear 2 piece headsets.
Because you will be hearing normally though the earthat is uncovered , meaning you turn up the volume alot more then you normally would to try and compensate, when compared to a hweadset that covers both ears.