A Computer Controlled System for Assessing and Classifying Noise Induced Hearing Loss

Screening audiometry is the eudiometric procedure used to assess the levels at which an individual can hear single frequency stimuli l l ).Original screening audiometry was a laborious and manual process which was highly inef cient when used as part of mass screening programs and so the automatic audiometer was developed to increase ef ciency.The result of automatic eudiometry is still an audiogram and requires the occupational health practitioner to spend much time analysing the resultant data and forces subjective judgements to be made as to whether hearing damage has occurred and whether a valid measurement has been made.The 1980's can be said to be the era when the computer made its presence felt throughout British industry and with the advent of corporate occupational health systems then the automatic audiometar's role is long due for revision.A new audicmetric device.the computer controlled audiomater will be described and its benefits for the audiometric practitioner will be highlighted. INDUSTRIAL AUDIOMETRY : THEORETICAL BASIS AND ITS USES.Hearing ability varies with frequency, and so most hearing tests are performed against a background of a controlled output and frequency spectrum.The output level varies with reference to an internationally de ned reference zero l 2 l -0 dBHL.which was derived from a test of a large group of young adults without hearing problems.IEC 645 de nes minimum test frequencies for screening audiometers, though most industrial audiometers exceed these requirements to support analysis such as categorisation.-Industrial testing assesses the lndividual's response to pure tone frequencies, whereas in clinical situations tones may be superimposed to create masking of signals or signals applied via bone conductors to access the mastoid region of the ear.These latter procedures are intended to diagnose the nature and extent of a hearing defect.which is in stark contrast with industrial audiornetry's purpose of highlighting problem casesin essence a sieving process.However, industrial screening audiometry differs from many other audiometric procedures in that