Well there is nothing concerning but sometime this noise you hear could be triggered by other health related issues such as blood vessels pressure, temporomandibular joint dislocation or related disorder but since you work in an environment exposes you to excessive loud noise then this should be of no concern.Try some hearing aids if the symptom is severe and have your doctor prescribe SSRIs Tricyclic antidepressant medication for a short period of time and see how that goes. Have the doctor also perform an MRI along with CT scan just to make sure things are going well.
Hope you get better soon.