Health & Safety in Noisy Environments

The hearing is our most important organ of communication, but hardly anyone thinks consciously about their ears. Yet they are high-performance precision instruments. When likened to a pair of scales, their possible measuring range is from 1 milligramme to 1000 tons! But this organ was not designed for our loud civilization. The main problem: hearing damage once suffered is usually irreparable.

Apart from the pure facts we grasp by hearing, we also get the emotion behind a message and are able to react appropriately. The perceived movement of the lips is normally insufficient for complete understanding of a message.

Our sense of hearing warns and alarms us. Warning cries, an approaching car, the ringing of the telephone, a siren or a call from a doctor - everything passes through the ear. Good hearing helps us in spatial orientation. From the volume and time differences of the signals arriving at our two ears we can perceive the direction a noise is coming.

How does hearing protection work?

Basically there are two types of hearing protectors:

Passive Ear Muffs - dampen the sound, which means that all noises are reduced as they pass through the ear muffs. It is important that the hearing protection used provides enough attenuation to protect the hearing. But it is also important that it doesn’t give attenuation so high that you are overprotected. Overprotection can prevent you from hearing your workmates, alarms and other important signals. The recommended sound level under the hearing protector is between 70 – 80 dB.

Active [Electronic] Ear Muffs - These have a built-in electronic circuit limit noise but let you hold normal conversation with other people – without having to remove your hearing protector. Built-in level dependent amplification amplifies speech and other harmless sounds while protecting against harmful sound levels. To prevent harmful noise levels, the internal speaker output is limited to 82 dB.

Exposure Times

Noise induced hearing loss provides a lot of negative factors, both to the employer and the individual. First of all by human suffering, but also stress, pain, tinnitus etc can lead to social handicap. The ears are not adapted to the noise levels we are being exposed to in our every-day environment. Noise from industries, traffic and leisure noises from engines, shooting & hunting, loud music etc is damaging our hearing.

Today there are a lot of protective products available that should ensure noise induced hearing loss is totally un-necessary. By law, the first action level is at a daily personal noise exposure of 80dB(A) during 8 hours. In this situation hearing protection should be offered. Because of individual differences, some people are more sensitive to noise than others.

• Lower Exposure Action Level 80 dB[A] / 135 dB[C] - Where noise exposure exceeds the lower exposure action values, the employer shall make individual hearing protectors available to workers.
• Upper Exposure Action Level 85 dB[A] / 137 dB[C] - Where noise exposure matches or exceeds the upper exposure action values, individual hearing protectors shall be used!
• Exposure Limit Values 87 dB[A] / 140 dB[C] - Under no circumstances shall the exposure of the worker exceed the exposure limit values! At work in circumstances with more noise exposure the individual hearing protectors shall be so selected as to limit the exposure at the exposure limit values.

If you are exposed to any of the above action levels without wearing hearing protection, there is a great risk that you may suffer permanent hearing damage.

Examples of Noise

85-100dB - Light tractors & Lawnmowers, Electric hand tools, Workshop equipment, Light garden machinery
85-120dB - General manufacturing industry
100-120dB - Heavy tractors, Steel construction, Road construction, Engine rooms on ships
110-120dB - Steel works, Forestry equipment (chainsaws, saw mills), Textile industry, Paper & printing works, Concrete processing, Heavy plant (bulldozers etc.), Pneumatic drills/concrete brakers
115-130dB - Mining & quarrying
120-150dB - Airports, Jet engines, Motorsports

Points to consider

Below are some point to consider for choosing the right headset.

Comfort
Choose a hearing protector that you are prepared to use 100% of the time you are exposed to high noise levels.

Compatibility
Select a hearing protector that works with your other equipment such as mobile or DECT phone, communication radio, safety goggles, helmets, visors, respiratory products etc.

Noise Attenuation
Check that the product has appropriate noise attenuation. It should only be high enough to protect you from hazardous noise levels. To high attenuation can make you feel isolated and shut out ambient sounds such as alarms and other important signals.

Motivation
Through training and information it is easy to be motivated to protect the hearing.

Maintenance
By replacing hygiene kits and keeping the ear muffs clean they will be more pleasant and hygienic to use.