• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Preventing hearing damage, safe listening levels - CALCULATOR

krott5333

Active Member
Joined
Feb 23, 2021
Messages
121
Likes
166
#1
By trade I am a safety coordinator, so I'm somewhat aware of the dangers of high noise levels. OSHA's limit is 8 hours of exposure to 90db. However, NIOSH recommends an 8 hour exposure of 85 db. I recommend going with the NIOSH recommendation, and that 85db limit will likely be adopted by OSHA at some point in the future as OSHA is often behind the most up-to-date research.

"NIOSH estimates that approximately one in four workers exposed at the 90 dBA OSHA PEL eight hours per day over a 40 year working lifetime will suffer a compensable hearing loss from noise, compared to only about one in twelve workers exposed at the 85 dBA NIOSH REL."

So what about if you're just listening at an hour?

Well, here's a very helpful calculator to give you the TWA, or Time-Weighted Average. https://www.noisemeters.com/apps/exposure-calculator/

Click the standard you wish to use (OSHA's 90db is selected by default, and you can choose the NIOSH or other levels as well).

Type in the sound level, and the exposure time, and it will give you the TWA . You can add multiple listening segments, and it will give you the averaged total at the bottom. (1 hour at 85 db, half hour at 90 db, etc)

A few examples:

1 hour at 95 db is the equivalent of 8 hours at 85 db.
2 hr 30 min at 90 db is the equivalent of 8 hours of 85 db.


By the way, NIOSH has an SPL measuring app for the iPhone, but unfortunately not available on Android (likely because of the inconsistencies of microphone gain from manufacturer to manufacturer).
 

oursmagenta

Active Member
Forum Donor
Joined
Jan 19, 2021
Messages
141
Likes
118
Location
France
#2
I just posted my listening level on another thread, and yours actually give a whole new perspective on this matter (I tend to push the volume up to 80-85 db). I'm bookmarking it !

I'm not saying that like with tobacco (in France for instance) we should advertise with really gross and extreme pictures and/or very menacing warnings the effect of high listening level.

But hey, that's good to know what you risk ...

Especially with good audio gear (the target audience of this forum), with which you can crank-up the volume (because distortion would be well controlled) to a point where you can damage your hearing if done too regularly.
 
OP
K

krott5333

Active Member
Joined
Feb 23, 2021
Messages
121
Likes
166
Thread Starter #3
I just posted my listening level on another thread, and yours actually give a whole new perspective on this matter (I tend to push the volume up to 80-85 db). I'm bookmarking it !

I'm not saying that like with tobacco (in France for instance) we should advertise with really gross and extreme pictures and/or very menacing warnings the effect of high listening level.

But hey, that's good to know what you risk ...

Especially with good audio gear (the target audience of this forum), with which you can crank-up the volume (because distortion would be well controlled) to a point where you can damage your hearing if done too regularly.
Indeed. It's easy to become accustomed to certain volume levels. It's not usually the painfully loud noise that causes the damage, it's the levels that we grow used to that are slowly and gradually harming our hearing. And once those nerve fibers are damaged, there is no reversing it. And we often don't realize the extent of the damage until it's too late, and we find ourselves saying "what" far more often than we should.
 

DonH56

Major Contributor
Technical Expert
Forum Donor
Joined
Mar 15, 2016
Messages
5,023
Likes
8,536
Location
Monument, CO
#4
Again, the OSHA standard (don't know anything about NIOSH) is not meant to target audiophiles, musicians, sound engineers, etc. Their target levels are meant to provide adequate hearing for conversational speech after long exposure over many years. If you want to preserve your hearing, OSHA guidelines should be treated as (far) maximum levels for exposure (volume and duration).

As @krott5333 said, one of the more insidious things is that loud levels deaden our sensitivity so we can listen even longer and louder, but that increases long-term hearing damage.
 

daftcombo

Major Contributor
Forum Donor
Joined
Feb 5, 2019
Messages
2,960
Likes
2,913
#5
Is there a relation between distortion and hearing damage?

Some people I know are very intolerant to distortion (in recordings or in PA systems).

I've been watching old movies with terrible sound: even at very low volumes it seems shouty and fatiguing.


On the other hand, I can think of distortion as something that tells you when it is too loud. If there is absolutely no distortion, there you might pump up the volume and get hearing damage without noticing it.
 

Sancus

Major Contributor
Forum Donor
Joined
Nov 30, 2018
Messages
1,287
Likes
2,879
Location
Canada
#6
These standards are in dBA though. 85dBA is really quite loud, since A-weighting curves frequencies below 1khz down, and those are nearly always the loudest frequencies in music. If you're following 83dBC reference, your average listening levels in dBA will be 5-10 below that for most content, even more for bass heavy stuff.

So unless you listen quite a bit louder than reference, for long periods of time, your hearing is most likely safe.
 

Lambda

Senior Member
Joined
Mar 22, 2020
Messages
422
Likes
220
#7
Would be nice to have a analyzer software that calculates the actual TWA, Dose and LEP,d...
Can't be that hard to implement if you feed is headphone/speaker sensitivity and analog gain.
 

restorer-john

Major Contributor
Joined
Mar 1, 2018
Messages
6,429
Likes
15,962
Location
Gold Coast, Queensland, Australia
#8
I use two calculators for preventing hearing damage. Both scientific of course. Definitely knocks back those SPL numbers with my AKG-702s, but a little uncomfortable for extended listening. Time Weighted Average (TWA) is about 150grams per ear.

calc (1).jpeg


calc (2).jpeg


Thanks for posting. ;)
 
Last edited:

jae

Senior Member
Joined
Dec 2, 2019
Messages
344
Likes
316
#9
Is there a relation between distortion and hearing damage?

Some people I know are very intolerant to distortion (in recordings or in PA systems).

I've been watching old movies with terrible sound: even at very low volumes it seems shouty and fatiguing.

On the other hand, I can think of distortion as something that tells you when it is too loud. If there is absolutely no distortion, there you might pump up the volume and get hearing damage without noticing it.
There are different types of distortion associated with hearing loss, but the amount can vary greatly from person to person. When comparing two people with a similar hearing loss thresholds, one may get significant distortion at a certain SPL while the other may not, or the frequencies at which distortion is most obvious may be different. But regardless the distortions of the recording will add to the distortions associated with the hearing loss, so generally speaking bad recordings will be loss tolerable for these people. There are also pitch deviations associated with hearing loss (especially when the hearing loss is different between ears), distortions and loud volumes may make this effect more obvious and it is fatiguing to experience. The source of the music matters too, as generally people with hearing loss will turn up the volume to accommodate for the frequencies they have lost but it may make the rest of the frequency range too loud or too distorted.

You can think of people with hearing loss as having a crushed dynamic range and sound perception it does not increase as expected with volume increase- generally there will be a point where music seems "too quiet" as they are encumbered by their hearing loss, but then it quickly gets "too loud" within a much smaller dB increase compared to someone with normal hearing. The range at which they can tolerate music or sound in general is much smaller, especially if their hearing loss is is irregular or only present at certain frequencies.
 
Top Bottom