Category Archives: Audiometric Testing

The Process of Audiometric Testing in The Workplace  

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Audiometric testing in the workplace is not new, however, in recent times, due to the inclusion of regulations in the OHSA act, the practice has become more prevalent. After 2005 when noise regulations were imposed stating that anyone who is subjected to noise levels of 85 dB or more must be provided with audiometric testing to safeguard the employer and employee in the event of future necessity. The concept of audiometric testing in the workplace is very much like an audiometric test you would more than likely have undergone at school to measure your hearing abilities. This kind of testing in the workplace situation is carried out either in specially designed mobile units or a quiet room within the building, whichever is more suited to the requirements and preferences of the company involved.

The Process Itself is Painless

The audiometric testing process is fairly simple and completely painless. The person being tested is asked to wear a set of headphones. A series of sounds of differing volumes and pitches are transmitted through the headphones. The person being tested acknowledges when a sound is heard and in this way the tester is able to identify whether or not any hearing loss has taken place. Each test only takes about fifteen minutes to complete and the use of highly calibrated equipment is essential for valid results. Each test will be presented with results allowing the company to take the necessary precautions and measures to comply with noise regulations and ensure the safety and health of their employees.

Testing Protocol

Any audiometric testing in the workplace should always be carried out by a professional who is certified and has the necessary experience in the field. Equipment used needs to be of the highest caliber and compliant with all health and safety regulations set in place by the state. The initial testing should take place within the first three months of employment and the results from that should be used as the baseline against which all other future results are to be measured. The follow up test needs to be undertaken after twelve to twenty four months at the maximum to measure whether any hearing loss has taken place or if hearing has remained constant. Follow up monitoring bi-yearly, or more frequently in high risk situations, is required if no shift in threshold has been measured.

What Are Threshold Shifts?

When your hearing is exposed to noises above 75 dB, the sensitivity of your ears will decrease. This process of de-sensitising is called a threshold shift and can take place in a number of ways.

  • Temporary threshold shift recovers gradually after noise exposure.
  • Permanent threshold shift does not recover and is permanent.

Precautionary Measures and Actions

There are actions that need to be taken in instances where sufficient hearing loss has taken place to compromise the safe performance of employees and interfere with their communication abilities.

  • All avenues should be investigated and practicable steps taken to modify the work environment.
  • Offering employees alternative work which does not subject them to excessive noise that could further damage their hearing.

From the moment any shift in threshold is noted, permanent or temporary as well as tinnitus, the employer needs to be notified so that the following actions can be taken:

  • Re-determine the employees’ noise exposure
  • Take remedial action to reduce the level of noise exposure as well as the duration if possible
  • Ensure that the hearing protection used by the employee is adequate for the level of noise exposure
  • Review the employees’ job and identify any possible changes that could have increased levels of noise exposure the employee is subjected to which may have caused an increase in hearing loss
  • Check the fit of the hearing protection worn by the employee
  • Identify whether or not the employee has any difficulties using the hearing protection
  • Check if the hearing protection is being used correctly

 

Employee Awareness

Empconstruction-worker-956495_1920loyees are not safety professionals and are not aware of the risks posed by exposure to loud noise but they do need to be made aware. An employer who is safety conscious will do whatever is in their power to motivate and educate their employees on the risks involved and preventive measures that can be undertaken. Just as it is the job of the employer to ensure a safe environment for the employees, one that protects their hearing, it is also the responsibility of the employee to do what they can to protect their own hearing.

Eradicate The Illusion That The Employee is Invincible

 As with many young people starting out whether in life or industry, they have this perception that they are invincible and that nothing can harm them. There are many workers young and old who do not believe that they are susceptible to any hearing loss risk in the workplace. Yes, over time your brain adjusts and becomes accustomed to the levels of noise around you and you may find many people making statements like they are used to the noise or it isn’t that loud when all indications and measurements show something vastly different. Your ears don’t get used to the noise, any reduction in the noise is caused through hearing loss. The employee needs to make the employee realise they are at risk and they are not invincible by producing facts. Each employee must undergo audiometric testing and the results must be kept as valid proof. Any progression of hearing loss by a scientific test such as this is enough to shake anybody into action. It has been shown that noise induced hearing loss numbers are reduced after annual audiometric testing report reveals hearing loss. In some cases the hearing loss is so unnoticeable during everyday life, however, it is enough to affect the hearing measurement. Companies can be proactive in publicly broadcasting noise level in areas or for particular equipment and this has shown a marked improvement in the number of employers who make use of their hearing protection. By posting the noise measurements publicly it also allows temporary worker and visitors to be warned of the dangers as well as reminding permanent staff. Educating workers about noise and the damage it can cause is the best way to ensure any controls you put in place are effectively enforced and implemented.

Demonstrate and Discuss Future Risk

As is human nature, employers are more concerned with the risks that will affect them now. Noise-induced hearing loss is not immediately noticeable and it occurs over time. The employer needs to make them aware of the future risks involved. Employers often use simulated hearing losses or audio demonstrations to convey the message to employees of what could happen if they aren’t religious about their hearing protection. In instances where noise damages the hearing, the noticeable difference is experienced in clarity rather than how loud it is. This can be due to fact that noise induced hearing affects sounds that have a frequency.

Remove The Obstacles and Barriers to Wearing Hearing Protection

As an employer, don’t allow your staff to make excuses for not wearing protective gear. Ask the question after the regular audiometric testing and you may be surprised by some of the answers provided. Ensure that hearing protection is always readily available or provided in dispensers. Always ensure that the hearing protection selected is suitable for the application. Many employees choose against wearing the gear because it causes obstacles in communication, job performance or is simply just uncomfortable to wear. Selecting hearing protection with this in mind will eliminate any potential barriers to hearing safety procedures.

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In conclusion

At the end of the day it is both the responsibility of the employer and employee to protect the hearing of the employees. The employer can make every opportunity available, however, if the employee fails to see the importance then all good done by the employer is eradicated. Because noise induced hearing presents no pain or visible trauma and the results are progressive, it is often not noticeable in the early stages and in the mind of the employee doesn’t exist. This is why it is so urgent that employees are made aware of the future risks involved.

Audiometric testing is not an option, it is a necessity that should be included in any employment contract. Safeguarding the employer as well as the employee in every instance. Regular testing and results is the only way to keep a handle on the situation and identify possible problems in the workplace that need to be attended to in order to prevent further damage to the affected or other individuals.

It is the employers’ duty to be rigid in their application of rules and regulations pertaining to hearing loss protection but also to educate the workforce as to why the need for it is so vital. It isn’t always easy to make employees understand what future risks could be when they aren’t affected by it now. This is where innovation and creative thinking plays a role. Use videos, posters, audio displays and whatever else you may find useful to relay the message. Perhaps get workers who have been affected by noise induced hearing loss to talk at safety meetings and help the employees to understand what the difficulties are that they have experienced and the implications of not making use of protective measures.

The implications of hearing loss in the workplace are far reaching and don’t only affect your ability to communicate at work but at home and in public as well. Safety concerns are raised in all areas where hearing loss has occurred. You are not only put at risk in the workplace but in any daily activity you undertake. Something as simple as crossing a street can be detrimental. Quality of relationships deteriorates due to lack of communication or miscommunication.

If you know you have been subjected to extended periods of loud noise in the workplace and you feel your hearing may be compromised, or even if it appears fine to you, go for audiometric testing. The results are well worth the fifteen minutes spent during the appointment. If all is clear then your mind is at ease, however, if not you may have caught it early on and you can still take measures to prevent further loss. In cases where hearing loss is already severe, you will be able to obtain advice on what aids and options are available to you.

The professional carrying out the audiometric testing will be able to properly explain to you the damage caused and the extent of that damage. They will be able to provide you with the necessary information regarding your type of hearing loss and make you aware of the risks going forward. As with anything in life, knowledge is power.

If you happen to be an employer, take the necessary steps to protect your employees from suffering noise induced hearing loss due to the environment in which they work. Your employees will thank you for it. A workforce that is well-looked after, happy and healthy is one that will reward you with productivity. In business your workforce is your set of tools and as with any tools if not properly oiled and maintained and left to degenerate, they won’t perform and are more likely to just stop working completely. For a business that flourishes, the workforce must be healthy and content and audiometric testing and hearing protection is just a step in the right direction.

Don’t risk the rest of your life because you think you are invincible and above the risks posed in the workplace. You many not recognize the symptoms of your negligence now, however, you will be affected over a period of time and when you do realise it, your hearing loss may already be significant and pose risks to your well being. Make your booking for your audiometric testing or speak to your employer now to work safely and maintain good health.

Noise Reduction in Workplace

Noise reduction1

Work-related noise-induced hearing loss is a preventable but irreversible condition that affects many Australian workers.
 Between 28–32% of the Australian workforce is likely to work in an environment where they are exposed to loud noise at work.

 Noise-related injuries are most common in the manufacturing and construction industries with technicians and trades workers, machinery operators, drivers and labourers most exposed.
Too much noise at work can lead to temporary or permanent hearing loss or tinnitus (ringing in the ears). Hearing damage can occur from extended exposure to noise or exposure to very loud impact or explosive sounds.
 Long term exposure to loud noise is the most common preventable cause of hearing loss.

According to WHS Regulations, the exposure standard for noise involves two measures:
 LAeq,8h of 85 dB(A)
 LC, peak of 140 dB(C).

LAeq,8h of 85 dB(A) implies that over an eight-hour shift a worker cannot be exposed to more than 85 decibels. Whether this is exceeded depends on the level of noise involved and how long a worker is exposed to it.
LC, peak of 140 dB(C) means a worker cannot be exposed to a noise level above 140 decibels. Peak noise levels greater than this usually occur with impact or explosive noise for instance, a gun-short or a sledge-hammering. Any exposure above this peak can create almost instant damage to hearing.

 These limits should protect most but not all people. The risks from workplace noise must be eliminated or minimised so far as is reasonably practicable.
Ideally, you should keep noise levels below:
 50 decibels if your work requires high concentration or effortless conversation
 70 decibels if your work is routine, fast-paced and demands attentiveness or if it is important to carry on conversations.
Managing risks
If you have a noisy workplace with any noisy activities that may expose workers to hazardous noise levels, you should assess the risks by carrying out a noise assessment.
A noise assessment will help you:
 identify which workers are at risk of hearing loss
 determine what noise sources and processes are causing that risk
 identify if and what kind of noise control measures could be implemented
 check the effectiveness of existing control measures.

Complex situations may need measurement to determine a worker’s exposure to noise, such as workplaces with variable noise levels over a shift and jobs where workers move in and out of noisy areas. A noise assessment should be done by a qualified Health and Safety Professional in accordance with the procedures in AS/NZS 1269.1.

Steps to control noise in a workplace

The WHS Regulations require PCBUs to work through a hierarchy of control to choose the measure that eliminates or most effectively minimises the risks in the given situations.

 The most effective control measure is to eliminate the source of noise completely.

 If you cannot eliminate the noise, look at reducing it.
Remember that actions to eliminate or minimise noise may introduce new hazards, and risks associated with those hazards need to be managed effectively.
Other ways to minimise noise include:
 Engineering controls: These are common control measures and involve modifying equipment to reduce noise at the source or alternatively place barriers of plywood around the noise source. Barriers can also be placed along the transmission path to minimise noise levels or they can be placed around the worker to prevent noise exposure.

 Administrative controls: These involve using noisy machines during shifts where lesser people are exposed, limiting the amount of time a person spends near a noise source, moving workers away from the noise source to reduce their exposure or providing quiet areas where workers can be relieved from hazardous noise sources.

 PPE: Personal hearing protectors such as ear-muffs or ear-plugs should be used: when the risks arising from exposure to noise can’t be eliminated or minimised by other more effective control measures

o as an interim measure until other control measures are implemented
o where extra protection is needed above what has been achieved using other noise control measures.
The risk of occupational noise-induced hearing loss is increased by relying too much on, and improperly using, personal hearing protectors such as ear muffs and plugs.
Audiometric testing
According to WHS Regulations, a PCBU must provide audiometric testing for a worker who is carrying out work if they are required to regularly use personal hearing protectors as a control measure for noise that exceeds the exposure standard.
 Audiometric testing must be provided within three months of a worker starting work that exposes them to a risk of work related noise-induced hearing loss.
Starting the audiometric testing before people are exposed to hazardous noise (such as new starters or those changing jobs) provides a baseline as a reference for future audiometric test results.
Regular follow-up tests must be carried out at least every two years. These should be carried out well into the work shift so that any temporary hearing loss can be identified.
How Can We Help?
Anitech Noise Solutions can help you by assessing the noise level in your workplace and we also provide tailored advice on complying with the laws in your state. Our consultants are certified OHS professionals who can help with audiometric assessment or hearing tests of the exposed workers. Anitech Noise Solutions offers simple, affordable noise compliance solutions based on your requirements.

Contact us on 1300 889 289 to have more information about noise assessment and audiometric assessment.

For more information, see Safe Work Australia Publication: https://www.safeworkaustralia.gov.au/noise

 

Audiometric Testing: Did You Hear That?

Depending on your local health and safety regulatory jurisdiction, audiometric testing will be required once decibels reach a specific action level.  Audiometric testing is part of an organizations overall hearing conservation program that is completed annually, at a minimum.

What is an audiometric test? It is a test to determine a workers’ hearing levels with the help of an audiometer.  Simply put, it is a test to determine how well you can hear, or not hear?  The test will validate if a workers’ hearing is being compromised or not.

Audiometric Testing

Audiometric testing identifies…

–  Progressive noise-induced hearing losses before they become an impairment

–  Temporary losses before they become permanent, providing time for remedial steps

The audiogram is a graphical display of the hearing test. The audiogram (a graph or table of an audiometric test results) will be available to the worker and by the employer.

The two main components that are graphed are frequency and intensity. These results are displayed for each ear. When you had your hearing tested, the audiologist was determining the softest sound you could hear at each specific frequency.  Without regular audiometric testing you may not know your hearing is being compromised until it is too late!

Below are the 4 steps needed to ensure that noise, as an occupational hazard, is monitored and operational controls are in place to minimize or eliminate such noise.

  1. Measure your workplace sound levels to determine who needs to be tested.
  2. Review engineering, administrative and personal protective measures to limit worker noise exposure.
  3. Schedule mobile testing, and provide training for employees affected by noise.
  4. Understand local jurisdictional and other regulatory bodies requirements for noise hazards and maintain compliance.

PRE TEST EXAMINATION

The examiner will ask you questions as part of the evaluation…

–  Ear, nose, & throat problems such as colds, infections, and congestion?

–  Noisy hobbies or activities?

–  Time since exposure to loud noise?

The examiner may also visually check your outer ear canal with an otoscope for…

–   Ear infections

–   Excessive earwax

–   Obstructions in the ear canal

AUDIOMETRIC TEST

  • You will sit in a quiet booth and be equipped with a headset and a signal switch
  • You will hear tones of varying level and frequency
  • You will be instructed to depress the signal switch to indicate a tone was heard
  • Be honest; don’t try to anticipate or intentionally miss a tone, or the test will be invalid

AUDIOMETRIC TEST RESULTS

Your audiogram will be used to indicate hearing change.

–    A Temporary Threshold Shift (TTS)

  • A temporary reduction in hearing due to fatigue of the ear caused by noise exposure
  • Temporary hearing loss – indicates the potential for permanent loss

–    A Standard Threshold Shift (STS)

  • A change in hearing sensitivity for the worse relative to the baseline audiogram
  • An average change of 10 dB or more at 2, 3, and 4 kHz in either ear

The benefits of participating in an audiometric test include preventing adverse effects such as tinnitus – ringing in the ears; temporary hearing loss or permanent hearing loss.   Noise is an occupational hazard that can be identified, controlled and measured.  Audiometric testing is a validation of how effective an employer’s hearing conservation program is, or is not.

 

Audiometric Testing: The Various Types of Tests

There are multiple types of audiometric testing to validate if a workers’ hearing health has been jeopardized due to working around noise.  Some of these tests are briefly described in this article.

Audiometric Testing

  1. Pure Tone Audiometry

Pure tone audiometry (PTA) tests are the most common type of test used for evaluation of occupational noise.  During PTA, a machine called an audiometer is used to produce sounds at various volumes and frequencies (pitches). You listen to the sounds through headphones and respond when you hear them by pressing a button.

  1. Speech Perception

The speech perception test, also sometimes known as a speech discrimination test or speech audiometry, involves testing your ability to hear words without using any visual information. The words may be played through headphones or a speaker, or spoken by the tester.  Sometimes, you are asked to listen to words while there is a controlled level of background noise.

  1. Tympanometry

During tympanometry, a small plastic bung seals your ear and the machine gently changes the pressure in your ear canal. The purpose of a Tympanometry test is that it measures the movement of the eardrum and the pressure behind the eardrum to determine if any fluid is behind the eardrum.  It will also indicate if the Eustachian tube is working properly or not normally.

  1. Whispered voice test

The whispered voice test is a very simple hearing test. It involves the tester blocking one of your ears and testing your hearing by whispering words at varying volumes. You will be asked to repeat the words out loud as you hear them.

  1. Tuning fork test

A tuning fork test produces sound waves at a fixed pitch when it is gently tapped and can be used to test different aspects of your hearing.  The tester will tap the tuning fork on their elbow or knee to make it vibrate before holding it at various different locations around your head.

The purpose of the tuning fork test is to help determine if you have conductive hearing loss, or sensori-neural hearing loss.

  1. Bone conduction test

A bone conduction test is often carried out as part of a routine pure tone audiometry (PTA) test in adults.  A bone conduction test involves placing a vibrating probe against the mastoid bone behind the ear. It tests how well sounds transmitted through the bone are heard.  The bone conduction test is a far more sophisticated version of the tuning fork test, and when used together with PTA, it can help determine whether hearing loss comes from the outer and middle ear, the inner ear, or both.

  1. Hearing Test Results – The Audiogram

The results of some hearing tests are plotted on a graph called an audiogram.  An audiogram is used to record the measurements of different volumes and frequencies (pitches) of sounds you are able to hear.  As well as showing a comparison between your ears, an audiogram can also help to determine what type of hearing loss you have, if any.  The type of hearing loss you have is important because it determines what help or treatment is most suitable for you.

Audiometric Testing: The Audiogram

If you have experienced an audiometric test, chances are you have seen and been told the results of your test via a graph.    But did you really understand the information?  Was the information not communicated well to you?  This article will provide, in general terms, an explanation of what an audiogram represents.

The audiogram is a chart of hearing sensitivity with frequency charted on the X- axis and intensity on the Y-axis. Intensity is the level of sound power measured in decibels; loudness is the perceptual correlate of intensity.  Below is an example of an audiogram:

Audiometric Testing

Most common way to measure hearing sensitivity is to measure pure-tone (sinusoid) thresholds.

Below is an example of an audiogram.  The red line is the right ear of this particular worker.  This audiogram represents Pure Tone Average (PTA).  The average thresholds at 500, 1000, 2000 Hz are the frequencies most important for speech understanding .  In this particular scenario, the PTA of the left ear was 93 dB compared to 50 dB of the right ear.

Audiometric Testing

The magnitude of hearing loss is defined as follows:

  • Normal hearing loss:  0 -15 dB.  Some interpretations have normal hearing loss ranging up to 25 dB
  • Slight hearing loss:  16-25 dB
  • Mild hearing loss:  26-40 dB
  • Moderate hearing loss:  41-55 dB
  • Moderately-Severe hearing loss:  56-70 dB
  • Severe hearing loss:  71-90 dB
  • Profound hearing loss:  91+dB

There are 3 types of Hearing Loss to understand when reviewing your audiogram:

  1. Conductive is abnormality of the outer or middle ear.  Usually temporary and medically treatable.The Impaired Ear (Conductive Loss) occurs when there is a disruption of the transmission of sound (Ex: fluid in the middle ear).  Typically, this loss occurs in the outer or middle ear and many times is a temporary loss that can be treated medically.
  2. Sensorineural is damage to the inner ear or nerves of hearing.  Usually permanent. The Impaired Ear (Sensorineural Loss) occurs for many reasons.  Starting from age 20, the hair cells slowly begin to deteriorate.  Hair cells can also be damaged from loud noises, medicine, head trauma or other causes.  This type of hearing loss are mostly due to natural loss of hair cells.
  3. Mixed include both Conductive and Sensorineural.

 

Besides just understanding the audiogram, it is important to remember that audiometry is a subjective test requiring a verbal or physical response and therefore can be subjective.  Audiometry tests all parts of the ear, the entire auditory system.  The most common type of audiometry, that you and I are familiar with is the Pure Tone audiometry test.  This type of test includes headphone, insert earphone or speaker.  A machine called an audiometer is used to produce sounds at various volumes and frequencies (pitches).You listen to the sounds through headphones and respond when you hear them by pressing a button.This test evaluates the sensitivity of the entire hearing organ.  The audiologist presents single frequency (“pure”) tones produced by a calibrated audiometer. The softest sounds heard by the subject at each pitch are recorded as the thresholds and are compared to normative values.  This recorded comparison is found on the audiogram, a graph that you now understand what it means and how it benefits you by knowing what type, if any hearing loss you may have.  The type of hearing loss you have is important because it determines what help or treatment is most suitable for you.