With the many different types of guns and ranges, finding the recommended NRR (NRR stand for Noise Reduction Rating) for shooting can be tough – especially if you are new to the sport. There are a few things to consider and it is best to fully understand what NRR is, how it is calculated, the recommended NRR for different types of shooting (indoor vs. outdoor ranges) and how loud noises can create permanent hearing damage.
In short, there isn’t a single recommended NRR for shooting as much as there is a range. This NRR range starts at 28 and goes up to 31 NRR depending on the type of gun you are shooting and the environment.
What is NRR?
NRR of Noise Reduction Rating is standard measurement rating tested by the American National Standards (ANSI) and governed by the Occupational Safety and Health Administration (OSHA). This rating is used to better understand how effective hearing protection is at protecting the human ear from high decibel sounds.
(NRR) Noise Reduction Rating Calculation
Although the NRR number does not translate into a 1 for 1 reduction in noise decibel level, it does generally meet the stated number within a very minor margin of error.
For example, if you are on a shooting range with a decibel level of 156 (12 gauge shotgun), and you are only wearing ear protection rated NRR 33, this does not simply decrease what you hear to 126 decibels (156 – 33 = 126).
To calculate this correctly, you need to:
- Locate your NRR number (in this case = 33)
- Subtract seven (33 – 7 = 26)
- Divide by two (26/2 = 13)
- Going back to the example: (156 – 13 (new NRR) = 143)
For more information on how to calculate NRR, please visit the OSHA website: HERE
Is Higher NRR better?
The higher the NRR, the better that hearing protection should be at reducing noise and protecting your ears. The higher the number equates to a greater ability to guarding your hearing from high decibel related damage.
What is the Highest NRR Rating?
The highest NRR can be found in earplugs (33) and ear muffs (31). When earplugs and ear muffs are combined, you can increase that NRR number to 36. These numbers reflect a perfect scenario in which the user properly wears and secures the hearing protection. As you might imagine, the closer the hearing protection is to your body (inner ear), the better it will perform. This is why earplugs can give a higher NRR.
Hearing Protection Chart
As you can see in the chart below, the decibels emitted by a series of everyday objects and actions can range from the normal to the extreme. The normal conversation decibel level is 65 and only 35 more decibels to 100 do you finally reach the level of a motorcycle.
We’ve all heard a loud motorcycle and covered out ears. In fact, most motorcyclists wear hearing protection. And, for good reason. At 100 decibels you can suffer severe hearing loss and damage after a 1 hour drive.
Now, let’s think about guns.
They are obviously very loud and top out at the higher end of the decibel chart. Nearly all firearms create a decibel level exceeding 140. At this level, you will (not may) permanently damage your hearing. If that wasn’t enough warning, a shotgun can reach decibel levels of 175.
NRR Rating for Shooting (Most Common NRR)
By now you know that all hearing protection requires an NRR number to give the buyer an idea of the level of hearing protection they can expect. Shooting ear protection with an NRR range from 28 to 31 is recommended for indoor shooting. Why – you might ask? Well, as you might imagine, shooting indoors creates a lot of echo and you are much closer to other shooters.
If you’ve ever been to an outdoor range and and indoor range, you will quickly feel and hear the difference. It is still recommended you use double ear protection in an outdoor range just to be careful. You can still damage your hearing even without the extreme echo.
Are Earplugs Good Enough for Shooting?
Yes, an earplug with an NRR of 33 should be enough for shooting. However, it is actually recommended that shooters wear double protection. What does this mean? Well, it simple means you should wear an earplug and ear muffs. This is actually a recommendation by the National Institute for Occupational Safety and Health and for good reason. The decibels coming from most guns far exceeds what a single hearing protection device can protect you against. Doubling up with earplugs and ear muffs will increase the overall NRR and help prevent hearing damage.
How Hearing Loss Occurs (From Loud Noises)
Loud noises, from a gunshot, can cause devastating hearing loss and damage. You might be wondering how a loud noise damages hearing. Well, at higher decibels the sound waves can damage the hair cells in your ear. After a sound enters your outer ear and makes its way into your inner ear it become amplified. This amplification passes through cochlea fluids where they meet the hairs with nerve cells. These cells convert those vibrations into brain signals that create sound. It is your brain that differentiates between sounds, words, and pitch.
If you are exposed to extreme sounds with out hearing protection, you can damage the small cells and prevent from sending the brain signals – resulting in partial or complete hearing loss.
As you can now see, there are a range of NRR numbers to consider in addition to many factors when buying shooting ear protection. However, if you are in a pinch and want a go-to option – stick with hearing protection with at least an NRR of 33 to be safe. Also, always remember to double-up the hearing protection whether you are at an indoor shooting range or and outdoor shooting range.