Excessive noise and hearing loss
Excessive levels of noise can damage the sensory “hair” cells that process mechanical energy into the tiny electrical nerve impulses that our brain perceives as sound. Hearing loss caused by exposure to noise at work continues to be a significant occupational illness. Exposure to noise may also cause tinnitus, which is a sensation of noises (such as ringing or buzzing) in the ears. This can occur in combination with hearing loss. Providing adequate hearing protection for your employees is vital in order to avoid the shortterm disruption of employee ill health, the longer term likelihood of employees having permanently impaired hearing, and the possibility of costly future litigation against the employer.
The dangers of over protection
It may be tempting to pick the hearing protection with the highest level of protection (or attenuation), however ‘over attenuation’ can bring its own problems. If the sound level at the ear is reduced too far, the wearer can become isolated, unable to hear colleague’s voices, moving vehicles, warning sounds, or alarms.
Changing regulatory requirements
Under the Safety, Health and Welfare at Work (General Application) Regulations 2007 (S.I. No. 299 of 2007) a Limit Value of 87dB(A) at the ear must not be exceeded, and hearing protection must be made available where the sound levels are at or above 80dB(A), and strictly enforced where the sound levels reach or exceed 85dB(A). Whilst a reduction in sound level by 5dB(A) may not at first glance appear significant, it is worth noting that a reduction of just 3dB(A) roughly equates to halving the sound energy level.
Hearing protection range
Our hearing protection products are designed to provide protection, comfort and ease of use. Sometimes you may have to use hearing, head or face protection products together. To meet this need we also have a selected range of high quality safety helmets, visors and face shields.
Controlling noise at work It is common practice that a “real world” derating factor of 4dB be
applied to all hearing protection equipment. This means that when calculating the actual protection level offered by hearing protection equipment, 4dB should be deducted from the manufacturer’s own predicted attenuation figure.
The reason for doing this is that it is believed that not everyone will achieve the same level of attenuation with an identical piece of equipment. If the hearing protection equipment is not correctly fitted, then a lower level of protection will be achieved. Protection levels will also suffer if the hearing protection equipment is dirty or poorly maintained or if there are compatibility issues with other personal protective equipment, all of these will potentially have a significant impact on effectiveness.
Another way of applying “real world” attenuation and derating is to add 4dB to the calculated sound pressure level (LA) at the ear under the hearing protection equipment worn. However it is
important to note that derating does not apply to the assessment of hearing protector performance against peak noise.
Single Number Rating (SNR)
This is a general form of rating a products performance. In short the higher the SNR the better performance of that specific product across a range of noise frequencies. If a product performs with an SNR rating of 33 it may not give 33 decibel reduction of noise at all frequencies. The performance data associated with H, M and L give the user an indication of noise reduction at the High, Medium and Low frequencies.
Comparison of Old Directive (86/188/EEC) to New (2003/10/EC)
HEARING PROTECTION METHOD
OLD DIRECTIVE
Noise level
NEW DIRECTIVE
Noise level
Warning Signs Posted in Work Areas
90 dBA
85 dBA
Hearing Protectors Available
85 dBA
80 dBA
Hearing Protection Required
90 dBA
85 dBA
Training of Exposed Workers
85 dBA
80 dBA
Noise Reduction Program
90 dBA
85 dBA
Protected Exposure Limit
N/A
87 dBA
European Standards
All listed Hearing Protection is tested and marked to the relevant European Standards and CE Marked
EN 352 Part 1 - Ear Muffs
EN 352 Part 2 - Ear Plugs
EN 352 Part 3 - Helmet Mounted Ear Muffs
EN 352 Part 4 - Level Dependant Ear Muffs
EN 352 Part 5 - Active Noise Reduction Ear Muffs
EN 352 Part 6 - Ear Muffs With Electrical Audio Input
EN 352 Part 7 - Level Dependant Ear Plugs