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It is often stated that you can reduce your daily noise dose by minimising the time you are exposed to loud sound. This is true. But it takes a very large reduction in time to produce a substantial effect. If you halve the time you are exposed to loud sound during a day, this reduces your daily noise exposure (dose) by only 3 decibels. Reducing it by three quarters lowers the daily exposure by 6 decibels. You would need to reduce the exposure time by nine tenths (i.e. 90%) to lower your daily exposure by 10 decibels.
It is much more effective to reduce the sound level. For example, the sound from an iPod can be reduced by 10 - 20 decibels, or more, simply by turning down the volume control knob. Suggestions and information on reducing noise levels are given below for common sources of sound that are loud enough to cause hearing loss.
Discos, live bands, amplified music and speech
When the sound is loud at discos, live bands, or anywhere else where there is amplified sound, you could ask for the sound level to be turned down. Ask the DJ, and if that fails, ask the manager. Point out that they could be sued if they cause people’s hearing to be damaged by exposing them to loud sound.
However based on our past experience, if they turn the sound down at all, it is usually only by a small amount, and it is normally turned back up again very soon afterwards. People that operate discos, live bands, shows and amplified sound do not seem at all concerned that their customers are being deafened. It will probably take a new law to force operators to reduce the sound to a safe level, or someone suing them for hearing damage and winning thousands of pounds in damages.
You could try lobbying the Government or the European Union to bring in a law that limits all amplified sound to a safe level - which probably means 80 dBA or less.
In the meantime, you should wear ear protectors whenever exposed to loud sound. The options are ear muffs, or ear plugs. Ear muffs fully enclose the ear and are very easy to put on. Ear plugs fit inside the ear canal, which means they are much less visible. However, it is much more difficult to fit them correctly. If they are not fitted correctly, they can provide considerably less noise reduction than they should. It is very common to see ear plugs that have not been inserted properly. In many cases, they have been inserted so badly that they provide little noise reduction. Details are given below on how to fit ear protectors correctly.
iPods / MP3 Players
It is very easy to reduce the risk of hearing damage caused by iPods / MP3 players. Simply turn down the sound volume control knob. The difficulty is knowing what volume or sound level is safe. Some iPod / MP3 players have a sound level limiter or allow you to enter a code that locks or limits the maximum volume. For some types of ipods, you can download software from Apple that limits the sound level. This prevents the sound level exceeding the maximum level that you set in the software. You could try using these where fitted.
ipods / MP3 players are usually sold with standard earphones that fit loosely in the ears. If wearing these, make sure that the player is never so loud that people around you can hear your music or that you can’t hear other sounds around you, like people speaking. If you use the type of earphones that have a rubber sleeve that seals the earphones to your ears, or headphones that fully enclose your ears, this guidance does not apply. This is because the seals prevent music escaping from the earphones so easily - it also stops external sounds getting into your ears so easily.
Avoid increasing the sound level after you have been listening for a while. We get used to sound after a short time. This means that it may not appear loud, even though it is. You can check by removing your earphones for a short time, then putting them back on. This will give you a better idea of how loud the sound is. This assumes you are in a relatively quiet area - it would not work if you were somewhere noisy like near industrial machines in a factory!
Do not increase the sound level to block out external noise. If external noise is a problem, you could try noise cancelling headphones or headphones with rubber seals. However, you should be extra careful that the iPod sound level is not too loud, and that you can still hear people speaking nearby. Also, using different earphones than those supplied with the iPod can alter the sound level considerably. So if you have set a maximum limit, this might need to be altered if you use different earphones.
Set the volume loud enough to hear clearly in quiet surroundings, and no louder. Try to keep the volume low enough that you can carry on a conversation with people nearby.
Immediately after finishing using your iPod, go somewhere quiet. If your ears are ringing, buzzing or hissing, it usually means the sound was too loud and could have caused some loss of hearing acuity. See “warning signs” above for more details.
Industrial Noise Control
Acoustic enclosures are a common method used to reduce industrial noise. They provide a large noise reduction. However their cost is very high. Also, enclosures restrict access and visibility, making it more difficult for workers to operate machines and this can impair productivity. It can also increase the time needed to carry out maintenance and breakdown repairs. An enclosure can also make it much more difficult to move raw material in and finished product out.
An alternative is to use a solution that reduces the noise at source using engineering noise reduction techniques and / or advanced technology. The main benefit is much lower cost than acoustic enclosures. The savings often amount to thousands of pounds. Because this type of solution involves very small machine modifications, it avoids all access and visibility restrictions. So there is no interference or restriction on machine operation, maintenance, or movement of materials and finished products into and out of the machine.
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