Is any old ear protection okay?

[TheHinge]

Or is there some special kind for table saws like a certain decibel rating? Thanks.

[LCHIEN]

quote:Originally posted by TheHinge

Or is there some special kind for table saws like a certain decibel rating? Thanks.

Anything is probably better than nothing.
The less you subject your ear to, the better.
Ear protection is rated in dB (decibels) which is a logarithmic ratio or percentage.

0 dB is no protection at all.
-6 dB or 6 dB attenuation is 1/2 the amplitude.
-12 dB is 1/4 the amplitude and
-18 dB is 1/8 the amplitude
-24 is 1/16th the amplitude.

Most ear protection are around -24 to -28 dB, IIRC.

Sound is rated in dB SPL which is relative to some reference level, can't remember the units, usually pressure.
84 dB or so is the threshold of long term exposure damage IIRC. 104 dB (20 dB more or about 10x amplitude) is painful.

An ear muff with a -25 dB rating will reduce
100 dB SPL signal to 75 dB SPL. Its just addition and subtraction
of the relative levels.

More negative dB rating is better (more sound attenuation) but if its too much you can't hear anything else like machinery beginning to fly apart under stress or your LOYL yelling at you. So don't wear earplugs at -24 dB in combination with ear muffs at -26 dB and get -50 dB, it would be too much.

[Mainemarc]

Loring:

I don't think anyone can touch your comprehensive answer. What LChien said!

[LarryG]

A couple of practical issues in addition to Loring's (excellent as always) scientific stuff:

Hearing protection devices that actually go into the ears, whether loose foam plugs or those stopper-like things with a headband, must be inserted carefully and precisely in order to do much good. This broad type of hearing protection has the advantage of being inexpensive, lightweight, and reasonably comfortable to wear; the tradeoff is that extra time must be taken when inserting them in order to get much benefit. The noise-reduction rating of any hearing protection device always assumes a proper fit, so this element is important.

Muffs are the opposite. They cost more (good sets do, anyway), are very easy to slip on and off, easy to get a good seal that will block out the maximum amount of noise. The tradeoff is that they are bigger and heavier, and can be uncomfortably hot during the summer.

Other issues: some people find that muffs tend to slide off when bending over a workbench; others (like me) dislike the sesnsation of having plugs literally stuffed into their ears.

So it's a personal choice. I prefer muffs, but YMMV.

[monte]

Loring and Larry had excellent answers. As uncomfortable as they are, I've always used the ear muff style.

[Stick]

quote:Originally posted by LCHIEN
More negative dB rating is better (more sound attenuation) but if its too much you can't hear anything else like machinery beginning to fly apart under stress or your LOYL yelling at you. So don't wear earplugs at -24 dB in combination with ear muffs at -26 dB and get -50 dB, it would be too much.

Yep, in a home shop environment, it would be way too much. Where I work, the noise levels in the turbine pits and generator enclosures are over 105dB, so we often "double up" on hearing protection if we're going to be in there for long periods of time. When I was younger and a whole lot dumber, we seldom used any hearing protection. Most older power plant workers have some marked hearing loss. Me, I've got tinnitus bad enough that I can't sleep in a quiet room, it keeps me awake! When my daughters were little I couldn't hear their tiny high pitched voices a lot of the time, and they thought I was mad and yelling at them when I would ask them to repeat what they'd said, often two or three times before i would finally understand it. Protect your hearing. It is precious.

[Tom Miller]

Normally, I prefer the foam ear plugs in situations like trying to read a book in a noisy park, etc.

But for multiple on/off with hands that are full of sawdust, etc., I was a quick convert to the muffs.

Any ol' pair will do, as long as they have a decent dB rating.

Regards,
Tom

[rbfunk]

One minor point with the ear muff style. Make sure that you safety glasses don't interfere with the fit. If the ear pieces make a gap, it defeats their effectiveness.
Bob

[TheHinge]

Well, HD has some for 11.97 that are "20db" so I am guessing it knocks out 20 decibels.

[LCHIEN]

After a side discussion with another member, I looked up some more stuff.
The human ear is funny because of the non-linear response to loudness.
While -6 dB is half as much sound pressure, the ear seems to think
that each -10 dB change appears half as loud.

So a -20 dB reduction would appear to sound 1/4th as loud as the original noise to you.
A -30 dB reduction would seem to be half again quieter.
A -25 dB set of muffs would be somewhere in-between.
Generally the ear can detect differences of 5 dB but 3dB is pushing the limits of your ability to perceive differences.

[germdoc]

I use a set of foam plugs on a headband--easy to take on and off, as I rarely run tools for more than a few minutes at a time. Not quite as good as the earmuff variety, but comfort and convenience count for something.

In my shop class I am always surprised to see WW's--mainly young ones--not wearing hearing protection. I have already lost a fair amount from Led poisoning, not to mention Mr. Tull and Mr. Floyd, so I can't afford to lose any more.

[JR]

quote:Originally posted by germdoc

I have already lost a fair amount from Led poisoning,

took me a second to get it...

BTW - I got a pair of muffs from HF for $2. They work great. And the head-band thingy pivots, so I can easily put on eye protection by pivoting it back behind my neck.

JR