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Are your ears really protected? Find out with NIOSH’s QuickFitWeb

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Approximately 30 million workers are exposed to hazardous noise on the job. While we would prefer to eliminate noise through engineering controls or reduce exposure to noise through administrative controls, hearing protectors are critical when noise is unavoidable. 

Hearing protectors only work if they fit your ears and you wear them properly.  An earplug that doesn’t quite fill your ear canal or an earmuff with a small crack in the padding will let lots of noise into the ears through any gaps, even tiny ones.

To help you get the most from your hearing protectors, researchers at the National Institute for Occupational Safety and Health’s (NIOSH) Pittsburgh Research Laboratory developed QuickFitWeb, an online tool to check your hearing protection in a minute or less.

Poor Fit = Poor Protection

Studies of hearing protector users have shown repeatedly that average protection values in the real world are much lower than the labeled Noise Reduction Ratings (NRR) determined in laboratories with trained and motivated subjects. Even worse, many hearing protector users get virtually no protection at all because of poor fit. It’s hard to tell if your hearing protectors are working well just by looking at them. A more accurate approach is to check how much they block or “attenuate” noise. Hearing protectors vary in their attenuation characteristics, with most providing a maximum of 20 to 35 decibels of noise reduction when worn correctly. Any hearing protector that’s suitable for use in noisy settings will attenuate noise by at least 15 decibels.

How QuickFitWeb Checks Hearing Protectors

The NIOSH QuickFitWeb helps you determine if your hearing protection is giving you at least 15 decibels of attenuation by comparing two “threshold” tests—one without hearing protection and one with the devices on or in your ears. To use QuickFitWeb, play the test sound (a pulsing random noise that sounds like “wooshing” to most people) from the website. As you listen to the sound, adjust the volume on your computer until the sound is right on the edge between audible and too quiet to hear. That sound level is your “threshold of hearing.” Then put on your hearing protectors and play the next test sound. The second sound is exactly the same as the first except that it’s 15 decibels louder. If you can hear the louder sound through your hearing protection, the devices are attenuating sound by less than 15 decibels and are not protecting you adequately. You need to correct the problem by trying hearing protectors that fit you better or correcting the way you put them on. Then you can try the test again until you get a good fit.

Under the Hood

The QuickFitWeb is a highly simplified variation of standard hearing protector evaluations. The QuickFitWeb tests only one octave band centered at 1000 Hz. That is, we filtered a sample of random noise to have maximum energy at 1000 Hz and with energy dropping to zero at 500 Hz and 2000 Hz. Using just a single test frequency saves time and serves the purpose of checking for adequate fit since well-fit hearing protectors will have good attenuation on all frequencies. The QuickFitWeb also streamlines testing by checking for just one attenuation value: 15 decibels. If a protector is poorly fitted, it will usually provide far less than 15 decibels of attenuation. Protectors suitable for noisy environments are generally rated to provide at least 20 decibels of attenuation so they should completely block a sound that’s just 15 decibels over the user’s hearing threshold.

Related Developments

quickfit testerQuickFitWeb is a spinoff from the NIOSH QuickFit standalone device. QuickFit is a small, self-contained device that looks like one side of a set of earmuffs and allows the user to play test sounds, adjust the threshold,and check for at least 15 decibels of protection. It was designed to use inexpensive off-the-shelf circuits and parts so that it could be produced at very low cost. Ideally, it could be placed affordably near any noisy worksite so workers could check their earplugs every time they put them in. Prototypes of the QuickFit device started a series of field evaluations in February 2008.

Another related product is QuickFitMP3—a set of digital sound files in the popular MP3 format that can be played on almost any computer or music player. By playing the sounds in sequence, users can test whether their hearing protectors are attenuating noise by at least 15 decibels. These MP3 files are downloadable now from the QuickFitWeb page. A future enhancement of this approach will be to provide a sequence of MP3 “tracks” that vary by 5 decibels to allow users to assess approximately how much attenuation they are getting from their hearing protectors. They will also use the separation possible with stereo headphones to permit testing earplugs inserted in right versus left ears independently. These added sound files will allow some additional training and evaluation scenarios that are beyond the scope of the current QuickFit products.

Noise-induced hearing loss is 100 percent preventable but once acquired it is permanent and life-altering.  The QuickFit products are tool for workers to ensure that their hearing protection is actually working and preventing hearing loss. 

—Robert F. Randolph, M.S.
The author is the Manager of the Hearing Interventions Team at NIOSH’s Pittsburgh Research Laboratory

More information on work-related hearing loss is available on the Noise and Hearing Loss Prevention page on the NIOSH website.

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24 comments on “Are your ears really protected? Find out with NIOSH’s QuickFitWeb”

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    Maybe I missed it, but I didn’t see any recommendations regarding left right handedness. I for instance know that I hear better in one ear then the other. This may not be a factor when testing with headphones but could affect the outcome in other instances. In all though I think it is an invaluable tool

    You’re not alone—many people have better hearing on one side, which can complicate testing hearing protector fit. When asymmetrical hearing ability is combined with a loudspeaker fit testing setup, the results will primarily reflect protection levels for the “better” ear. That’s because the “worse” ear won’t hear the test sounds as well. Ideally, each ear should be tested independently from the other, but that may be virtually impossible when listening to diffuse sound through loudspeakers. If you know or suspect that your ears have different sensitivities to sound, we recommend that you use a good set of around-the-ear headphones to perform the test. To test each ear independently with headphones, use the balance control on your system to send all of the sound to one side at a time. If you want to stick with loudspeakers, you can still isolate the ears somewhat. To do this, we suggest testing your “better” ear first. After you do the test once with your best ear, isolate that ear from sound by inserting an earplug into it, and consider putting one side of an earmuff over it to get even more isolation. Then, you can go ahead with a test of the “worse” ear.

    The instructions don’t yet specifically address the situation of asymmetrical hearing ability coupled with loudspeaker testing because we were trying to keep the procedure as quick and simple as possible. However, the situation is very plausible and some users could benefit from information on recommended ways to test each ear separately. We’ll incorporate this excellent suggestion into the the process of updating and improving QuickFitWeb.

    Can the computer make a difference? I’ve tried this with 3 different types of plugs and even though I believe that I have a good fit, I still hear the “with hearing protection” sound. I’ve been using hearing protection and instructing others on proper selection, insertion and fit for 32 years, so I’m pretty confident that I have a good fit.

    The computer used for QuickFitWeb can certainly make a difference under some conditions, although we have tried to minimize the number of things that can go wrong. To confirm the validity of QuickFitWeb’s test sounds, we’ve measured its output through several typical headphones and speakers connected to different desktop and laptop computers. However, it’s not feasible for us to test every possible combination of computers, sound systems, and software. In your case, I would look first at the overall volume level on your computer. QuickFitWeb works best when the quietest “threshold” sound you can hear occurs when its volume control slider is somewhere near the center. You probably have software volume controls on your computer and possibly also on your speakers or headphones. Try adjusting the system and speaker volume controls until the QuickFitWeb sound is just barely audible when its slider is in the middle. Then, use the QuickFitWeb volume slider control to find your threshold of hearing. If you are using loudspeakers, you may also want to switch to headphones for the test to minimize the effects of background noise. A less likely possibility is that a driver or other software component is performing compression or automatic volume adjustments that are interfering with QuickFitWeb. If you still seem to be getting unexpected results, I will be happy to correspond with you offline about your specific setup.

    Interesting approach for those with regular internet access—likely not suitable for people with any significant amount of hearing loss, since getting enough gain from the unoccluded series could be tough. The assumption of 15 dB as a sufficient protected level could be problematic as well—I just did a project at a metal can plant where exposures of 100 to 105 were pretty common. It could be an issue of this test indicating a worker is sufficiently protected when in fact they are not. Of course, there is the fundamental question of objective vs subjective approaches—the threshold setting/threshold response issue can be difficult to address. Having this technology in a hand-held could be a good idea, as it simplifies delivery.

    Mr. Hager raises some good points that will help clarify the uses and limitations of QuickFit and QuickFitWeb. Our design objective was to give hearing protector users a way to check the fit as quickly and simply as possible. While simplification sometimes forced us to make hard decisions about which capabilities to keep and which to eliminate, we tried to preserve as much everyday usefulness for as many users as we could. For instance, as Mr. Hager points out, users who have a significant hearing loss may have difficulty adjusting the QuickFit loud enough to reach their hearing threshold. Our goal with the standalone QuickFit is to reach hearing thresholds of 60-65 decibels (dB) at 1000 Hz, which should accommodate most users—even those with substantial noise-induced hearing loss in the 4000-6000 Hz range. Those users who have hearing that approaches or exceeds the limits of QuickFit would probably benefit from an individualized consultation with an audiologist or physician.

    QuickFit relies on a subjective Real-Ear Attenuation at Threshold (REAT) technique because it is simpler than an objective Microphone In Real Ear (MIRE) technique. Moreover, REAT doesn’t require special earplugs or in-ear microphones. On the other hand, MIRE can be more accurate and reliable than REAT, so periodic MIRE fit assessments could be used to complement more frequent checks with QuickFit.

    Our choice of a 15 dB attenuation value also deserves some clarification. We wanted to test just one attenuation level because it takes much less time than testing a range of attenuation levels. We picked 15 dB because all users of standard hearing protectors should get more than 15 dB of protection (excluding some musicians and other specialties where sometimes 10 dB or so is ideal). How much more than 15 dB is ideal for a particular individual depends on their noise environment and what sounds they still need to hear “through” their hearing protectors. QuickFit is intended to “catch” poorly fitted hearing protectors, but we agree that a more extensive assessment is appropriate for individuals who need an especially high degree of protection because they are exposed to extremely high noise levels or for other safety considerations.

    QuickFit can never replace or eliminate personal attention from hearing professionals using more sophisticated fit testing systems. However, as Mr. Hager points out, it can be used to simplify delivery of fit testing so that it is more readily available when and where protection is needed most.

    I am a graduate student at Old Dominion University and I am also an active duty Navy Chief Hospital Corpsman with extensive background in hearing loss prevention. I think that this device would be an invaluable asset when fitting members for hearing protection. I have found that when fitting members for hearing protection it is mostly for comfort and that does not correlate to good protection all the time. Have there been any epidemiological studies that show the advantages of using this device in addition to the normal comfort fit. How many organizations do you know that are using this product on a consistent basis to ensure proper protections? Have there been any studies to examine end users who were fitted for hearing protection using the comfort-size fitting method alone and then re-fitted using this device to see if there was any need to change protection size or type. It is also import for use to emphasize how quickly noise can produce a threshold shift and this device and also be used to show the end user how much noise the protection in preventing, and that might help them to wear their protection.

    I agree that it’s important to have evidence supporting the benefits and acceptance of the QuickFit technologies.

    A number of studies have shown that the general approach of individual fit testing for hearing protectors is an effective technique for improving hearing protector attenuation. These findings have prompted the National Hearing Conservation Association’s NHCA-OSHA-NIOSH Alliance to endorse individual fit testing as a “best practice.” QuickFitWeb and the QuickFit device incorporate key aspects of the recommended individual fit testing techniques, so we expect them to show similar benefits. We have completed acoustic testing of the NIOSH technologies, but we are just beginning the process of conducting tests of attenuation levels with potential users. We are looking for partner organizations to assist us with access to field sites and workers who can help us evaluate the performance of the QuickFit technologies.

    The QuickFit is brand new and not yet in production, so it’s not yet in widespread use in organizations. We are actively looking for development and manufacturing partners to take the technology and produce it in large quantities. As that happens, we plan to track dissemination and use of the device.

    Further evaluation testing and dissemination are activities scheduled in a NIOSH Pittsburgh Research Laboratory project for the coming year. As soon as these activities are completed, the results will be published and made available on the NIOSH website.

    You make a good final point about training users about preventing temporary threshold shifts (TTS) through use of hearing protection. We will be sure to include information about the TTS danger signs in the training materials we are preparing to support QuickFit users.

    When taking your quickfitweb test I found there is a fine line on my computer between barely audible and off. Is it still a valid test to leave the volume one setting above off and just compare sound sample 1 (without earplugs) and then with earplugs in compare sound sample 2. If sample 2 is louder then sample 1 you failed to achieve 15 db of protection?

    The QuickFit device assess hearing plug effectiveness on a by ear basis. When using the software and playing the mp3 files over speakers is it as valid when assessing both ears concurrently. This would seem so as the +15db is presented bilaterally.

    You are right in observing that the loudspeaker version of the test involves both ears at once. In most cases, it will tell you if both ears are protected to the 15 dB level. For instance, if you have one ear well-protected with an earplug but the other is poorly protected because of a poor fit, you will hear the test sound through the poorly protected ear. Because of the way your ears and brain process sound, it may be difficult to tell which ear is better protected. In that case, you can perform the test with headphones and use the balance control on your sound system to send most of the sound to one ear at a time. The headphones should be the large “circumaural” type that surround the ear and have a cushion that fits the side of your head to keep external sounds out. The headphones should have plenty of space inside the earcup to avoid pressing on the external ear or earplug. We recommend testing each ear separately if the user has a large difference in hearing ability from one ear to the other, or if fitting one ear with an earplug more difficult than the other because of a different ear canal shape or other factors.

    Unfortunately, earplugs with a noise reduction rating of 33 often provide less than 15 dB of protection in practice. The most likely reasons are that the plugs do not fit well or are not correctly inserted. We suggest trying the test again with a different type of earplug, or practice the correct insertion steps to see if you can obtain a better fit.

    Others have suggested adding tests for more attenuation levels besides 15 dB to provide more feedback about the actual attenuation an earplug user has accomplished. Doing so would add a small amount of complexity to the test, but it is otherwise feasible and we have developers working on a version that includes stepped attenuation levels. A test for 10 dB attenuation would have limited value because that’s not enough protection for most noisy settings.

    Derating schemes are intended to approximate the lower attenuation levels actual earplug users obtain. However, fit testing with the QuickFit or other testing systems provides actual attenuation information, so no derating assumptions are needed. Frequency weighting is also irrelevant to testing with the QuickFit. The system uses a single test band of 1000 Hz, which is unaffected by A-weighting, C-weighting or any other commonly-used frequency weighting function. The attenuation value can be used as-is without adjustment.

    We have not formally evaluated the HINT test, so we cannot provide any official view about it. We encourage anyone who has concerns about their hearing to make use of online resources, then follow up with an audiometric assessment with a qualified audiologist or ear-nose-throat doctor.

    The volume level on your computer’s sound system also affects the sound generated by the QuickFitWeb test. In some cases, it may be difficult to adjust the QuickFitWeb threshold sound level so that the sound is just audible without first adjusting the sound on your system. When that happens, we suggest setting the QuickFitWeb volume control to the center or just below, then adjust the volume on your computer (using the speaker volume control or software volume control) until the test sound is barely audible. Then you can use the QuickFitWeb volume control for fine adjustments.

    In the case you describe, you can still get a useful test if sound 1 is audible without earplugs and sound 2 is inaudible with earplugs. In this situation, the protection from your earplugs is probably greater than 15 dB because the starting point for the first sound is already higher than your hearing threshold. For instance, if sound 1 is quite audible because it’s 10 dB higher than your threshold of hearing, your earplugs will be attenuating at least 25 dB (10 + 15) if they render sound 2 inaudible.

    I went ahead and tried your test and it made us realize that with our earmuffs that are the highest NRR we could find and with our earplugs also with the highest NRR that we would have to do a better job controlling the “source” of the sound. I can’t believe it took us this long to look for a better solution. Thanks-

    The National Hearing Conservation Association (NHCA) hosted a workshop specifically focused on hearing protector fit-testing during its meeting in February last year. The workshop will be featured again this year at the NHCA meeting in New Orleans (http://www.hearingconservation.org).

    There were seven vendors that participated, two of the solutions were from the NIOSH Pittsburgh Research Laboratories and the Division of Applied Research and Technology. Other vendors included 3M/EAR, Sperian Protection, WorkPlace Integra, Phonak and Michael and Associates. The fit-testing solutions range from psychophysical methods (such as the NIOSH QuickFit and QuickFitWeb) to the microphone in real ear measurements. The important point to note is that if you haven’t tested, then you do not know the attenuation of your protectors.

    QuickFitWeb is really a wonderful product. I enjoyed reading the information in the post. This type of Hearing Test online helps people to know about their hearing level and they can take steps to protect them.

    I did not get chance to try it but it really seems great. I will surely try this. Thanks for sharing.

    Pros:1. simple 2. fast 3. Easy pass/fail indicates if HPD attenuates > / 15) = good fit / good to go, when in fact even 15dB from a 33dB NRR product still shows that the product is not being worn correctly or doesn’t not fit.

    There is a huge difference between obtaining 15dB from and EAR classic and getting 28dB from an EAR classic. One suggests a poor seal/fit and one suggests a good seal/fit and 2. Like every other fit test product, it doesn’t verify that adequate protection is provided each and every day.

    I’d rather see an actual attenuation value than a pass/fail.

    2. Like every other fit test product, it would need to be repeated across multiple days in order to provide evidence of habitual use and consistent attenuation.

    3. Like every other fit test product, it doesn’t guarantee that the employee wears the HPD correctly each time and wears them every time it should be worn.

    Don’t get me wrong; I think there is value in HPD fit testing systems when used as a fit training tool, but I think that most consumers/employers see them as a panacea, that one measurement will provide sufficient documentation that you have a good hearing protection program. Fit testing does not replace the need for daily HPD monitoring on the part of the employer. It’s much like the value of an area sound survey compared to dosimetry results or the value of sinlge day/partial day dosimetry sample compared to multiple dosimetry samples.

    Consumers/employers should exercise common sense when considering any HPD fit test system:

    1. What is the motive?

    2. What are the expectations?

    3. Are the motives & expectations reasonable?

    Can this system be modified to measure the real-world attentuation first, followed by the non-attentuated threshold? By “real-world”, I mean pulling someone off the production floor without him/her having a opportunity to readjust their HPDs. Anytime you bring an employee into a test session and ask them to put insert their earplugs, they will more likely than not try to insert them the “correct” way for the test, regardless of how they use them on a day to day basis. The second sound would need to be 15 dB quieter than the first.

    Keep on fighting the good fight!

    This looks like a great product. I am a musician and I am looking for something to protect my ear. I am afraid that my hearing will be affected one day for taking damage from too much noise.

    I would like to know about NRR. When we see a label such as 27dB NRR, is it the same as saying that the hearing protector with attenuate 27dB SPL. Is it possible to say that 27dB NRR is the same as 27dB SPL? If not how much is 27dB NRR in SPL?

    Thank you.

    What a great initiative.

    I see people with improperly fitted hearing protection all the time and continually scratch my head about it. I mean, what’s the point.

    Here they go and spend good money on quality safety products and then fail to take advantage of the mountain of online information on how to use and fit it properly.

    It’s for that reason that something like Quickfitweb is sorely needed and I’ll definitely start spreading the word about it.

    Please share this post to raise awareness of this important issue.

    Tanya Green
    Please stay safe and use safety equipment properly.

    Can you recommend a good sound level meter for under $100? There are many different models and costs range from $29.00 to over $500.00. If there are good low cost models available, then the average person can purchase one to use to know when hearing protection is warranted.

    Good study, though obvious results. Hopefully NASCAR will help develop better hearing protection, like they have developed better safety equipment for other applications.

    Thank you for your interest in NIOSH’s research on work-related hearing loss. NIOSH has developed a free sound level meter application (app) for iOS devices. You can learn more about this tool and download the free app here: https://www.cdc.gov/niosh/topics/noise/app.html.

    As for sound level meters under $100, NIOSH does not endorse any particular products. However, you can find general recommendations for noise exposure instrumentation in the 1998 NIOSH Occupational Noise Exposure [https://www.cdc.gov/niosh/docs/98-126/] criteria document, which recommends a device that conforms to the “Type 2” American Standard Specification for Sound Level Meters (ANSI S1.4). Commercial sound level meters that comply with this standard will list it among their technical specifications.

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