• Specialty
  • Cardiology
  • Dentistry
  • Dermatology
  • General Medicine
  • GI/GU
  • Hematology
  • Immunology
  • Lab Medicine & Pathology
  • Neuro-Psych
  • OB-Gyn
  • Oncology
  • Ophthalmology
  • Orthopaedic
  • Otolaryngology - ENT
  • Radiology
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• Otolaryngology - ENT
  • Common ENT Terms
  • Ear Related Terms
  • Nose Related Terms
  • Rhinoplasty Terms
  • Throat Conditions
  • Sample Reports - Otolaryngology - ENT

• Ear Related Terms

- N -

• Neurofibromatosis-2

Genetic disorder often leading to tumors on nerves.



• NIHL

Noise Induced Hearing Loss due to noise exposure.



• Noise

Generally defined as unwanted sound.



• Noise-Induced Hearing Loss (NIHL)

Irreversible hearing loss caused by exposure to very loud impulse sounds, such as an explosion, or to less-intense sounds for an extended period of time. Loud noise levels damage hair cells of the inner ear.



• NRR/Noise Reduction Rating

NRR, or Noise Reduction Rating is a rating system set up by the Environmental Protection Agency (EPA) as a guideline that indicates the amount of potential protection a hearing protection device will give in a noisy environment. All Howard Leight hearing protection devices are tested under the Real Ear Method as directed by the American National Standard Institute (ANSI) in accordance with test procedures established by the Acoustical Society of America. All testing is performed in a controlled environment. Consequently, posted NRR ratings are a qualified example of how the individual products compare with other similar hearing protection products in an uncontrolled noise environment. Test results do not evaluate the product reusability, comfort, adaptability or quality. In the final analysis, the user must make this determination.