Sound meters can be useful for many different applications and purposes. For me, I wanted one to make it easier to determine whether I should wear hearing protection for a certain tool or not. While there are times when it’s obvious hearing protection is needed, other times it’s not so clear.
Most people know when they should be wearing safety glasses, but it’s a little harder to figure out when you need to wear hearing protection. For instance, is it more important to protect your ears for the hours you are mowing the lawn or the intermittent hammering of your impact driver? Or what’ll cause less long term hearing damage, a ShopVac or a proper dust collector?
According to the National Institute on Deafness and Other Communication Disorders:
Sounds of less than 75 decibels, even after long exposure, are unlikely to cause hearing loss. However, long or repeated exposure to sounds at or above 85 decibels can cause hearing loss. The louder the sound, the shorter the amount of time it takes for NIHL to happen.
DIYers and Pros will often wear hearing protection when working around noise levels that are immediately uncomfortably loud, but even if a sound isn’t loud enough to cause immediate discomfort, it could still be loud enough to potentially cause irreversible hearing damage.
See Also: ToolGuyd Readers’ Favorite Hearing Protection Recommendations
We’re not really good at judging how loud a sound really is, so we need a tool like a sound level meter to measure it for us. I’ve been thinking about buying a meter for a while, and when I was looking for Craftsman tools to test, I found their 82016 Pocket Sound Meter.
We bought this Craftsman sound meter from Sears, at retail pricing.
This sound meter appears to be identical to the Extech SL10, except for the color and printing on the case. The Craftsman sound meter is also occasionally less expensive than the Extech.
The sound meter has a 1/4″-20 threaded insert on the back, so you can mount the meter on a tripod or other fixturing device. It’s powered by a single 9V battery, which is accessed by removing a cover on the back.
It’ll measure sounds in the range of 31.5 Hz to 8 kHz, and has a 125 ms response time, although the display only updates every 0.5 seconds. The meter applies an ‘A’ weighting to the sound measurement, which makes sense for a Craftsman tool, as the ‘A’ weighting is usually used in assessing industrial and environmental noise.
The Craftsman sound meter is contoured to fit in your hand with easy access to both the power and Min/Max buttons. The screen is backlit and the numbers are large and very readable. (You can’t see the backlight in the photo above because I used a flash.)
The meter is simple to use: turn it on and start taking readings. Of course, taking readings that mean something involves more thought. To really take meaningful data, like how loud a tool is, you need to know the distance from the tool, have a repeatable setup, and to be really thorough you should probably note the orientation of the meter.
Also, the manual said you should calibrate the meter before every use, but you either need an expensive calibration device or another calibrated sound meter to compare your readings. There is no way to actually adjust the reading, so all you’d be doing is a Go/No-Go test.
Taking Some Data
I’ve been using my ShopVac for dust collection, and have been thinking about getting a proper dust collector for a long time. It would be nice to have more collection power, but I also thought it would make my shop quieter, as the ShopVac is quite annoyingly loud.
An opportunity to get a dust collector arose recently, just a couple of weeks ago. A neighbor put a practically new Jet 1100CFM dust collector with filter canister out on the curb for free, so I snatched it up.
After I wrangled the behemoth into my shop and got it set up, I turned it on and it sure sounded like it was much quieter than my vacuum, but that’s not what the data I took shows.
To take the data, I set up the sound meter on a tripod at about head level where I would typically stand while working. For these measurements I waited until the reading settled down and rounded the reading to the nearest whole number.
|Table Saw (horiz)||49dBA||77dBA||80dBA|
|Table Saw (vert)||51dBA||80dBA||80dBA|
I was really surprised to see that not only was the dust collector not quieter than the ShopVac, in certain situations it could be louder. Qualitatively, the dust collector seems quieter, but maybe that’s because it emits more of a low frequency rumble compared to the ShopVac’s higher pitched whine.
These sound levels are close to the point where they could cause damage to your hearing, especially considering that a shop vacuum or dust collector will be used with other power tools.
I also tried measuring what the noise level of some of the tools I owned. For this I set the tool on my bench and set the sound meter on a tripod at the same height 3 feet away. Then I clicked the max button until “MAX” showed on the screen. What this does is show the highest db level reached. After a minute or so, I recorded the values below.
|Milwaukee M12 Vacuum||80dBA|
|Ryobi Air Grip while attached||80dBA|
|Milwaukee Impact Wrench||93dBA|
|Milwaukee Right Angle Impact wrench||97dBA|
I was quite surprised at how loud the right angle impact wrench got when I bottomed out a screw. I am definitely wearing hearing protection when I use an impact wrench from now on.
Hearing protection should be used with some of the other tools as well. Tools like the Milwaukee M12 vacuum are in the grey area between “won’t cause hearing damage” and “can cause hearing damage” with prolonged use.
I have no way of checking the calibration, so I can’t report on how accurate the Craftsman sound level meter was. It purports to be accurate within ±3.5dB. The measurements I got made sense from what I know the actual sound level should be.
I also didn’t run a formal repeatability test, but my impression was that the readings were pretty repeatable. If I measured the decibel level of something one day, under the same conditions, the reading was always within a few dB the next day.
One thing that annoyed me during testing was that the meter automatically powers off after 15 minutes of inactivity. In real life usage it probably is a good thing so you don’t drain the battery unnecessarily.
Other than that one annoyance, I found the meter intuitive to use. This probably isn’t the meter to buy if you are trying to comply with safety regulations, but it isn’t bad for somebody who’s interested in doing some noise abatement in their home or shop.
The Craftsman 82016 Pocket Sound Meter is listed at $40 on the website right now, but I’ve found the price seems to fluctuate a bit. Our purchase price was $32 in store.
Buy Now(via Sears)
See Also(Extech equivalent via Amazon)
See Also(Triplett version via Amazon)
Maybe try adding some acoustic ceiling tiles to those cinderblock walls to quiet your shop some and retest?
Several free apps available for smartphone, that work similarly. Save your money, unless you have plenty you want to part with.☺
I have used the free apps in the past and have noticed the results from one app to another can have up to a 10dB margin of error. That’s on the same hardware, which I doubt is calibrated to get the same recording level from phone to phone. I can’t even begin to guess what the variation is between different brand phones.
I just didn’t include a comparison of the sound meter to the apps, since that wasn’t the focus of this review, but it would be an interesting to run a few trials. I’d love to find a calibrated sound source to check against, but it’s not worth it to me or ToolGuyd to pay for one. I wish there was a calibrated SPL noise you could make like how you can test temperature in an ice bath.
There are smartphone flashlight apps and level apps, but neither work as well as real tools. You could also hammer in some nails with your smartphone, so why buy a hammer? =P
Smartphone apps might work in a pinch, but I wouldn’t trust them if the results matter. Have you seen some of the “night vision” and “thermal vision” apps?
I honestly would consider apps that market themselves as “night vision” to be fraudulent or at least border line so. Things like that just prey on users that don’t understand how the phones actually work and don’t realize the limitations of hardware can’t be overcome with an app.
Nice write up.
First off where the smurf do you live that people put out free to the curb JET brand shop equipment.
Secondly there are a number of Apps for your smartphone that are even free in some cases that work fantastically for your purpose. Again as you point out – how accurate is accurate without a known sample to calibrate too.
so using the same non-existent standard – I suspect they are as good or better than the extech or craftsman devices. couple of assumptions – smartphones worth a decent penny need good microphones to use their 2 primary purposes – sound quality of calls and sound quality of recording video. meh.
So if you have a smartphone of decent quality I would suggest trying one out. For relative measurements (which I feel is your goal here) they work fine. And I did simlar to you a few years ago. at what point do I need to have something on.
string trimmer is obvious, blower, table saw. But I also use ear protection with my sawzall, dremel (very high frequency noise is bad too), impact driver and any time I have a hammer in my hand.
Meanwhile – again good write up and on your dust collectors – like a shop compressor – I feel they are best used in some form of closeted or at least baffled space in the shop. IE put up a non structural wall in the corner around the device – lower your apparent DB considerably.
would be a neat comparison to see how close they are.
ones I have used on android – deciBEL, and Smart Tools are the 2 I used the most. Both have charting functions. deciBEL has a frequency center display – IE it tries to tell you the frequency most abundant in that particular sound sample.
Like a proper sound lab meter will do.
Oh other use for your meter – if you haven’t considered it – correcting or calibrating your surround sound system. IE adjusting the levels between all the speakers in a seating location to equate the sound field.
It surprised the smurf out of me too, until now the best thing I’ve ever found out on the curb was a dirty old furnace fan and blower. I see a lot of Ikea-like furniture and old couches that I wouldn’t touch with a ten foot pole though.
I hear about people getting great deals on tools from neighbors, Craiglist, pawn shops, and other sources and I just shake my head, because all I ever find are people trying to sell $500 tools for $550.
The last sound system I bought had a mic for calibrating itself, but that’s not a bad use of one.
Nathan, I understand the desire to put the noise makers in a closet but it’s one of the worst places to put a compressor. At least for the life of the compressor. Many people do just this and wonder “what happened to my compressor?”. Heat and moisture are the enemy of a compressor and in an enclosed space without good ventilation the compressor will run hot as will the output air. Hot air holds more moisture and thus makes it harder to output dry air for your tools, painting and other shop needs. It also usually means more water in your storage tank and more rust.
Good Point I wasn’t trying to suggest boxing the device in completely. Be it a compression or a extractor/vac they need significant air flow and need to have easy ventilation.
Some wall even if open at the ceiling level or whatever – will cut the DB significantly. Mostly because you channel the sound.
I know a guy who built an exclosure out of 2 or 3 layers of window screen around his dust collector. It sits in the corner and he just slides a V shaped frame with a few layers of window screen (at least 2 but I think it is actually 3) about an inch apart and you’d be surprised at how much it deadens the whine. Now that I read this I wonder if it truly reduces the noise that much or just changes the pitch so it sounds quieter. I do know he used the screen so it could ‘breathe’.
My second thought, now that you have the sound meter, would be to take it somewhere like Home Depot during their tool demo days, and (with permission) take readings of the various drills, impact drivers, oscillating tools, etc. Im pretty sure our local HD would let you do that as long as you didn’t disrupt anyone while doing it. In fact, I’d be willing to bet one of the managers I’m acquainted with would want a copy of the results. It would help them better be able to answer customer’s questions about noise levels. It might not be exact, but it would be good enoughnto answer which was quieter.
Enclosure, for some reason it auto corrected to exclosure
The perceived sound level will also be based on the frequency of the sound. Sound at frequencies from (very) roughly 500-6000 Hz will sound louder than sound outside those frequencies at the same dB level.
This graph shows equal loudness contours for all frequencies
And this is the article it came from
You mentioned that the Dust collector could be louder, but your data shows otherwise. Or is the table labeled wrong?
I tried several top rated sound level apps for Android and compared to an annually calibrated sound level meter. All apps needed adjustment by about 2-3 dB on the A-scale. That is actually a significant amount. The frequency response was mostly concentrated in 300-3000Hz region though, which is not good.
One of the issues to be aware of is the microphones used in most phones are optimized for speech frequency range, which is much narrower than the required range for hearing protection.
I am actually surprised that the Sears meter topped out at 8khz. There are often very low and very high frequency components that we do not hear very well but can still contribute to hearing damage and nervous system disorders. That’s why we used to use C-scale for evaluating noise and designating engineering solutions for noise mitigation.
So, apps are perhaps OK to get an idea of how loud something is, but they don’t tell the whole story and are not a serious tool.
I said could be louder, and if you look at the third row on the table( Table Saw Horizontal) The dust collector is 80dB while the vacuum is 77dB.
All in all if you look at the data and the margin for error, you could say they have about the same noise level. I just pointed out that one data point and used it to emphasize that my original guess that it was quieter was spectacularly wrong.
Oops! I missed that one.
In realty, you can reorient the tool itself in different directions ans get different results. It just depends where the the source of noise and what port it’s coming out of. In practical terms, it will change depending where you stand in relation to the tool. Both are louder than the recommended level for hearing protection.
As other suggested, adding some insulation to the hard wall will provide a small reduction in high frequency components. Unfortunately, the materials that will give you the most reduction as more likely to be the best dust collectors!
Good test and review all in all. Thank you.
Aren’t there smartphone apps that measure dB?
Great score on a free dust vac!
Your measurements are useful in that they reflect what your ear will hear in your shop. Of course for proper comparisons with other tools, you’ll need either an anechoic chamber, or a really, really big, quiet, empty field (and matching long extension cord).
I use a common sense approach: If I even suspect that the noise level might be too high, I put on the hearing muffs or insert the ear plugs. Why take the chance of damaging your hearing? You can sustain damage from using a standard rug vacuum, so I wear my hearing protection then, too.
The other problem is, if you’ve already got hearing issues (natural or those caused by years of listening to music at high volume, and/or wearing earbuds ), the damage continues the longer you don’t wear them. At this point, you can no longer discriminate what is or isn’t too loud. And concussive sound levels (think: hunting or trap/target shooting) add to the problem. If you’re using a power saw/drill/shop vac, etc., put them on; it only takes a few moments. It’s as automatic as putting on a seatbelt should be by now. It doesn’t matter if your ears sweat a little; if it will protect your hearing (which is irreplaceable), put them on.
The $30-$40 it costs to purchase this sound meter will buy you a very nice, comfortable pair of hearing muffs that will last for years.
Ben’s not saying that everyone should buy a sound meter to determine whether they should wear hearing protection or not.
I’m also sure he’ll get lots of other random use out of the sound meter.
I have an older pair of earmuffs docked around our household vac for whomever uses it, and always bust out another spare pair for my wife for when she uses the food processor.
Understood. He’s just doing a write-up on the usage and benefits of a new tool in the marketplace, and how well it does its’ job. Playing devil’s advocate, my point was that I feel you should consider buying and wearing hearing muffs ahead of buying a sound meter, whether this model or any other.
We all have to live within a budget, some more so than others. Everyone has a need for hearing protection, though, so that would be a more practical purchase, everything else being equal. That’s just my opinion, and people will choose to do whatever they want to.
Stuart’s right that I don’t think that a sound meter is for everybody, but if you were interested in buying one I was hoping this review would be helpful.
You say you use the common sense approach, but my ears and my common sense were telling me that the Dust Collector was and should be quieter than the vacuum, and I was dead wrong. It really sounds like the vacuum is at least twice as loud as the dust collector (a minimum of 3dB), but for whatever reason they have a similar SPL.
If you are like me where you don’t think about something until you figure it out for yourself, seeing for myself that the Sound Pressure Level from something like an impact wrench is the damaging range is going to motivate me to wear my hearing protection more than any other source. So in that respect it is worth the money to someone like me.
And yes, very much like a IR temp gun, you find all sorts of things to measure when you have one. If for any reason just to satisfy curiosity.
Go figure this post was made today. I volunteered for a d-methionine hearing conservation study only to find that a possible perforated eardrum disqualifies me. We were fitted for ear plugs today (Drill Sergeant School) and a few fellow students were grumbling about how they still won’t wear protection. I’ve had enough sudden loud noises–explosions, gunfire with a muzzle next to the ear, etc–to last a lifetime. This meter seems like a decent buy for stubborn people like me who don’t find everyday noises “loud”.
In my job as a touring concert sound engineer I use a variety of db meters.
The most common set of tools I use are a calibrated reference microphone, a USB microphone interface and a laptop running some type of acoustical analysis software. I use Smaart from Rational Acoutsics. The microphone I use is from a company called Earthworks and is deigned have a flat accurate response. I calibrate it before each use with a device that produces a reference tone at a specific db level. The calibration is made from within the software.
There are a few other variables when measuring db level.
Weighting refers to the sensitivity at which the device measures. A and C weightings are the basic variants. A weighting is the more common and is tailored to reflect how the human ear works at relatively low noise levels. C weighting is flatter and covers a broader range of frequencies including some lower frequencies that A weighting does not cover. Think low frequency rumbles. The choice of weighting will greatly affect your db meters response.
Other variables are response time and averaging. Averaging is particularly useful.
I often use a Radio Shack db meter that I calibrate and compare with my laptop based system. It has a calibration feature which helps to keep it accurate. Something that a lot of inexpensive db meters are lacking. Though sometimes it is hidden inside the case.
Hmmm… I’m going to have to open the case and see if there are any hidden calibration pots. Thanks.
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