Hearing protection guide

[Soybomb]

I made this up a few days and posted it on another forums so I apologize if you're already see it, but I'm not sure everyone has a few posts in another thread made me think it might be welcome information here.

I know when I first started out I had to look around a bit to decide what was important in hearing protection and what to look for so I thought I'd compile some information here in hopes that it might help others.

Measuring Sound: Loudness is measured in decibels (dB). This is logarithmic measurement, every increase of 3dB doubles the sounds intensity. Generally however it will take a 10dB increase for us to perceive the volume as twice as loud.

Lets look at some common sound levels:
breathing at 3m - 10dB
whispering - 30dB
office or restaurant - 60dB
expose past this point can cause hearing damage - 85dB
lawn mower - 90dB
15 minutes of exposure can cause hearing loss - 100dB
1 minute of exposure can cause hearing loss - 110dB
accelerating motorcycle at 5m - 110dB
rock concert - 120dB
threshold of pain - 130dB
jet engine at 30m - 150dB

Gunshots and hearing:
1000 sound impulses max a day at this level per OSHA - 130dB
.22lr rifle 134dB
100 sound impulses max a day at this level per OSHA - 140dB
.223, 55GR. Commercial load 18" barrel 155.5dB
.243 in 22" barrel 155.9dB
.30-30 in 20" barrel 156.0dB.
7mm Magnum in 20" barrel 157.5dB.
.308 in 24" barrel 156.2dB.
.30-06 in 24" barrel 158.5dB. In 18" barrel 163.2dB.
.375 18" barrel with muzzle brake 170 dB.
.410 Bore 28" barrel 150dB. 26" barrel 150.25dB. 18" barrel 156.30dB.
20 Gauge 28" barrel 152.50dB. 22" barrel 154.75dB.
12 Gauge 28" barrel 151.50dB. 26" barrel 156.10dB. 18" barrel 161.50dB.
.25 ACP 155.0 dB.
.32 LONG 152.4 dB.
.32 ACP 153.5 dB.
.380 157.7 dB.
9mm 159.8 dB.
.38 S&W 153.5 dB.
.38 Spl 156.3 dB.
.357 Magnum 164.3 dB.
.41 Magnum 163.2 dB.
.44 Spl 155.9 dB.
.45 ACP 157.0 dB.
.45 COLT 154.7 dB.

The first thing anyone has to notice is that firing any gun, even a .22lr in a rifle without hearing protection is loud enough to cause hearing damage.

Protection: In general ear plugs are better at blocking low frequency noise, ear muffs are more effective against high frequency. Ear protection in the US will have a NRR number assigned to it, this is the dB drop it should give you. For example if you're around 60dB of noise and wearing NRR 30 plugs, your ear should be getting 30dB of noise.

Doubling Up: Some shooters chose to double up on their hearing protection. Personally I shoot indoors and find this to be especially wise. Sadly however you can't just add the NRR values of your hearing protection to get the total reduction value. The OSHA guideline is that you get to add 5dB of NRR to the highest rated protection device with the addition of a second one. For example wearing plugs rated 33nrr and muffs rated 30nrr give a total nrr of 38dB. Some speculate the gains are greater and that estimate is conservative. On the surface this doesn't seem like much, but when you consider that 3dB is a doubling of sound level, it is indeed worth quite a bit.

For example lets say you're indoors shooting a 9mm with 25dB muffs on. Your 160dB sound has been attentuated to 135dB in your ear. You're at a maximum of 500 impulses at at that volume before hearing damage according to OSHA. If there are others shooting at the range that day and you intended to go through a hundred or more rounds yourself, its quite easy to see how you could exceed the allowed exposure levels that day. Things get even worse if someone on the range with you is shooting magnum rounds. However if you had the 38dB of protection discussed earlier from doubling up you would be exposed to 122dB of sound from each of your shots and would be safe well over a thousand shots.

If you have comfort problems with ear plugs an audiologist should be able to mold a custom fit set of ear plugs for your ears. It may well be worth it for the frequent shooter.

Protests: Now some of you will say you've been shooting for years with little to no protection and haven't noticed a problem. To that I would point out that hearing loss is gradual and often starts with higher frequencies first. You could very well have hearing loss that you just don't realize yet. Some people will get tinnitus (rining in the ears) and it will be quite noticeable. An exam might be recommended if you question it. The final thing to keep in mind is when you get to the truly damaging sound levels, is that the damage done to your hearing is permanent and cumulative. It will get worse every time you get to those damaging levels again.

Reference material:
http://www.answers.com/decibel&r=67
http://www.mckinley.uiuc.edu/handouts/noise_ears_hearing/noise_ears_hearing.html
http://www.american-hearing.org/name/noise_induced.html
http://www.pro-am.com/Catalog/Product_Advice/Hearing_Protection/willson1.asp
http://www.freehearingtest.com/hia_gunfirenoise.shtml
http://www.thehighroad.org/showthread.php?t=183414

I hope this can be a decent reference to those who are getting started or wanting to see if their hearing protection is effective enough.

I just got in some replacement protection today that I'd like to point as being quite effective for me:

First is a package of Leightning L3 muffs with a NRR of 30dB ($18.46) and second is 100 pairs of Howard Leight plugs with a nrr of 33dB ($24.01). Both seem comfortable and have some of the highest nrr values you can find. I ordered them from http://www.tradingpostsupply.com and the shipping was fast. I previously ordered some leightning muffs from a different seller and had nothing but problems from the other seller (consider that fair warning if you use froogle or ebay to try to find a cheaper price). Their item number for the plugs is HLR33133 and HLR03318 for the muffs if anyone wants to try them. My only complaint is you can forget about using the muffs with a long gun.

 

[Q-Lock]

I feel like I've read most of this information on here before...but why the plug for certain companies? If this is just to inform us of the hearing damage possible with firearms...then why advertise a specific product?


regards,

 

[hso]

Soybomb,

Thanks. The material has been presented several times before, but you've condensed it well.

Q-Lock,

I can answer that. Not all products are created equal and many folks can't get them to perform as well as advertised by the manufacturers. Much of that comes from improper insertion of ear plugs and improper wearing of muffs, but some comes from the wholly subjective way in which the NRR is established for hearing protection devices by the manufacturer. Since they want to be protective they want the highest numbers possible on their NRRs. This leads to overstatement of their protective properties. The simple foam cylinders provide the best protection of all the plugs in spite of having been around longest of all the foam plugs.

I would caution about blanket endorsement of custom molded ear plugs. Many custom plugs just aren’t molded properly and provide less protection than the cheap foam plugs.

If a plug, custom or cheap foam, doesn’t reach the bend in the ear canal they will have a serious reduction in protection compared to what was advertised.

While Howard Leight products are excellent they are not the only quality manufacturer out there. EAR, Moldex and Peltor are good manufacturers also. Not all of any manufacturer’s products are as good as others in their own line.

Stay away from any disposable ear plug that you do not have to roll up small to fit into the ear canal. Ear caps and “plugs” on bands are not worth the money.

 

[Soybomb]

I feel like I've read most of this information on here before...but why the plug for certain companies? If this is just to inform us of the hearing damage possible with firearms...then why advertise a specific product?

Great, I figured some new shooters might want a nice condensed guide. I know it would have saved me some time. No particular reason I wound up picking the bilsom/leight products. I found many people on here suggested the leight muffs, I tried them, they were comfortable, I found a retailer that sold very high nrr plugs and muffs at what I found to be a good price. Certainly feel free to list others you find to be good here. I felt like it was nice to compile a brief tutorial, but I'm not nice enough to put together a list of several brands and places to buy them. With the information given people can decide what nrr they need and shop for themselves.

 

[Trebor]

Good post. There's a lot of ignorance and misconceptions out there and this will help.

Hso, I agree that not all products are equal. I've also found the simple cylindrical foam plugs work the best for me. Even though they aren't rated as high as other brands and types of plugs, they fit in my ear better without dislodging themselves. I always "double up" plugs and muffs and I can notice a difference with the same pair of muffs between the cylindrical plugs and the more expensive plugs. The cheap ones cut more of the noise.

It's also important the insert the plugs properly. You have to rub each plug between your fingers to make it narrower before you insert it into your ear. After you insert it, hold it in place for 10 seconds to keep it from dislodging itself slightly and damaging the seal while it expands.

For muffs, I like the Peltor brand muffs myself. I was using the "Ultimate 30" and I'm now switching to the Peltor Aero 31 line.

 

[Dan0076]

Great post. I was thinking about posting a 'protect your hearing' thread today. But I wouldn't have been able to post something so informative.

I just had a check up for a new job I'm starting next month. I had to have my hearing checked and got a good talking to from he Dr. when on my right ear for 4K the number was 30. He said that I need to be careful about protecting my hearing and a dip like that means that (and I'm paraphrasing here) I'm showing signs of early hearing loss.

From now on, I'm doubling up when shooting center fire. But I'll just stick with the foamies with .22lr.

Thanks for the info Soybomb

 

[GrOuNd_ZeRo]

Hearing loss??

I am used t loud noise, I listen to my headphones and other things.

I took my new pistol to the range yesterday around 8:30pm and fired half a box of ammunition, it was a .40S&W and after a few shots my ears were definitly ringing, I woke up with problems of hearing in my left ear and did one of the free hearing test and I aparently can't hear tones of 3Khz, I hoped this was temporarilly but it didn't return after a night of sleep, it's 1:00pm now the next day.

After this short session, may I have damaged my ears already? it would be pretty upsetting but I didn't realise such short expossure to gunfire would do it...

I had a session with a 30-30 and a 12ga a few years back, my ears were ringing for a while and had some similar problems but they resolved them selves...

What do you suggest I do?

 

[hso]

GrOuNd_ZeRo,

You may have screwed yourself irrevocably.

Make an appointment with an audiologist and get your hearing tested. Regardless of what they find, any hearing loss after a few days is probably permanent and you'll never get it back. Pray that the ringing goes away.

From here on avoid any exposure to hazardous noise levels. NEVER shoot without hearing protection. If you care at all about your hearing then wear plugs and muffs properly whenever you shoot.

 

[GrOuNd_ZeRo]

Damn it, I never had this happen before with any other firearms, granted this was the first time I shot a pistol...

However, I do believe I had some temporarilly hearing loss when I shot that 12 ga four years ago, it lasted till the next day I think and gradually got better, the ringing is definitly gone.

hopefully my ears wont be too bad...but otherwise I learned a lesson here...

 

[One of Many]

I will disagree with the comment that muffs can not be used with rifles and shotguns. I use muffs for all of my shooting, and double up with plugs when shooting the louder guns, even outdoors. The gun stock will effect the fit of the muffs to the head, resulting in a decrease in effectiveness on the side adjacent to the stock, but the muffs still provide better protection than without the muffs.

The muffs will lose some of their noise attenuation due to the temples on eyeglasses; it has been stated that there is a 5 dB drop in effectiveness due to the eyeglass temples breaking the seal between muff and head. Use of the ear plugs will compensate for the noise attenuation decrease due to the temples. Since every shooter should be wearing eye protection, this 5 dB decrease for muffs should be considered a universal reduction in advertized NRR ratings for shooting sports.

The roll up foam plugs work very well, but care is required in their use; it is possible to insert the roll up foam plugs so deeply into the ear canal, that they can not be removed with the fingers - this requires assistance from someone else with tweezers to remove these deeply inserted plugs. The roll up foam plugs that I have seen have all been relatively short; a roll up foam plug with twice the standard length would alleviate this problem.

There are roll up foam plugs available that are intended for reuse; these have a soft plastic cover that is washable, and there is usually a string connecting the plugs together, that can be placed over the head to prevent loss. These plugs typically do not have as high a NRR rating as the throw away foam plugs; they are however much easier to remove (with the strings) when inserted deeply into the ear canal. Used in conjunction with muffs they are a good choice.

Custom molded plugs typically have a much lower NRR rating than the roll up foam plugs, even when properly fitted by an experienced audiologist. They have their place, because some people have very small ear canals, or other problems that preclude use of the throw away plugs. Most custom fitted plugs are used by people that must wear hearing protection for hours at a time, usually as a job related matter; the comfort of molded plugs is a factor in selecting them - some protection all of the time, is better than great protection some of the time, and no protection some of the time.

I recently replaced a set of damaged muffs, and found a good set (NRR Rating 31 dB) bearing the Remington Brand at a Gander Mountain store. These are not fancy muffs (they are not pretty), and they do not fold up into a small pocket sized unit for storage (in fact they are bulky and hard to store). They cost several dollars more that the some of the well known brands used by sportsmen, but their NRR rating was as much as 7 dB better than the lower priced models with the well known brand names attached. Spend the money to buy the best hearing protection you can find; your hearing is more important than how good you look, or how easy it is to store the muffs when you are not using them.

Electronic muffs typically do not have as good a NRR as a plain muff; the better electronic versions have a NRR similar to the worst of the plain muffs available, and cost as much a ten times more. The electronic muffs usually claim to clamp noise impulses to less than 85 dB; that is what the electronics will do, and it does not address tha ability of the shell itself to reduce the ambient noise level. When the base NRR rating of an electronic muff is around 20 dB, and a gunshot produces 150 dB of noise, the electronic muff will block 20 dB of noise, resulting in a 130 dB exposure to the ears; the clamping effect of the electronics at 85d dB is swamped by the inability of the shell to reduce below that level.

Electronic muffs are best used in a moderate noise environment, not in an extremely high and sporadic noise environment such as shooting, where the noise pulses are tens of dB above the ability of the electronics or the shell of the muff, to attenuate the noise to safe levels. Most of the electronic units work by clipping impulse noises at 85 dB, and amplifying the general noise level to allow specific frequency ranges (such as voice) to be heard at a relatively higher volume than the background noise. In effect, you are listening to all of the noise all of the time, at higher dB levels than you would get with plain muffs.

Constant exposure to the noise of gunfire will damage hearing, even if muffs and plugs are used religiously. The hearing protection will delay the effects of the noise exposure, and will reduce the severity of the damage compared to using no protection at all. The damage may not be noticed in daily activities for a very long time. As noted in one of the previous postings, hearing damage is cumulative, and any exposure over 85 dB is damaging.

 

[silliman89]

I am used t loud noise, I listen to my headphones and other things.

There is no way to get "used to" loud noise. It's only possible to damage your hearing so that loud noise no longer sounds loud to you. You may have been doing this for years with your headphones.

I second getting a hearing test as soon as possible. The rest of your life is a long time to be going "Huh, what'd ya say?" all the time.

 

[slzy]

in movies the drill instructor is always intoning Iiii Can'nttt Hearr Youu, was probably true ,if he was an old hand.

 

[mondocomputerman]

Good post. Thanks for sharing.