Depends on your position.
The ramp agents, gate agents, and other ground pounders with ramp access are to be provided hearing protection by the company. In AA's case it was muff-type hearing protectors.
Unionized employees have a contract which may shift the burden of hearing protection onto the employee. (Only heard of this happening with the now MESA CAUSED defunct West Air)
In any case I recommend EAR or another brand with a minimum NPR of 25. Get the ones that are on a string and have a carrying case as the plugs will do engine damage if blowing around on the ramp. If your company won't provide it, you owe it to yourself to provide it.
Fly SAFE!
Jedi Nein
former ground pounder