Noise Reduction Rating – NRR


facebooktwittergoogle_plusredditpinterestmail

Hearing loss affects nearly one in ten Americans. This condition is usually caused by exposure to excessive noise. Shooting firearms is one of the activities that expose individuals to excessive noise. The noise levels that are produced when firearms are used can lead to permanent hearing loss. This makes it necessary to use hearing protection with good noise reduction rating.

Firearm Sound Levels

It is important to know how loud a firearm is to understand the need for hearing protection. The sound produced varies depending on the type of firearm used. Ammunition also determines noise levels. Sound levels are measured in decibels (dB). To comprehend just how loud a firearm is, it is essential to make some comparisons. A standard conversation is about 60 dB while a jet engine is at nearly 140 dB. On the other hand, when a firearm goes off, a shooter is exposed to 140 dB. This means that the firearm produces the same amount of noise as a jet engine. The Occupation Safety & Health Administration categorizes 140 dB as painful sound.

noise reduction rating - nrr

NRR indicates the level of sound being blocked

Painful:
170 dB = 44 Revolver
165 dB = 45 Automatic
160 dB = M-16
155 dB = 12 Guage Shotgun
150 dB = .38 Revolver
145 dB = .22 Rifle

130 dB = Jackhammer
120 dB = Jet Plane Take-off

Extremely loud:
110 dB = Machinery
100 dB = Chainsaw
90 dB = Lawnmower

Very loud:
80 dB = Alarm Clock
70 dB = Vacuum Cleaner
60 dB = Conversation

Moderate:
50 dB = Moderate Rainfall
40 dB = Quiet room

Faint:
30 dB = Whisper, Quiet Library

Shooters are also prone to tinnitus, which refers to ringing in the ears. Ringing ears are common and they can happen every once in a while. However, if the sound of a rifle going off makes your ears ring, it indicates that you are prone to hearing damage. Exposure to extremely loud noise once or over an extended period can cause permanent ringing.

Recommended Noise Levels

According to the Occupation Safety & Health Administration (OSHA), exposure to about 85 dB for eight consecutive hours can lead to permanent hearing loss. If the noise levels increase to 130 dB or higher, an individual can suffer from permanent hearing loss immediately. Hearing loss tends to go unnoticed in most cases because it is gradual and painless. It is often diagnosed when the symptoms are severe and the damage is irreversible. Hearing protection is recommended every time you are shooting a firearm. The devices designed to lower noise exposure should have the right Noise Reduction Rating (NRR) to protect your ears from damage.

What is Noise Reduction Rating?

Noise Reduction Rating refers to a measurement unit applied to determine hearing protection effectiveness. There are various devices that are designed to reduce sound exposure in various environments. These devices are usually categorized according to their capacity to reduce noise. Shooters need these hearing protection devices but they have to be tested and certified by OSHA and the American National Standards (ANSI). A high NRR number on a hearing protector indicates that it has a greater capacity to reduce noise.

How NRR Changes Noise Exposure

If you wear hearing protection when using a firearm, the level of noise you are exposed to is determined by the NRR rating on the device in use. It is important to understand that while NRR is measured in terms of decibels, the device you use to reduce exposure will not reduce sound levels by the exact decibels that are related with its NRR. This means that if you are firing a rifle that produces 140 dB and the hearing protection that you have on has an NRR 33 dB, the level of noise exposure is not reduced to 103 dB. To determine how much noise exposure is reduce, deduct 7 from the NRR on the device and divide the result by two. In this case, (33-7)/2=13. This means that your noise exposure reduces by 13 dB with the hearing protection. You will be exposed to 127 dB when you fire the rifle. It is advisable to use hearing protection appropriately to enhance noise reduction.

Hearing Protection Options

It definitely hurts when you shoot magnum revolvers or centerfire firearms without protection. This usually happens with new shooters or when you forget to wear your hearing protectors. The good thing is that gunfire tends to be short but it can still have a significant impact on your hearing. There are various hearing protectors available to protect your from ear damage.

Ear Plugs
These are a simple option that can help you to reduce the amount of noise that you are exposed to when you use a firearm. You can use cotton balls or purchase some custom fitted ones. They are popular because they are not obtrusive. Ear plugs are quite effective if they are custom fitted. You can find some that offer 32 dB NRR. If you want something light to protect your ear, they are ideal.

Earmuff Hearing Protection
They look like headphones and most shooters prefer them because you do not have to place them inside your ear. However, some shooters consider earmuffs bulky and obtrusive. You can choose earmuffs with foam ear cushions or liquid filled ear cushions depending on how much you want to spend. One of the main advantages of these hearing protectors is that you can use them with earplugs when you are using indoor ranges. This helps to reduce the noise exposure even further. Earmuffs have to be worn correctly with the band at the top of the head. This ensures that the ear is fully enclosed. The earmuffs will dampen most or all of the sound in the surroundings. This makes it difficult to have conversations or listen to your surroundings when you are shooting.

Electronic Earmuffs
These hearing protectors feature an in built audio amplifier. The amplifier runs on a battery. There is a tiny microphone in both muffs and they are designed to pick up external sounds and amplify them before they are fed to a speaker. You can control the volume of the speakers. An electronic circuit is used to block loud sounds and reduce their volume. This protects you from noise exposure. Electronic earmuffs are an ideal choice especially when you are hunting because you can hear everything around you.

Conclusion

You can continue to enjoy shooting without compromising the health of your ears. It is advisable to use hearing protection that suits your needs. There are various hearing protectors available in the market. Check the NRR on the protector before you make your purchase. Remember to use the hearing protection each time you use a firearm. The hearing loss may not be obvious but exposure to noise definitely damages your ears.

facebooktwittergoogle_plusredditpinterestmail