Noise-Induced Hearing Loss

Are You Sufficiently Protected Against Noise-Induced Hearing Loss?

Towards the end of their 30s, most people’s ability to hear begins to deteriorate. The process, however, is a gradual one, and in most cases, those affected will experience no significant difficulties until quite late in life. Known as presbycusis, it is simply another manifestation of the aging process and, much like wrinkles, will be more marked in some subjects than in others. Of far greater concern than the effects of the advancing years, however, is the fact that the noise-induced hearing loss (NIHL) has become the most prevalent form of auditory impairment. Much of that concern stems from the fact that NIHL is affecting subjects from an early age. In the US, for example, it has been reported in children of ten and even younger. Still more prevalent among adults, it has become the most common form of industrial injury and yet, with the right safety measures in place, NIHL is a condition that is preventable.

Traditionally, it has been those workers who are required to operate in a consistently noisy environment that are most at risk of noise-induced hearing loss. In all cases, sounds in excess of 85 decibels pose a threat, the severity of which increases with volume, length of exposure, and repetition. In South Africa and many other countries, there are now regulations that define the measures employers need to adopt to reduce the risk of NIHL in their staff. Despite the rules, it remains prevalent, and in some cases, appears to be on the increase.

The failure of preventative measures can be attributed to three main factors. Workers may not fully accept the need for protection, earplugs and ear defenders may interfere with communication and so are often abandoned, or the measures in place are not sufficiently effective. Whatever the explanation, noise-induced hearing loss will obviously remain a threat. So, what could be the solution? What constitutes adequate protection and how can an employer ensure that those workers who are at risk will embrace it?

Each of these three problems is going to require its own solution and the first of these must be education. Employees need to understand the nature of NIHL and that it is the inevitable fate of anyone who, day after day, is exposed to excessively high volumes of sound for as much as 8 hours at a time without effective protection. Workers need to be fully aware that noise-induced hearing loss is an irreversible condition that, in just a few years, could see them unfit to continue in their jobs.

Once the education has been completed, the next step is to select the best possible protection, and this is not likely to be found on the shelves of a local hardware supplier. Neither standard earplugs nor earmuffs are likely to prove effective, as they tend either to impede sounds too effectively or not effectively enough. To provide the necessary degree of protection against noise-induced hearing loss whilst permitting the wearer to conduct a conversation, should the need arise, any earplugs used will need to meet some important criteria.

They will need to fit properly and tightly, yet comfortably. This means that they must be tailored to match the precise contours of both the left and right ears of each wearer to occlude all noise. Even this, however, is not good enough. An effective product must permit the wearer to hear speech without the need to remove it, which would then re-expose a wearer to the risk of noise-induced hearing loss.

The difficulty can be overcome by the inclusion of an attenuator or filter. There are different types of filters that attenuate sound differently. Passive filters bring noisy sound levels down, so that speech is more understandable, and electronic filters dampen impact sounds like gunshots, yet allow the passage of sounds at lower volumes including, of course, speech. With an adequately informed workforce and these effective custom-made earplugs, it only remains to introduce some form of monitoring.

H.A.S.S. Industrial is a specialist in the manufacture and supply of custom-made hearing protection. The service includes a comprehensive hearing conservation management programme that begins by assessing the customers’ needs, discussing noise-exposure levels and the auditory function of those exposed. It also creates awareness of the causes and consequences of noise-induced hearing loss and then implements personalised Noise-Ban custom-made earplugs. Once fitted, these are tested for a proper seal in each ear and the filters are adjusted for optimum efficiency. The programme’s effectiveness is then monitored annually. Need to learn more? Give H.A.S.S. Industrial a call.