Two common forms of protection against noise are earplugs and earmuffs. These are available in a wide range of applications,
materials and prices. Unfortunately, these two methods of
HPD (Hearing Protective Device) provide less than 20% of the human body needs. In fact, using these HPD can cause, in course of time, a permanent damage, and the best evidence is that although hundreds of HPD''s are available in the market, reports clearly show that noise damages the hearing of millions around the world: Noise is the most common occupational disease and the second most self-reported occupational injury! (According to the National Campaign for Hearing Health). Noise is the major cause for
Tinnitus , Vertigo, Jet Leg and other psychosomatic diseases (even a specific type of cancer was found as caused by noise). Noise disables communication and none of us can conduct a phone conversation in a noisy environment. Governments pay billions for lost of production and social security lost income. Noise is considered to be one of the worst environmental pollution worldwide. Its impact on the comfort and health in modern life is significant (White paper European transport policy for 2010). http://cordis.europa.eu/eoi/dsp_details.cfm?ID=34072 The problems of the current existing HPD''s are well known to modern science and are not limited to the followings:
1. All types of ear plugs and earmuffs either completely block the ear canal or prevent fresh air from entering the ear. It is clear that current HPD''s do not allow the minimal ventilation required to the human ear. Since the human ears must remain open and ventilated. (God created man with open, ventilated ears!) Therefore, any attempt to seal the ear canal will cause bio chemical, physiological reactions that affect the human body. For the short time of use a sealed ear causes an uncomfortable sensation for its users who usually report their ears etch and get warm.
2. None of the existing HPDs block the ELF, (extremely Low
frequencies), or
infrasound. These are know as the most dangerous frequencies and yet, no solution for this risk.
3. No prevention of medical conditions caused by noise and transferred to body through the ears. Tinnitus, Vertigo, Jet Leg and other psychosomatic diseases can not be prevented using any of the HPD.
4. No protection from air pressure changes & shock waves.
5. Bone conduction noise transmission is not blocked by HPD.
6. NRR (or SNR) limitation. This measurement provides a limited protection in specific range of frequencies in which the HPD attenuates between 10 to 30 dB (as tested in labs only). No attenuation for all frequencies and no solution for those who are exposed to dangerous noise (In these case even attenuation of 30 dB will leave the user unprotected).
7. HPDs disable communication and do not allow users to communicate normally if at all. Inability to communicate in noisy working places affects the workers motivation and reduces his productivity. It seems that what current HPDs offer is based on a "No Theory". Even the electronic earmuffs do not provide the needed protection from the same reasons above.
The above arguments lead to the inevitable conclusion that there is no real protection for noise. Industrial PPE (Personal Protective Equipment) companies invest millions in R&D hoping to find a cure to this hazard; the Academic world provides many articles emphasizing the urgent need for such a solution while demonstrating the magnitude of the phenomena. It was only in University of Salford, UK (located next to Manchester) where a Swiss - Israeli scientist called Adam Aloofi (Prof.) demonstrated a unique device that really does the work. Members of the Noise Lab in the university claim that his solution is based on a bio acoustical theory that provides a full protection to the auditory system. The device specificaand theory were never exposed to the public and will be available to all once the Professor''s research is over.