Which PPE best prevents workplace hearing loss?

Noise-induced hearing loss (NIHL) has an alarmingly high incidence, particularly in the industrial sector. This type of injury is often the basis for workers compensation claims and can cost companies billions of dollars in damages.

Background analysis of noise exposure data submitted to the Safety Regulation System (SRS) shows that a large percentage of industrial workers are regularly exposed to noise levels that could cause permanent and debilitating damage.

Therefore, finding the right PPE to prevent workers from experiencing hearing damage is crucial.

Why are heavy industry workers at higher risk?

High noise levels and proximity to loud machines and heavy-duty equipment, such as grinders and industrial machines, have a negative effect on hearing. Noise levels can exceed 105 dB around this equipment.

The measurement used to quantify noise exposure is the LAeq8h, which is indicative of the total amount of noise energy that the ear absorbs over an eight-hour period. Based on recent exposure monitoring data, areas of significant concern include:

• 61% of all noise exposure measurements for workers exceeded 85 dBA.
• In more than 35% of the noise exposures exceeding 85 dBA, the worker was not using PPE.
   

Failure to use hearing protection is consistent across all ages and occupations, including workers in management and supervisory roles.

Hearing loss and permanent damage

The severe or repeated stress associated with noise exposure (including occupational) causes permanent damage to neural tissue in the inner ear, leading to hearing loss. Hearing loss can impair communication and is associated with an acceleration of cognitive aging and increased risk of dementia, as well as increased heart rate and blood pressure, headaches and problems to concentrate. As neural tissue cannot regrow once it is lost, there is limited scope for recovery once the consequences of noise exposure become detectable.

Individuals who have experienced hearing loss need to be protected from further damage. Possible symptoms include difficulty hearing warning signals, difficulty in communicating, accidents caused by problems with hearing and a ringing or buzzing in the ears. After an employee leaves a noisy area, their hearing may seem dull or muffled.

Hearing loss usually occurs gradually, so people may not realise it until it’s too late. But hearing loss is 100% preventable. Unfortunately, once it occurs, the damage can’t be reversed and there is no cure.

Hearing protection and the legal workplace obligations

By law, hearing protection is required in any workplace environment where the average noise levels exceed 85 dB. From April 2018, health and safety personnel must also make sure that the hearing protection products used by employees comply with the Australian Personal Protective Equipment (PPE) Regulations as outlined by Safe Work Australia.

It is critical for industrial workers and their management to be aware of workplace noise exposures. Control of noise emissions at source and avoidance of exposure are critical to hearing conservation. Hearing protection becomes necessary if noise does exceed the safe threshold.

Hearing protection can only be effective if it is consistently and correctly worn by workers — and if it fits well.

Earmuffs are commonplace, but have disadvantages

Earmuffs offer a little protection, but make sound muffled and communication very difficult. Industrial workers often complain of confusion about identifying spoken words and reduced audibility when wearing conventional hearing protectors. A lack of clear communication frequently leads to an increased risk of workers struck by moving equipment or errors made due to poor communication with co-workers.

Over-attenuation can also endanger the user, as warning sounds are blocked. In noisy environments, workers are often forced to move to a quiet area, or they may rely on the use of hand signals to communicate.

Although very common, earmuffs can also be uncomfortable to wear — particularly in combination with other PPE-gear such as hard hats and safety glasses. Workers who wear earmuffs while operating in hot, humid types of environments will find that they become sweaty and hard to wear for long periods of time. Because of this added discomfort, some employees have the tendency to remove their hearing protectors to overcome the discomfort or obstacles in communication. Removing hearing protection increases the risk of being exposed to loud noises and suffering damage.

The pros and cons of universal ear buds

Like earmuffs, another common ready-fit option is disposable foam plugs. These ready-fit plugs are somewhat more comfortable than cumbersome earmuffs, but unfortunately also make communication difficult.

Compared to custom hearing protection, these earplugs have some very obvious disadvantages (overprotection, lack of comfort) and they are also a costly option — both financially and for the environment.

For example, a company of 50 employees that use four new pairs of foam plugs every day (new ones after each break) would spend around $86,000 on foam plugs over a period of four years, compared to $13,000 for custom earplugs in that same timeframe. That is a saving of over 80% in costs, and it prevents 192 kg of rubbish from going straight to landfill.

Why custom earplugs are a good solution

Industry requires PPE that enables workers to hear one another, stay aware of their surroundings and yet still be protected from dangerously high noise levels.

Fabricated using medically classified soft silicone material, custom-made earplugs achieve all this. Designed to offer comfort, discreetness and durability, these earplugs are made to suit a specific work environment, person and their individual ear shape. In addition to being cost-effective, advantages include:

• Easy for workers to communicate due to tuned filters
• Available in class 5 AS/NZS1270 tested
• No over-attenuation due to optimal protection
• A product that can be worn for an entire shift (comfort and communication)
• Doesn’t interfere with other PPE like glasses and hard hats
• Discreet fit
• Suitable for humid and harsh environments (no sweating)
   

Image credit: ©stock.adobe.com/au/Tomasz Zajda