What is Deaf and Hard of Hearing?

The term Deaf usually refers to an individual with very little or no functional hearing (e.g. unable to hear anything below 70Db) and who often uses sign language to communicate. Hard of Hearing refers to an individual who has a mild-to-moderate hearing loss who may communicate through sign language, spoken language, or both. The generic term Hearing Impaired is used to describe an individual with any degree of hearing loss, which is however considered a more negative term. A large number of physical conditions (e.g., childhood illnesses, pregnancy-related illnesses, injury, heredity, age, excessive or prolonged exposure to noise) can result in varying degrees of hearing loss. The level of deafness is defined according to the quietest sound (measured in decibels) that an individual can hear:

  • Mild deafness: 25-39 decibels
  • Moderate deafness: 40-69 decibels
  • Severe deafness: 70-94 decibels
  • Profound deafness: 95+ decibels

Video explanation of deaf and hard of hearing:

  1. Oklahoma ABLETech – Assistive technology solutions for students who are deaf or hard of hearing.
  2. Rikki Poynter – What I can and can’t hear.

Examples of what people with deaf or hard of hearing experience in everyday life:

  1. David Peter – Being deaf: how different the world is without hearing.
  2. BBC – Life and deaf.



  1. U.S. Equal Employment Opportunity Commission, Questions and Answers about Deafness and Hearing Impairments in the Workplace and the Americans with Disabilities Act. Url:
  2. J.A. Albertini, Deafness and Hearing Loss, Wiley Online Library. DOI: 10.1002/9780470479216.corpsy0251.
  3. A.E. Shearer, M.S. Hildebrand, R.J.H. Smith, Hereditary Hearing Loss and Deafness Overview. In: Pagon RA, Adam MP, Ardinger HH, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2017. Url:
  4. Richang Hong, Meng Wang, Mengdi Xu, Shuicheng Yan, and Tat-Seng Chua. 2010. Dynamic captioning: video accessibility enhancement for hearing impairment. In Proceedings of the 18th ACM international conference on Multimedia (MM '10). ACM, New York, NY, USA, 421-430. DOI:
  5. J. Dammeyer, C. Lehane, M. Marschark, Use of technological aids and interpretation services among children and adults with hearing loss. International Journal of Audiology, 2017, pp.1-9.