ETS EC noise levels?

[AlexThePalex]

Finally, please share your documentation of why you are convinced using the ROS I tested can damage hearing when used in a normal manner ie not holding it against your ears.

What exactly is a normal manner? Because I think you completely misinterpret how test results translate to using a sander in practice.

During work, you move the sander around in many different position, nobody only works with a sander at arms length on a table. Many times when people use a sander, or any other power tool, the tool comes very close to the head and then noise levels increase beyond the safe limit. How exactly do you sand a vertical surface of a house when you stand on a ladder? Where's your "safe" distance? And what exactly is the influence of the surface you work on on the sound level? Put your sander on a cabinet and you've got this whole sound box vibrating with your tool, amplifying it like a guitar amplifies its strings.

Furthermore, it's nonsense to just say there's ONE limit of 80 decibel because your hearing is not consistent over the entire range of frequencies, the extremities on the high (20.000 hz) and low (20 hz) end will be damaged much quicker than the middle. Different frequencies carry a different amount of energy.

As for documentation, anybody in the industry, be it tool manufacturers or safety regulators, recommend using hearing protection with power tools, all the time. They do not recommend this because they want you to look cool.

Besides that, maybe you should think about how those safety regulations work exactly. They are not meant to protect you 100% absolutely, because in that case any safety regulator and sound researcher would advice you to stay away from loud noises at all time.

Your hearing has evolved over millions of years, and nature simply doesn't work on a 80 decibel/8 hours per day exposure basis, only human machine parks do, which only came to life in the last 200 years. Maybe you don't realise this if you grew up in an urban environment, but nature is actually very quiet out there, and your hearing is optimally tuned to function in such an environment, listening to the minute sound a prey or predator might make, and not an environment with machines blasting in your ears 8 hours a day.

Those rules are meant to find a BALANCE between the necessity of noisy production sites and people's long term safety. Right now noisy production environments are an economic necessity because that's just how machines work, they do good stuff but they make a heck of a lot noise, which is not good. You can't get rid of them because that would mean going back to the stone age. So we have to find a level where we can still operate those machines without losing hearing right away. That doesn't mean you're 100% safe over the long term and can simply do anything you want.

 

[Huxleywood]

Finally, please share your documentation of why you are convinced using the ROS I tested can damage hearing when used in a normal manner ie not holding it against your ears.

What exactly is a normal manner? Because I think you completely misinterpret how test results translate to using a sander in practice.

During work, you move the sander around in many different position, nobody only works with a sander at arms length on a table. Many times when people use a sander, or any other power tool, the tool comes very close to the head and then noise levels increase beyond the safe limit. How exactly do you sand a vertical surface of a house when you stand on a ladder? Where's your "safe" distance? And what exactly is the influence of the surface you work on on the sound level? Put your sander on a cabinet and you've got this whole sound box vibrating with your tool, amplifying it like a guitar amplifies its strings.

Furthermore, it's nonsense to just say there's ONE limit of 80 decibel because your hearing is not consistent over the entire range of frequencies, the extremities on the high (20.000 hz) and low (20 hz) end will be damaged much quicker than the middle. Different frequencies carry a different amount of energy.

As for documentation, anybody in the industry, be it tool manufacturers or safety regulators, recommend using hearing protection with power tools, all the time. They do not recommend this because they want you to look cool.

Besides that, maybe you should think about how those safety regulations work exactly. They are not meant to protect you 100% absolutely, because in that case any safety regulator and sound researcher would advice you to stay away from loud noises at all time.

Your hearing has evolved over millions of years, and nature simply doesn't work on a 80 decibel/8 hours per day exposure basis, only human machine parks do, which only came to life in the last 200 years. Maybe you don't realise this if you grew up in an urban environment, but nature is actually very quiet out there, and your hearing is optimally tuned to function in such an environment, listening to the minute sound a prey or predator might make, and not an environment with machines blasting in your ears 8 hours a day.

Those rules are meant to find a BALANCE between the necessity of noisy production sites and people's long term safety. Right now noisy production environments are an economic necessity because that's just how machines work, they do good stuff but they make a heck of a lot noise, which is not good. You can't get rid of them because that would mean going back to the stone age. So we have to find a level where we can still operate those machines without losing hearing right away. That doesn't mean you're 100% safe over the long term and can simply do anything you want.

My testing was simple but designed to produce higher SPLs than standard OSHA or NIOSH testing partly to make the testing easy for me and also quite repeatable if I wanted to come back and test a different tool and have the numbers be relatable.  I tested both in slow and fast response as well as determining the maxima and to go over the OSHA standards you would have to have the sander VERY close to your ears for hours on end.  I acknowledge background and secondary noise can be an issue but for the ETS EC to even hit the OSHA PEL requiring hearing protection for 8 hours of exposure per day the acoustic energy would have to be 16 TIMES what the ETS EC was emitting while I was testing it in use in a pi/2 steradians environment. 

If you have some testing of all the potential scenarios please publish them, if you do not you are simply guessing, the issue here is I am doing testing (and understand how to do it and have the equipment to do it accurately) and the numbers simply do not bear out what thus far is simply your "gut" feeling.

"Furthermore, it's nonsense to just say there's ONE limit of 80 decibel because your hearing is not consistent over the entire range of frequencies, the extremities on the high (20.000 hz) and low (20 hz) end will be damaged much quicker than the middle. Different frequencies carry a different amount of energy."

The ear is not equally sensitive to all frequencies that is the reason for the discussion of weighting with regards to the SPL meter and my tests were done using the same slow graphing and A weighting that OSHA and NIOSH tests are done with this takes all the guess work out of the equation.  Obviously different frequencies of sound have different energy levels for the same amplitude.  High frequencies have been shown to cause more damage than low frequencies, again I did not do a spectrum analysis but my ears are pretty good from years of playing instruments and voicing speakers and none of these sanders have much amplitude in the high frequencies and the ETS EC has less than the others.  The Deros and ETC EC both have a little sizzle in the 8-10k Hz range most likely bearing noise but it is significantly lower in amplitude than the octave between 3k and 6k Hz and the ETS EC has a good bit down to maybe 1.5k Hz.  None of the sanders exhibited enough high-frequency content to be concerning.  Low frequency sound (not really an issue here as it is all in the midrange) is a current topic of research particularly infra-sonic sound for years it was not considered an issue but it MAY be.  Stepping aside from ultra high level (120 dB) infra-sonic (under 20Hz and most research now is looking at ULF

 

[AlexThePalex]

but I prefer to measure and use accepted science and industry standards to make my choices. 

The industry standard is to wear hearing protection.

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That actually sound like something one of my fair weather "explorer" friends might say.  Come with me and spend a few nights in the jungles of Central America during the rainy season and see what you think about nature being quiet, then hen the rain ends and you think you are in for an audio respite the critters start talking... try a wind swept valley or camp near a spring thaw stream.  Nature is far from quiet all the time and often VERY loud for long periods of time often in the exact areas people would have lived deep in the past.  Human hearing has evolved to be most sensitive in the range of human speech vs any direct relationship of predator/prey development.

You only describe exceptional places and circumstances. Odd how the exceptional can be used for your reasoning but has no place in mine.

Oh, and people's first reaction to those circumstances is too hide away. Nobody is going to run around in the night in the rainy rain forrest for 8 hours and call it just another day at the office.

 

[Holmz]

Well the DEROS and the ETS/EC seem quieter than older school sanders, so I think they are quieter.

I usually use 15 dB attenuators from etymotics or foam jobs that are ~30dB, but if it is only a minute then I may forego the ear plugs.

 

[Michael Kellough]

I hate dust and noise but using hand tools exclusively is too slow so I bought into the Festool system.

I'm very glad to no longer need to wear a dust mask but I still wear hearing protection even when simply vacuuming, if the ear muffs are close at hand.