Highest dB Reduction with Hearing Protection?

I bought the highest rated NNR ear muffs I could get. They are the Browning ear muffs at 37dB. Then I use foam plugs at about 30 dB. From the formulas I found here and on other sites you take the highest rated of the two, subtract 7 and divide by 2. That equals 15. That is the true amount of dB reduction. Then the foam plugs even though they are rated 30, I can only subtract another 5dB. So the most I can get is a 20dB reduction. My equipment is rated by the manufacturer at 110 and 116. They probably go louder, because you can't trust a corporation to be honest about their products.

Is there any way to get more than a 20dB reduction? I will not be using this equipment anymore, but I am wondering can I get a higher protection reduction than the 20dB?

 

After some online searching it seems like that might be the best it can get. Some sites take the NNR rating at its advertised amount, but that has to be wrong. There seems to be agreement about the extra amount the 2nd set give. (Another 5dB reduction.)

 

Are you sure that formula is applicable to earmuffs? The reduction is due to people not using/wearing/inserting ear protection correctly, and earmuffs are pretty simple to use properly.

As I recall when people double up on protection, the basic rule of thumb was the nrr of the earmuffs, plus about another 5 for the earplugs. Maybe it's not correct, but on the other hand, shooting guns at 160db with only 20db of protection would be pretty bad.

This other discussion has a new EPA level label towards the last few posts, where you can see there is a range for the quality of the "insertion/installation."
https://www.tinnitustalk.com/threads/are-foam-earplugs-the-best-plugs-for-concerts.35549/

 

Yes

 

These are garbage. Their dB rating is a false claim. You can find 10 more of the same exact ear muffs under a different brand name on Amazon. The best ones are the 3M Peltor X5A.

 

I did get 2 pair of the 3M Peltors, but the Brownings are a little bit quieter. On the drive home I was checking them on the highway with my radio, and the 3M let more of the radio voice sound through. My car is very noisy and I was cranking the radio to the same volume #. Could you show me some of the ear muffs that are the same? I paid $60 Canadian for the Brownings and the Peltors were under $35.

 

Are you sure that formula is applicable to earmuffs?

From NIOSH, reduce earmuffs NRR by 25%. See source docs etc in discussion below.
www.reddit.com/r/hearing/comments/75egn5/why_do_we_subtract_7_and_divide_2_when/

 

If you want the top noise reduction, then you need to start with a top earplug. The best ones have a NRR 33 rating, and you mentioned NRR30 ones.

 

(33-7) x .5 = 13dB
(30 -7) x .5 = 11.5dB
Difference in dB between the two is 1.5dB

But it doesn't matter. The when using 2 sets of plugs, you take the highest pair, and do the formula. The most you can subtract for the 2nd pair is 5dB.

The most you can possibly reduce the dB is 20dB. That is with the 37dB ear muffs and whatever foam plugs at 5dB for the 2nd set.

I will make a point to find the best foam plugs. I am just guessing at 30 for the ones I have. They could be 32 or 33dB ones.

 

Have you seen

 

I don't know, but I think I will use the lowest reduction, because I used 37dB muffs with a pair of quality foam plugs at about 32dB. I ran my Stihl brush trimmer for about 30 minutes and I probably won't recover. Stihl claims the trimmer is at 110dB. If I was getting the anything close to the numbers the plugs are rated at there should be no problem.

I will add I thought the trimmer was at 100dB, not 110. My mistake for not digging around and finding the dB of the tool I was using. I am selling my chainsaw, my brush trimmer, and my wood splitter.

 

You will be able to know whether or not you will recover only about a month after the event. Temporary spikes can last longer than three months, and most begin to fade after a month. Right now it is reasonable to assume that your spike is temporary.

I believe that one shouldn't think too much about those dB ratings. You could use trial and error to get a sense of what is and what isn't safe for you and act accordingly...

 

There is a good chance that after 2 years or so you will become more resilient (although just because a sound doesn't produce an immediate spike doesn't mean that it is completely safe - personally I plan to not push the boundaries). It makes sense to avoid all noise exposures that you can easily avoid (get other people to use those tools).

 

With my new knowledge about noise and hearing protection I am not feeling good about hiring others when I know they are going to hurt themselves toiling for me. I did find someone to do it, but I don't feel good about it.

I did some research and there is a corded electric chainsaw that is as powerful as the gas units. My Stihl is rated at 116dB, and the electric Stihl is 96B. that's a good start, a 20dB reduction. With double plugs the running dB could be 76dB. I will not be doing this work though. Too much risk.

 

Good point. I think that a healthy person wearing hearing protection ought to be ok, but of course there is no way of knowing just how much noise exposure that person had had, and how healthy they really are.

 

And they were the X5A?

here are others of the same ear muffs under a different brand name

https://www.amazon.com/ClearArmor-141001-Shooters-Protection-Folding-Padded/dp/B00NKSMPZW/
https://www.amazon.com/dp/B06XMY7KC2/
https://www.amazon.com/Tvoip-35dB-Highest-Safety-Muffs/dp/B07GPGH5PP/
https://www.amazon.com/Silence-industrial-shooting-protection-Lightweight/dp/B018F4FS72/
https://www.amazon.com/gp/product/B07H2LCZXH/
https://www.amazon.com/Browning-12699-Hearing-Protector-HDR/

 

Yes brand new 3M X5A.

Thanks for looking up those muff links for me. I will return the Brownings and get a pair cheap.

 

Most of the ear muffs you listed here are not 37dB reduction.
I did return the Brownings but I think maybe I should have kept them?

 

Yes, too bad you returned them, as then you would be able try both muffs at the same time. You would most likely conclude that X5A muffs are more comfortable and provide similar or more protection. X5A state that their noise reduction is 29 dB. This might imply that some of the other brands are inflating their noise reduction rating.

 

The X5s I bought are 31dB NNR. I did try them both at the same time. The Peltors are way more comfortable, but the Brownings did cut more sound. I drove with them for 1 hour switching back and forth in my noisy car with the radio on. The radio is digital so I could turn the volume down and then back up to the same number. The Brownings cut the radio voices more than the Peltor X5 did. The Brownings were not nearly as comfortable as the X5s though. I think the Brownings may have cut a bit more of the bass as well.

 

Forget the numbers, they are BS and inflated anyways. Look at the design. They are identical. And are all from the same source, just with a different branding.

 

I ordered these you linked to.
https://www.amazon.com/dp/B06XMY7KC2/?tag=tinntalk-20

They do look the same, although the headband is different. they cost $30 CAD with shipping and exchange. The Brownings were $73 CAD locally with tax.

I will see how they are. Thanks!

 

So I bought the Stihl battery line trimmer with 3 attachments. It cost me $2500 for the options I got. Well worth it as it is quiet. But uncomfortable to use as the battery is 18 pounds and is a backpack.

 

This whole thing is so confusing.

I think, like it was said, that the reduction in NRR is from people not using hearing protection correctly so they have to include that in the OSHA NRR calculation. In the lab setting where it is perfect the NRR is exactly what it is advertised. In the real world where people don’t put in ear plugs correctly, they are lowered. This makes sense that people don’t wear it correctly so they have to take that into account.

If someone were to wear the hearing protection correctly, I feel it would be closer to the advertised NRR. Not perfectly, but a lot closer than this (X-7) * .5 bullshit.

 

110-115 is probably where some of the loudest equipment I have runs at muffler level -- noise at the operator's ear level is likely to be reduced by a factor of 2-4 at least (remember, 6db reduction is 50% reduction in noise energy; 10db reduction is 50% reduction in subjective volume, or something. So, 115 at muffler might be more like 95-103 at operator ear level).

I jam orange foamies in, slam shooters muffs over them, and go nuts on the lawn. It's super hard on my knees and shoulders because of the 16hp beast I manage, but it's only hard on my ears when I get it stuck in miud so badly that I start shrieking and howling in animal rage as I go compile a stack of scrap wood to get myself out

 

Can you link to exactly what the heck you bought? That sounds very high; as far as I can tell, Stihl's most powerful battery line trimmer is the FSA 130R, and I see that here, with the really expensive battery pack, for $1500: http://gardenlanddirect.com/stihl-fsa-130-r-battery-powered-line-trimmer/

Also, can I ask how much acreage you're managing, and what's on it? Only asking because I have 11 acres including some really gnarly, steep ATV trails, lots of garden space and LOTS of hedge lines/etc which I have been maintaining for 2 years with a $100 40v Black & Decker cheapo consumer thing.

I see the main advantage of the AR-3000 battery pack is a 240min run time at max power; I am guessing you require that? Sounds like whatever you're doing it's a hell of a lot more ambitious than what I do -- is this your full time job? Keeping on top of a job, a family, and 11 acres is just about all I can manage and still have time to hang out with my family, be a good dad, and have some free time.

I get about 40 minutes runtime out of my little B&D with 2 batteries; this is fine, but my use case is that I go spend my lunches outside with trimmers and chainsaws, so it's not more than a 1-2 hr/day deal for me

 

I bought the Ar-3000 battery, the 130 combi head, the best charger, the blade attachment, the string attachment and the little pruning chainsaw attachment. $2500 includes 13% taxes.

I have 200 acres.

 

I can't even imagine. Active farm?

Got any maple trees?

You've got me dreaming about that line trimmer even though it's SUPER overkill for my needs.

Got any recommendations for a good civilian-plus-grade tractor & loader combo that I can get used for under $15,000? (serious question. Have been advised to look at John Deere stuff prior to some specific year when they started doing all the crazy DRM bullshit).

One use case is hauling wood out of fairly steep woods so I am looking for something on the smaller side, and I'm open to the idea that a side-by-side ATV is gonna meet my needs better than a tractor.

 

The trimmer is not as powerful as my FS 240 line trimmer. But it says it is 110 dB. The new one is around 92. It is nice and quiet with 2 sets of earplugs. If I could I would return the AR3000 for the AR1000 battery pack. The 1000 is 6 pounds lighter. The AR3000 weighs in at 18 pounds. Too heavy for me I have come to find out. So the extra battery power is mute as I can't physically weed whack for anywhere long enough to use up the extra power.
I don't know anything about equipment. We have a 1973 David Brown 995 my father bought new in 1973. The land is lightly farmed by a local farmer. WE don't allow Monsanto or any pestisides, GMO or coated seeds. We have a small 20-30 hive beeyard.