If you work in a loud environment, or even if you're sometimes exposed to loud noises, hearing protection is essential. Hearing protection devices work by reducing the energy of sound waves reaching your inner ear. If sound waves have too much energy, they can damage the sensitive machinery of the ear, leading to progressive hearing loss and, sometimes, deafness. 

Choosing the right hearing protection, however, isn't always straightforward. Not only are there a range of products on the market, but it can be challenging to know which level of protection you should choose. That’s why it’s important you consult a hearing instrument specialist to determine which solutions are best for your specific needs.

Find out how much noise reduction you need

The first step toward choosing the right hearing protection is to find out how much noise reduction you need. 

Scientists measure the volume of a sound on the decibel (dB) scale. The noise of regular conversation is about 55 decibels. This level is in line with that which the human ear evolved to handle. 

The modern world, however, is full of noises which vastly exceed that of normal conversation, many of which are too loud for our ears to process safely. When sounds get above about 85 dB, the length of time that you can safely exposure yourself to them starts to fall.

A person shouting or a lawnmower might generate a sound of around 91 dB – above the safe limit. The HSE recommends, therefore, that you don't listen to these noises for more than two hours at a time. Electric drills come in even louder at 94 dB – a level that HSE says you shouldn't expose yourself to for more than one hour. 

As the noise level rises, the length of exposure time falls. You should only listen to a belt sander producing noises above 103 dB, for instance, for 7.5 minutes or less. 

The first thing to do, therefore, is to work out how much noise you're exposed to and how much noise reduction you need to get you below the safe, 85 dB level. All ear protection products come with a noise reduction rating or NRR. The NRR is an estimate of how many decibels quieter the sound reaching the inner ear is compared to the ambient noise. So, for instance, if you're using a 103 dB belt sander, you'll want hearing protection with an NRR of 18 to get you back down to the 85 dB acceptable limit. 

Apply a conversion factor to the NRR

The second step is to work out whether the noise reduction you get is comparable with the stated noise reduction rating. Unfortunately, the number quoted on the packet is often at odds with reality, with the NRR typically being higher than the actual figure. 

Most hearing instrument specialists advise that you include a conversion factor in all your calculations to get the true noise reduction of any hearing protection that you buy. The true noise reduction rating has the following formulate: 

(NRR-7)/2 = true reduction

The formula, therefore, dramatically reducing the total sound reduction reaching your ears for the vast majority of devices on the market. Most people, therefore, choose the highest-rated NRRs possible – typically between 30-32 depending on the type of device you want. 

Choose comfortable and convenient hearing protection

The final thing to think about is practicality. Which type of hearing protection is most suitable for the situations in which you'll wear it?

In general, there are two broad categories of hearing protection: earplugs and earmuffs. Earplugs are small foam or silicone devices which you insert individually into each ear. The foam variety requires you to screw up the end of it, push it into your ear, and then wait for it to expand to block the ear canal. Some earplugs have a band or piece of string connecting them.

Earmuffs, on the other hand, are different. Earmuffs look a lot like regular headphones but have the sole job of cancelling out noise from the environment. Because earmuffs sit over the top of the ear instead of in the ear canal, they tend to have slightly poorer noise cancellation performance. 

Earmuffs are an excellent solution for building sites and industrial applications because of how easy they are to wear. Operatives can just pick them up, place them over their ears, and get on with work. Earplugs are best for one-offs or situations where you want discreet noise protection. 

If you want to learn more about hearing protection, call us in Mechanicsburg at 727-602-3899 or Carlisle at 717-245-2437.