May I ask a question of our FR shooters re hearing protection?

[LouAvul]

I've damaged my hearing from unprotected shooting. Now, everything I've read insists I wear both earplugs and muffs while shooting.

I also read that people are using electronic muffs for hunting so they can hear game movement.

If muffs and plugs are necessary to protect our hearing, how is it that electronic muffs, alone, are sufficient?

Thanks.

Also, I have a pair of Howard Leight Impact Sports muffs and wore them yesterday for coyote hunting.

I discharged my 223 and must not have had a good "weld" on my left ear because there was a slight "ringing" after the shot that didn't last long.

I say it didn't last long because it blended in real well with the nonstop "ringing" (tinnitis) I have anyway.

[Greysard]

At over 130dB, there is sufficient time delay in the activation of the electronic hearing protection, to warrant wearing the foam plugs too.

It would be more practical to ask an electronic engineer about that. If the final stage of the amplifier cannot deliver damaging power then no amount of input will change that fact.

Often limiting is done by diodes, alone or in an active circuit. Diodes clamp the signal within nanoseconds. For audio frequencies this means "instantly."

I always use earmuffs; I have an excellent pair of passive earmuffs, very light and with high attenuation. And I have a pair of electronic earmuffs; the attenuation of those is not as good just due to manufacturing. But the amplifier is flawless, and I can hear more in them than without. This is important because you need to know about vehicles and people that are moving nearby.

I never doubled foam plugs and earmuffs. But the loudest calibers I have are .223 and 9mm. Hunting with 9mm is not something I practice often, to great disappointment of the game.

[SWAMPSNIPER]

Huh? What did you say?

[EdReform]

http://www.freerepublic.com/focus/chat/2989447/posts?page=22#22

[RatSlayer]

The only time I always double up is when shooting indoors, otherwise I just use my electronic Peltoirs. Which lets me hear any commands by the range officer.

I also double up if I have the misfortune of getting stuck next to a big magnum rifle with a muzzlebrake on the range. No point in developing a flinch under those circumstances.

I never wear them while hunting because you’ll sweat like a pig in a good fitting pair of muffs with even the lightest exertion. I just except the minor amount of damage a couple of hunting shots a year doles out.

A good fitting pair of muffs or properly inserted foamies are all you really need to protect your hearing. Doubling up is more for just comfort than hearing protection.

[G Larry]

Yes, but that “electrical engineer” would be making poor assumptions about the operation of the ear muffs.

There is a micro-second before the cutoff mechanism is activated.

During that period there are potentially damaging decibel levels.

[LouAvul]

Unless you bought this site, it’s really none of your business, is it?

[LouAvul]

You couldn't be more mistaken. Do some serious research on the subject before you ever shoot again.

The way you actually hear something is that ganglia (small hairs in your inner ear) vibrate from the result of moving air hitting them, transmitting a message to your brain. When the ganglion are assaulted by an extremely loud stimulus (e.g. crash, jet engine, gun shot), they get "pushed down" a little. They never "stand back up" to their full extension. People lose their hearing as they get older as a result of continued assaults upon the ganglion, pushing them down more and more each time. This results in hearing loss, the ganglion are no longer able to effectively transmit a given message. The loss of frequency (pitch) recognition can be segments of the full spectrum, all hertz between low and high.

Facts on noise levels:

1. Decibels measure sound pressure and are logarithmic. That means that only a 3db increase almost doubles sound pressure, a 6db increase quadruples sound pressure, etc.

2. Gradual hearing loss may occur after prolonged exposure to 90 decibels or above.

3. Exposure to 100 decibels for more than 15 minutes can cause hearing loss.

4. Exposure to 110 decibels for more than a minute can cause permanent hearing loss.

5. At 140 dBA noise causes immediate injury to almost any unprotected ear.

6. There is also the more extreme ‘acoustic trauma’, which is an immediate loss of hearing after a sudden, exceptionally loud noise such as an explosion.

Comparative noise levels and length of time exposed to cause permanent damage

Jet engine taking off 140 dB Instant damage

Thunder/Ambulance siren 119 dB 3 minutes Hammer drill 113 dB 15 minutes

Chain saw/Earphones/Concert 110 dB 30 minutes

Bull Dozer 105 dB 1 hour

Tractor/Power tools 96 dB 4 hour

Hairdryer/lawnmower 90 dB 8 hours

Noise levels of firearms:

.22 caliber rifle 130dB

.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.

Properly fitted earplugs or muffs reduce noise 15 to 30 dB. The better earplugs and muffs are approximately equal in sound reductions, although earplugs are better for low frequency noise and earmuffs for high frequency noise.

Using muffs and plugs together: Take the higher of the two and add 5 dB. 30 plug with 20 muff gives an effective NRR of 35.

If you are shooting by yourself, with plugs and muffs on, you get to shoot up to a thousand rounds without damage (louder ammo/gun and the allowable drops by a factor of 5). Shoot with other people and you have to add all the rounds shot cumulatively (10 people shoot 100 rounds and everybody's done for the day; toss a handcannon or 30 cal rifle in and you're back down to 200 rounds cumulative). If you shoot on an indoor range then all the rounds fired while you are on the range go into your total. So you can see that it doesn't take very long on a range to have a thousand rounds popped off around you.

Don't forget about bone conduction of concusive sound waves. The mastoid bone will transmit the sound vibrations directly to your inner ear where the cochela and the hearing nerves resides. Constant exposure to this kind of concusive sound wave, (e.g. 50 BMG, industrial heavy machinery) will result in the degradation of your hearing quality. Even with ear muffs, bone conduction is a big factor in hearing.

[OKSooner]

You didn’t ask, but... don’t ever go to a loud rock ‘n roll concert. I’ve been a shooter all my adult life, and I acquired a case of tinnitus about 10 years ago from loud amplified music.

[WildHighlander57]

Lou,

I have a similar question, but was wondering what people do if they wear hearing aids.
If ear protectors are put on while wearing the aids, the aids squeal ferociously.
If the aids are taken out, the hearing loss is so bad that NOTHING can be heard.
How much amplification do those electronic protection actor’s provide?
I recall taking a handgun class and had to take my aids out in order to use the hearing protectors (not amplified).
With the protectors on, I could hear nothing at all.
The range instructor had to tap me on the shoulder to notify me of anything.
Your info will be greatly appreciated; I am taking my CHL class in a month.

[WildHighlander57]

Not sure how the word ‘actors’ got in my post ; it shouldn’t be in there :0

[jughandle]

I wear earplugs for shooting and at work almost every day and my hearing is still excellent with no ringing. For me, earmuffs get in the way too much.

[Greysard]

There is a micro-second before the cutoff mechanism is activated.

The earmuffs that I happen to have do not operate by creating a counterphase signal. They are much simpler. They consist of:

• Regular earmuffs that provide attenuation
• A microphone and a speaker inside each muff to feed controlled signal levels inside, so that you can hear.

This design does not have a delay, just because there is no cutoff switch and there is no need to process incoming audio in any way beyond clipping it. This is an inherently safe design. I can use them even without turning the amplifier on; then they just act as regular earmuffs. I need the amplifier only to hear external sounds; the amplifier has no effect on suppression of loud noise.

It is theoretically possible to have an active suppression scheme where earmuffs are not really attenuating much, but the speaker generates local audio that is in counterphase to what a nearby microphone receives. This is a very dangerous design - and I don't know of any electronic muffs that use it - because any touch of the microphone will produce a +150..+170 dBa right into your ears, without the ambient signal to counteract. This will be also very sensitive to the disbalance between what the microphone hears and what your ear hears, unless they are colocated (then you must be a cyborg :-)

[LouAvul]

What kind of hearing protectors are you using? Foam plugs that you insert into your ear canal? Or are your hearing aids such that you can’t wear protective muffs either? I have the Howard Leight Impact Sports and with the volume cranked up, I can hear much more than I could otherwise hear. Actually, normal noise levels were really loud.

[rdcbn]

The ringing you are hearing may not be in your ears.

You are probably hearing the sound of the spring operating the recoil buffer of the AR.

It’s right next to your ear and makes an irritating “sproing” type ringing noise after every shot.

[Yardstick]

I abused my ears massively playing loud music in my teens and twenties. Loud amplifiers and hard hitting drummers in small rooms. I don’t know how I managed to avoid hearing damage but somehow I did.

[WildHighlander57]

I had the regular non amplified ones.
But I couldn’t use them.
ALL hearing aids will feedback when the entire ear is covered; no getting around it.
So the aids come out; (no earplugs either)
BUT I am practically deaf without the hearing aids.
Thus my question as to how much amplification the electronic ear protectors provide.
Will they amplify enough so I can hear the range instructor, but attenuate the shooting noise enough so I don’t lose what’s left of my hearing?

[Greysard]

ALL hearing aids will feedback when the entire ear is covered; no getting around it.

I'm not personally familiar with hearing aids; however if I were to design one, I would tie its gain control to the level of the ambient noise that the microphone would normally pick up. If there is no ambient noise (such as under earmuffs, or in a soundproof room) the gain is increased to the point that oscillations begin.

The other option of the designer is to use fixed gain, but then you need to have a way to program that gain into each device individually. They could do that too, for the price that hearing aids command.

But if my AGC theory is correct then a hearing aid *will* work under any electronic earmuff. It will work because it will hear ambient noises - lots of them if you use high gain (not necessary at the range, but quite pleasing in the field.) You will be able to hear range officials; but they often use amplifiers just so the shooters with passive earmuffs, or with foam plugs, can hear them too.

Electronic earmuffs are not expensive, and in worst case you can use them without hearing aids and still hear better because they amplify sounds. That amplification is not comparable to what a custom, prescribed hearing aid can do, but it will be better than nothing.

[Yosemitest]

I'm a retired air traffic controller, 30 years of mostly having an ear piece stuck in one of my ears usually for 2 hours at a time, with a fifteen minute break before another two hours in position.
After I retired out of the military, the Veterans Association told me that the "stick in your ear" speakers are the worst for causing hearing damage.
Get the ones that cover the outside of your ear, or cup your ear and seal to the side of the head, for no damage to the ear canal's hearing hairs.
Tinnitus is no joke. It's a constant ringing in your ears, very similar to the beeping tones you hear during the military's hearing test, and at different pitches, depending on the nerves damaged.

Don't be like me and learn AFTER the damage is done.
Get hearing protection now, and keep it out of your ear canal.

[Celerity]

From what I’ve gathered, two people have warned me about in-the-ear plugs.

I’m not using an electronic ear bud, just a regular stopper. Is this included in the warnings ?

[Yosemitest]

I don't know or I'm not familiar with the "electronic ear bud"
But anything placed inside your ear canal for any length of time is not healthy, according to the retired flight surgeon that did my medical records review for the Non-Commissioned Officers Association prior to my Veterans Administration retirement exam for disability.
The VA doctors also agreed that it does damage and many air traffic controllers develop tinnitus over the years of wearing an ear piece that fits inside the ear.

A regular stopper fits inside the ear canal, so if I were you I'd buy some bulky over the ears cups, commonly called mickey mouse hearing protection.