Ear Plugs inside of Ear Muffs - good idea?

[AKElroy]

I double up when at the range due to the folks on either side. When plinking by myself, I generally just use plugs. I was at the range yesterday, and as luck would have it, I had .270's being shot-in on both my right and left.

I go pretty cheap; foam plugs under no-name muffs. They work fine; no ringing at all after 90 minutes on the line.

 

[mikemyers]

I can't say what's best; I just followed the advice in the previous thread about hearing protection. I was all set to buy something fancy, when I got "corrected" by people, saying to check out the NRR rating, and always buy the best you can.

If you're interested in Howard Leight, a page that leads you to comparisons is here:
http://www.howardleight.com/selector

Maybe there are better products, maybe not. I guess after the responses to this new thread, and after my experience today, I will always try to get the best of both ear muffs, and also ear plugs, and wear both of them.

(If electronic ear muffs can meet the same specs now as non-electronic, great... but a year or two ago, the standard ear muffs offered better protection, at least from this one manufacturer.)

 

[drband]

Look for the Howard Leight Impact PRO muffs. My son has a pair. NRR 30 electronic muffs. They are bulky but very comfortable. I don't think you'll find better NRR even spending hundreds more. I saw them on Amazon for under $70. (These are NOT the same as Impact Sport muffs). The Impact Pro muffs are on my wish list!

 

[hso]

We have threads explaining in more detail how hearing protection works that covers the fact that you don't add NRRs for noise attenuation, but a brief explanation might be useful.

Briefly, decibels are logarithmic and each 5dB increment is a doubling of the power of the sound. To illustrate (don't take the numbers for caliber as literal) if you fire a .38 that produces 120dB and then a .357 magnum that produces 130dB the power of the noise that can cause damage didn't go up 130/120 it doubled at 125 and THAT doubled again at 130 (more than 4 times the power of the .38 for noise). Conversely, if you attenuate 5dB the power is halved and if you were to have attenuated 10dB the power would be less than a 1/4 the power of the .357 or the .38 depending.

Since plugs have an attenuation curve that is different than for muffs the don't overlap or combine across all frequencies with the same efficiency. Think of two waves that add together, but because their peaks are offset they don't make one large wave across the same "frequency", but tend to add just a bit. Flip the "wave" to think of the amount of power the plugs and muffs together absorb and you see that together you get something other than double the attenuation. Now consider that human hearing range is 20 Hz to 20,000 Hz and human speech is ranges from 200 Hz to 7,000 Hz we only particularly care about protecting the frequencies in the human speech range. If you look at the chart below you can see that muffs provide more protection at lower speech frequencies and plugs do a better job at higher.


Since dB are logarithmic we shouldn't be too unhappy with having plugs and muffs cut the power of the noise in half that we'd be exposed to with one without the other, should we? And since noise levels are logarithmic it seems foolish to not double up instead of making our hearing take a beating of twice the power we might have prevented.

 

[Doc7]

I double up, hearing normal sound is no problem with my electronic amplified muffs but the sound cut out is much better with the plugs on as well! Shooting my Garand today could hardly hear a muzzle blast at all while being able to carry on a conversation with others.

 

[mikemyers]

(Unless it's already here someplace, and I missed it, I think you should take that single response and make it into a "sticky". I've never seen that kind of information before. If I had, I'd have instantly gotten both better muffs and earplugs.)

 

[Lost Sheep]

So, recommendations on a good value pair? Please share.

See my posts 13 and 14. Particularly 14 near the bottom.

Lost Sheep

 

[EIB0879]

I shoot with earplugs and ear muffs.

 

[AKElroy]

We have threads explaining in more detail how hearing protection works that covers the fact that you don't add NRRs for noise attenuation, but a brief explanation might be useful.

Briefly, decibels are logarithmic and each 5dB increment is a doubling of the power of the sound. To illustrate (don't take the numbers for caliber as literal) if you fire a .38 that produces 120dB and then a .357 magnum that produces 130dB the power of the noise that can cause damage didn't go up 130/120 it doubled at 125 and THAT doubled again at 130 (more than 4 times the power of the .38 for noise). Conversely, if you attenuate 5dB the power is halved and if you were to have attenuated 10dB the power would be less than a 1/4 the power of the .357 or the .38 depending.

Since plugs have an attenuation curve that is different than for muffs the don't overlap or combine across all frequencies with the same efficiency. Think of two waves that add together, but because their peaks are offset they don't make one large wave across the same "frequency", but tend to add just a bit. Flip the "wave" to think of the amount of power the plugs and muffs together absorb and you see that together you get something other than double the attenuation. Now consider that human hearing range is 20 Hz to 20,000 Hz and human speech is ranges from 200 Hz to 7,000 Hz we only particularly care about protecting the frequencies in the human speech range. If you look at the chart below you can see that muffs provide more protection at lower speech frequencies and plugs do a better job at higher.


Since dB are logarithmic we shouldn't be too unhappy with having plugs and muffs cut the power of the noise in half that we'd be exposed to with one without the other, should we? And since noise levels are logarithmic it seems foolish to not double up instead of making our hearing take a beating of twice the power we might have prevented.

Not sure I understood any of this, except that doubling up is good. I have one other observation, that being ears ring when not doubled up, no ring when doubled up.

 

[Drop45]

I also tend to shoot with both, but for a little different reason. Occasionally I like to take the muffs off and wipe my face and ears/muffs of sweat. I cant ask everyone to stop shooting every time I do this so I just double up. And of course I turn my back to the firing line so I don't catch anything in the eyes.

 

[mikemyers]

......I have one other observation, that being ears ring when not doubled up, no ring when doubled up.

I don't know what it's like to shoot with only ear plugs, but if your ears are "ringing" when you shoot with ear muffs, my first thought is that your ear muffs are either too old, or not of the highest quality.

(I also don't really understand that chart, but I can see the advantage of using both ear plugs and ear muffs over using either one by itself.)

 

[kayak-man]

I always double up. I figure I'm exposed to the fire engine and ambulance sirens, chainsaws, and deviant rock and roll enough that I don't want to take any chances.

I also try to position things like the table and concrete pillars between me and the other shooter, because you never know when someone is going to start using a 300 win mag with a muzzle break (then again, I've got a 45-70 guide gun on the way, so I'm not really one to talk)

With the electronic ear muffs, I can still hear range commands and such pretty well

 

[mikemyers]

......decibels are logarithmic and each 5dB increment is a doubling of the power of the sound. To illustrate (don't take the numbers for caliber as literal) if you fire a .38 that produces 120dB and then a .357 magnum that produces 130dB the power of the noise that can cause damage didn't go up 130/120 it doubled at 125 and THAT doubled again at 130 (more than 4 times the power of the .38 for noise). Conversely, if you attenuate 5dB the power is halved and if you were to have attenuated 10dB the power would be less than a 1/4 the power of the .357 or the .38 depending.......

I've read this several times, and I'd like to find out some more specific data. Based on the above information "a .38 that produces 120dB and then a .357 magnum that produces 130dB". Is there a chart somewhere that gives us an idea of the approximate noise level of our different guns, maybe sorted by caliber, for 22, 38, 357, 44special, 44magnum, 45acp, etc? Presumably someone shooting a 22 doesn't need the same protection as someone shooting a 44magnum, except that at a range, the person next to them might have that 44 Magnum...?


In searching for more information, I found this page:

http://www.coopersafety.com/noisereduction.aspx

Lots of explanation there. A small part of the explanation says:

When hearing protection is worn, your level of exposure to noise is based on the NRR rating of the protection device being used. Keep in mind, however, that while the NRR is measured in decibels, the hearing protector being used does not reduce the surrounding decibel level by the exact number of decibels associated with that protector’s NRR. For example, if you are at a rock concert where the level of noise exposure is 100 dB and you are wearing earplugs with an NRR 33dB, your level of exposure would not be reduced to 67 dB. Instead, to determine the actual amount of decibel deduction applied (when decibels are measured dBA which is the most common), you take the NRR number (in dB), subtract seven, and then divide by two. Given the previous example, your noise reduction equation would look like the following: (33-7)/2 = 13. This means that if you are at a rock concert with a level of noise exposure at 100 dB and you are wearing a hearing protector with an NRR 33 dB, your new level of noise exposure is 87 dB. If you are wearing a product with an NRR of 27 it would deduct 10 decibels (27-7/2=10).

.......​

When hearing protectors are worn in combination (i.e. earplugs AND earmuffs), rather than adding the two NRR numbers together, you simply add five more decibels of protection to the device with the higher NRR. For example, using 3M™ E-A-R™ Classic Earplugs (NRR 29) with 3M™ Peltor™ H7 Deluxe Earmuffs (NRR 27) would provide a Noise Reduction Rating of approximately 34 decibels.
​

There's one more number I'd also like to find out - how high a number is too much for safety? Suppose someone is shooting a 1911 with standard 45ACP ammo. I'd like to know how loud it is, but for the sake of discussion, let's say it creates 120 db of noise. Before it's possible to know how much hearing protection is needed, I think we need to know how much noise is too much for our ears.

 

[leadcounsel]

Yes, double up.

 

[ATLDave]

I double up all the time.... I do a fair amount of indoor shooting, so I view it as necessary. I never have problems hearing range commands. It helps to get the electronic muffs that boost noise below 100 db (or whatever the cutoff is) and turn them all the way up.

 

[hso]

Is there a chart somewhere that gives us an idea of the approximate noise level of our different guns

Yep, been posted several times over the years, but here's one for this thread.

Here's Oleg's.



Another


Note that the 140dB "pain threshold" is actually instantaneous damage.
Keep in mind that that is an average of what people experience vs. what you or I may actually experience. You may experience permanent damage at 137 and I might at 143, but on average we're all going to be harmed at or above 140dB (and that's what you see in the charts for many firearms).

Gunfire Noise Level Reference Chart
Below we have listed critical data describing peak sound pressure levels produced by firearms used in shooting and hunting sports. A serious byproduct of this exposure is sensory-neural hearing loss, which cannot be restored to normal. With the introduction of MUZZLE BRAKES and PORTING, the risks of hearing loss dramatically increase. Use this chart as a reference guide for promoting the need of using adequate hearing protection.

Notations
Keep in mind that conversational speech is approximately 60-65 dB, and the threshold of pain is considered to be 140 dB. According to Dr. William Clark, Ph.D. senior research scientist in charge of the NOISE LABORATORY at the Central Institute for the Deaf in St. Louis, the damage caused by one shot from a .357 magnum pistol, which can expose a shooter to 165 dB for 2msec, is equivalent to over 40 hours in a noisy workplace. Dr. Krammer, Ph.D., Ball State University, Muncie, Indiana has documented the following pressure levels.

Table 1. SHOTGUN NOISE DATA (DECIBEL AVERAGES)

.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


Dr. Krammer continues to say that shotgun noise averaged slightly more that 150dB. This is approximately 14dB beyond the threshold of pain, and more than sufficient to cause sudden hearing loss with complications.

Table 2. CENTERFIRE RIFLE DATA

.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
.30-06 in 18 _" barrel 163.2dB
.375 — 18" barrel with muzzle brake 170 dB
Krammer adds that sound pressure levels for the various pistols and ammunition tested yielded an average mean of 157.5 dB, which is greater than those previously shown for shotgun and rifle noise levels. There was also a greater range, from 152.4dB to 164.5dB, representing 12 dB difference, or more than 10 time as much acoustic energy for the top end of the pistol spectrum. It should be noticed that this figure of 164.5 dB approaches the practical limit of impulse noise measurement capability inherent in most modern sound level meters.

Table 3. CENTERFIRE PISTOL DATA

.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 above averages are for all types of ammunition used in these firearms, and should be considered fairly representative. No wonder we hear numerous reports about hearing loss as a result of firearms including acoustic traumas that take hearing completely as a result of one shot. Imagine what the noise levels must be when we incorporate muzzle brakes or porting into firearms, or have a gun explode near the ear due to malfunction.

OUR WARNING IS SIMPLE AND IS IN THE BEST INTERESTS OF EACH SHOOTER. AS THE SOUND PRESSURES INCREASE, SO DOES THE RISK OF PERMANENT HEARING LOSS. IF YOU INCORPORATE A PROCEDURE INTO YOUR SHOOTING THAT INCREASES THE SOUND LEVEL, YOU ALSO INCREASE THE RISK OF HEARING LOSS TO YOURSELF AND POSSIBLY THOSE WHO STAND NEAR YOU. BE SURE TO USE ADEQUATE EAR PROTECTION WHEN USING A FIREARM AND BE CAREFUL OF THOSE NEARBY. LAWSUITS HAVE ALREADY BEEN RECOGNIZED FOR GUNFIRE NOISE THAT HAS RESULTED IN HEARING LOSS. ALWAYS CONSULT A PROFESSIONAL AUDIOLOGIST, OTOLOGIST, OR OTOLARYNGOLOGIST WITH YOUR HEARING PROBLEMS. Hearing loss is not fun and can be prevented.

Compliments of www.earinc.com

 

[ugaarguy]

Is there a chart somewhere that gives us an idea of the approximate noise level of our different guns, maybe sorted by caliber, for 22, 38, 357, 44special, 44magnum, 45acp, etc?

Yes, there is - http://www.freehearingtest.com/hia_gunfirenoise.shtml.

There's one more number I'd also like to find out - how high a number is too much for safety?

140 dB is the threshold for pain. If you experience pain you've incurred permanent and irreversible hearing loss, to some extent. The OSHA legal limit for continuous noise exposure in the work place is 2 hours per day at 100 dB, but NIOSH is far more stringent in recommending that workers should be exposed to no more than 15 minutes of 100 dB sound levels. - Ref: https://www.osha.gov/SLTC/noisehearingconservation/

 

[mikemyers]

The above two responses make me think of someone asking for a handout to buy a cup of coffee, and being treated to a ten course meal! Wow. A goldmine of relevant information. Puts a lot of things into perspective too.

 

[hso]

As long as you can get the instantaneous level below 140 with hearing protection it is difficult to cause permanent hearing damage assuming a rule of thumb that firearms produce 160dB instantaneous for each shot. If you follow the ACGIH and NIOSH recommendations for effective hearing protection reduction you can get below 140 doubling high value plugs and muffs. Keep in mind if you're shooting indoors with many shooters nearby or on a range with several machine guns you may exceed the protection your doubled up hearing pro provides.

 

[old lady new shooter]

(Unless it's already here someplace, and I missed it, I think you should take that single response and make it into a "sticky". I've never seen that kind of information before. If I had, I'd have instantly gotten both better muffs and earplugs.)

I agree, and include the post from the other day with the technical information about the different standards of eye protection.