What is a diagnostic audio?

Hearing damage from noise is fully preventable when the right precautions are taken from the start. Regular hearing tests to evaluate any early signs of hearing loss, as well as everyday preventative measures such as the use of ear plugs go a long way toward prevention of permanent hearing loss.

Companies who have employees exposed to noise level of 85dBHL are obliged to provide ear protection to their employees and to perform annual hearing screenings. Following these annual audio screenings performed by the staff at HSP Group, the company will receive a written report for employees who present with a Percentage Loss of Hearing (PLH) of 6.4% and above. According to Instruction 171 it is a legal requirement form the company to refer these employees to an Audiologist for diagnostic testing.

Diagnostic audiology is performed by a qualified Audiologist who is registered with the Health Professions Council of South Africa and with the South African Society of Occupational Health Nursing Practitioners. Testing is conducted in an annually calibrated audio booth as per SANS10182:2006.

The diagnostic testing procedure can only be performed once an employee has been noise free for at least 24 hours, this is why we conduct testing on a Monday morning after the individual has had a noise free weekend.

The testing battery includes the following:

  • A detailed case history including current job description, current noise exposure, previous employment and noise exposure history, medical history and recreational noise history. The Audiologist will request that the company provides all previous hearing tests for these employees who are tested.
  • An Otoscopic examination is performed and this includes an examination of the outer ear canal, the presence of wax and the status of the eardrum.
  • Tympanometry (variations of air pressure in the ear canal used to evaluate the condition of the middle ear eardrum]] and the conduction bones) and Acoustic reflexes testing is conducted to examine the status of the middle ear.
  • Two air conduction audiograms are conducted soundproof booth. These tests determine the threshold of hearing from 250Hz – 8Khz. Two tests are required to ensure that the results are accurate and that responses are consistent.
  • Bone conduction testing is performed to determine if the hearing loss is treatable or permanent
    • Hearing loss due to Conductive component is generally treatable
    • Hearing loss due to sensory/neural problems are generally permanent.
  • Speech reception threshold testing is also performed to ensure accuracy of air conduction testing.Instruction 171 Noise-induced Hearing Loss Reg; 2003

Findings and reporting

Following this testing, the Audiologist will determine the PLH for both audiograms and the lower valued PLH will be used to compile the report. The Audiologist will be able to determine if the loss is conductive (treatable) or sensory/neural (permanent) and if the audiological findings are consistent with a Noise-Induced Hearing Loss.

Noise-Induced Hearing Loss generally includes a symmetrical, sensory/neural hearing loss in the left and right ear and a dip in hearing from 3KHz – 6 KHz with recovery at 8 KHz.

Should the PLH be 10% and above, the Audiologist will refer the employee to an Occupational Medical Health Practitioner. Should the PLH be 30%, and above the Audiologist will refer the employee to an Ear, Nose and Throat Specialist. These medical practitioners will confirm if the hearing loss is due to noise exposure and will complete all relevant documentation for COID, RMA or FEM for compensation.

The Audiologist will also provide counselling to the employee on the importance of noise protectors, the impact of hearing on social interaction and ways to minimize any further hearing loss. The Audiologist will also provide any recommendations to the company should the employee require specialised ear protection or should the employee not be safe working in a specific zone if the hearing loss is severe.

The Audiologist encourages all employers and employees to be mindful that we all need to protect and conserve one of our most valuable possessions: the sense of hearing.

To book your consultation with our audiologist, contact us on 011 391 7113 or email sunnyridge@hspgroup.co.za

Written by Carey Ann Morris