We are leading specialists in Noise Induced Hearing Loss (NIHL).
Noise induced hearing loss (NIHL) or occupationally induced hearing loss can have a significant impact on your daily life. Usually the first symptoms noticed by many of our clients is that they complain that people around them appear to mumble. They increasingly have difficulty hearing, holding or following a conversation in the presence of background noise. This could be people talking in a work situation whereby you may have difficulty understanding instructions or interacting with colleagues, or perhaps in social situations such as being in a pub or restaurant. Usually, family and social life is the first to be affected and our clients’ have found themselves having to continually repeat themselves or having to ask others to repeat themselves, arguments with family members over ‘not listening’ or ‘shouting unnecessarily’. Ultimately, this can lead to withdrawing from social circles, embarrassment and in some occasions depression and isolation.
Noise is the term used to describe the range of sound that can range from nuisance to harmful and is usually measured in decibels (dB). High levels of sound can be harmful to the human ear and noise induced hearing loss is the damage sustained by the ear to prolonged exposure to high levels of noise. Exposure to high levels of noise must have been over a sustained period of time and for sufficient hours each day to have had a detrimental and permanent effect on one’s hearing. Hearing also naturally deteriorates with age and noise damage must be sufficiently severe to be capable of being identified in isolation to age damage, which is also known as presbycusis. It is also possible to sustain permanent damage to one’s hearing instantly and this would usually be from some form of immediate trauma, for example, being in close vicinity to an explosion or alarm; this is known as acoustic trauma.
People who suffer from noise induced hearing loss also often suffer from noise induced tinnitus, which is a ringing or repetitive sound (whooshing, screaming, thumping) in the inner ear that can be intermittent or even permanent and can be more debilitating than the actual hearing loss itself. Tinnitus is graded between slight to moderate to severe, the latter of which can be so intrusive as to wake one up from sleep or to prevent entirely concentration or even hearing. Our clients often complain of an inability to follow a TV programme or a film, read a book or even follow a recipe due to the interference of tinnitus.
What is NIHL?
E. Semicircular Canals
G. Auditory Nerve
K. Round Window
L. Oval Window
N. Ear Canal
To understand how loud noises can damage our hearing, we have to understand how we hear. Hearing depends on a series of events that change sound waves in the air into electrical signals. Our auditory nerve then carries these signals to the brain through a complex series of steps. Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum. The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear called the malleus, incus and stapes. The bones in the middle ear couple the sound vibrations from the air to fluid vibrations in the cochlea of the inner ear, which is shaped like a snail and filled with fluid. Once the vibrations cause the fluid inside the cochlea to ripple, a travelling wave forms along the basilar membrane. Hair cells – sensory cells sitting on top of the basilar membrane ride the wave and in turn the movement creates an electrical signal, which is carried to the brain, which translates into a sound that we recognize and understand. NIHL is caused by the damage and eventual death of these hair cells, which unlike bird and amphibian hair cells, human hair cells don’t grow back and are permanently damaged, hence NIHL is a permanent and irreversible condition.
Noise induced hearing loss is a cumulative condition, which means it is possible for a number of employers to have damaged your hearing by exposing you to excessive levels of noise without protection. In this scenario each employer is liable to you for a proportion and any damages you may be awarded will be divided between those employers on a proportionate basis to the length of time you were employed / exposed by each. For example 10 years of employment / exposure between 2 employers might be split on a 60/40% basis, therefore any damages you are awarded would be split between the 2 employers on the same 60/40 basis, as would the payment of your legal costs.
NIHL is ‘non progressive’, which means without further noise exposure there will be no more loss, i.e. it doesn’t get worse, it stops when your exposure to noise stops.
The date of knowledge for the industry as to noise exposure as a whole is 1963 therefore any exposure pre dating this date is not compensatable. The government published literature in 1963 advising employers as to the danger of unprotected noise exposure and therefore this date is known as the ‘date of guilty knowledge’. The literature suggested that exposure to 90dB(A) over a normal 8 hour working day was likely to be dangerous and potentially harmful. Employers should have known of the dangers to unprotected noise exposure after this date even if they did nothing to protect their employees hearing they are still liable. Prudent employers implemented hearing conservation policies and measures post 1963 and companies able to demonstrate that they did so will invariably have no liability. There are some exceptions to this rule and there is case law to support a later date of knowledge of 1972 found by the Court in a case where the defendant was a lorry company and the exposure to unprotected noise came from the lorry engine.
Some examples of typical tool noise levels are as follows;
- Jackhammer 99dB
- Shotblasting 105dB
- Caulker 98dB
- Hammer drill 102dB
- Grinder 106dB
- Stilh saw 102dB
- Press 95dB
- Guillotine 96dB
- Welding 87dB
- Kango 103dB
Typical industries and jobs where workers have likely been exposed to excessive levels of noise;
- Textiles (Weaver & Overlockers, not usually Sewing Machinists)
- Construction Industry Workers (Commercial not usually Domestic)
- Fabrication Workers
- Foundry Workers
- Steel Industry Workers
- Woodwork Industry Workers (on a large scale)
- Pre Cast Concrete Manufacture Workers
- Road Maintenance Workers
- Utilities Workers
- Car Manufacturing Industry
- Mill Workers
- Printing Press Workers
- HGV Drivers (usually only very old vehicles)
- Farmers & Farm Workers
Any claim for NIHL can encompass damages for the pain, suffering and loss of amenity, i.e. the injury or disease itself (NIHL +/or tinnitus) and for what is known as special damages and future loss, for example if it is recommended that you will benefit from hearing aids. We can claim for digital hearing aids on the private market within your claim for special damages on occasion if this is supported by the evidence.
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