Tag Archive: NIOSH

The unintended consequences of CDC’s guidelines for preventing hearing impairment

by John Drinkwater, Founding Member, The Quiet Coalition

If you follow the Centers for Disease Control and Prevention (CDC) recommendations to protect your hearing then be prepared for isolation and depression. The CDC’s February 2017 issue of Vital Signs states that continued exposure to unsafe sound levels can cause stress, anxiety, depression, isolation, and other health issues. So in order to protect your hearing, the CDC recommends everyone:

  1. Avoid noisy places.
  2. Use earplugs, earmuffs and noise canceling devices when in noisy places.

Amplified sound levels at restaurants, retail stores, movie theaters, health clubs, nightclubs, and other public places often are unsafe.

Following recommendation No. 1: You don’t go.

Following recommendation No. 2: Your ears can’t function properly.

Imagine if the “solution” to second hand smoke at a restaurant was to wear a protective mask over your nose and mouth. How could you possibly communicate and enjoy your meal? Hearing “protection” simulates the effects of hearing loss and inhibits your ability to communicate and enjoy the event. It also trains your ears to get used to the effects of hearing loss and may inhibit recognizing gradual hearing impairment.

The National Institute for Occupational Safety and Health (NIOSH), a part of the CDC charged with conducting research and making recommendations for the prevention of work-related injury and illness, is highly critical of earplugs and earmuffs and recommends they should only be used when engineering controls are not feasible to reduce noise levels. According to NIOSH, the noise reduction rating system (NRR) used for earmuffs and earplugs greatly overstates “protection” and therefore is not NIOSH approved. Workers often do not use hearing protectors properly, and they interfere with communication. If earplugs are removed for a short period in order to communicate, there can be immediate and irreparable injury. Even double protection (earplugs and earmuffs) is inadequate when exposure exceeds 105 dB.

Manufacturers mislead the public with overstated marketing claims. A Dow Industrial company markets their “Professional Earmuff” as “Our Highest-NRR Rated Earmuff (30 Decibels), Patented Twin Cup Design.” The really small print in the inside of the box states the Company:

[M]akes no warranty as to the suitability of NRR as a measure of actual protection from any noise level since such protection depends on the sound level (loudness), how long you listen to the loud sound, and how well you fit the earplugs (sic) in your ears…The NRR is based on the attenuation of continuous noise and may not be an accurate indicator of the protection attainable against impulsive noise such as gunfire…[Company] recommends reducing the NRR by 50% for estimating the average amount of noise reduction provided.

Furthermore, no type of hearing protection or noise canceling device protects against low frequency sounds, which travel through your body causing stress and may damage unborn children. Accordingly, NIOSH’s primary recommendation of the most effective way to prevent noise-induced hearing loss (NIHL) is to “remove hazardous noise from the workplace or remove the worker from hazardous noise.”

If you follow the primary CDC and NIOSH guideline, avoiding noisy places, it results in the same isolation, depression, and other issues associated with hearing impairment. The only healthy solution is requiring safe amplified sound levels so no hearing protection is necessary–it doesn’t cost anything to Turn Up the Quiet.™ There are many architecturally safe and pleasing ways to reduce sound levels in public places: breaking up an open floor plan, using materials that absorb or diffuse sound on wall and ceiling surfaces, installing carpeting, curtains, and tapestries, and using attractive acoustic panels, to name a few. It is also good for business.

After meeting with a local health club, they agreed to institute a new “quiet” class with no amplified music on a trial basis. Management was surprised to hear positive comments from members who had simply stopped coming to classes due to the unsafe volumes. They learned that some members with hearing aids took them out, put in earplugs, and still found the classes unbearable. In a few months they added two more quiet classes.

It’s OK to ask the grocery store, the clothing store, and other retailers to turn off the amplified music while you are shopping. Many will happily accommodate you, and it encourages others to do the same. Some businesses are establishing regular “quiet” hours of operation and finding more satisfied, and even new, customers who spend more time at the establishment.

In addition, “silent discos” are gaining popularity, where instead of amplifying music through speakers it is “silently” delivered via Wi-Fi to smartphones for patrons to listen without disturbing others. The local mayor wants to try it as part of the Summer Concerts in the Park series. It will allow those who may not want amplification to enjoy the Park, and won’t interfere with nearby businesses or residents. The same technology can be applied to other music events such as outdoor exercise, and speech events, such as public ceremonies, political speakers, and other large public gatherings.

These and other creative ways to avoid unsafe levels will allow all of us to fully participate and enjoy public gatherings without the risk of injury.

John Drinkwater is a composer, musician, and attorney with a background that includes science and architecture studies. He is the founder of secondhandsound.org, and he also owns the trademark Turn Up the Quiet™ All Rights Reserved.

Originally posted at The Quiet Coalition.

Text Copyright 2017 John Drinkwater
Photo Copyright 2014 secondhandsound.org
All rights reserved

Looking for a free professional grade sound level meter app?

Photo credit: NIOSH blog

Look no further: Introducing the new NIOSH Sound Level Meter App. Yes, the National Institute of Occupational Safety and Health (NIOSH) has just released a free sound level meter app for IOS (Apple) devices. Recognizing that “most of the apps on the market are oriented at the casual user and lack the accuracy and functionality necessary to conduct occupational noise measurements, NIOSH hearing loss researchers collaborated with an app developer, EA LAB, to create an iOS based sound level meter app that measures and characterizes occupational noise exposure similar to professional instruments.”

NIOSH has developed this app so that “workers around the world [can] collect and share workplace (or task-based) noise exposure data using their smartphones.” And once the data has been collected, “[s]cientists and occupational safety and health professionals could rely on such shared data to build job exposure databases and promote better hearing health and prevention efforts.”

NIOSH is making the app available to anyone who would like to download it. Click here to learn more about the app and for the link to download it at the App Store. NIOSH is looking for any and all feedback about the app and asks that you help them spread the word about this new tool for protecting workers’ hearing.

Thinking about downloading a sound measurement app?

Read this National Institute for Occupational Safety and Health (NIOSH) review first:  So How Accurate Are These Smartphone Sound Measurement Apps?

Scroll to the end of the blog post for a November 2016 update to NIOSH’s initial 2013 study.

Headphones marketed as safe for children aren’t!

kid-wearing-headphones

By Daniel Fink, M.D.

A new analysis on “the best kids’ headphones” by The Wirecutter, a product recommendations website owned by The New York Times, as reported in the New York Times science section, found that headphones marketed as “safe” for children’s hearing were louder than advertised. The Times’ article did not adequately reflect the extensive and thoughtful analysis by The Wirecutter’s reviewers, Lauren Dragan and Brent Butterworth. Their review deserves to be read (and reread) in its entirety, as it is without doubt the most complete and scientifically sound review about any noise topic that I have seen in the popular media.

The Wirecutter review mentions that two problems with headphones marketed as “safe for children”: (1) that the headphones are louder than they claim to be, and (2) that manufacturers are using an industrial-strength occupational noise exposure level as a safe noise level for children. The review doesn’t emphasize the latter point enough.

I discuss the origin of the 85 decibel noise exposure standard in detail in an editorial in the January 2017 issue of The American Journal of Public Health. The 85 decibel volume level at issue was developed by the National Institute for Occupational Safety and Health (NIOSH) to protect workers’ hearing. It comes with strict time limits–an 8-hour day, 240 days a year, for a 40-year work career–and even then does not protect all workers from hearing loss. NIOSH discussed the difference between an occupational noise standard and a safe noise level for the public earlier this year in a blog post titled, “Understanding Noise Exposure Limits: Occupational vs. General Environmental Noise.” The NIOSH post makes it very clear that 85 decibels is not a safe noise level for the public, and it certainly is not safe for toddlers or children who may be listening to music or watching videos for more than 7 hours a day, every day. In addition, children, and especially teens, are exposed to other loud noise sources–action movies, sports event, etc.–so their total noise dose likely approaches dangerous levels.

Children’s ears may be more sensitive to noise than adult ears. First, there is no doubt that an 85 decibel headphone speaker is closer to a child’s eardrum because the external auditory canal is shorter in children than adults. (Noise follows the inverse square law, so the closer a noise source is to the ear the louder it is.) Second, it’s unlikely that children will limit their listening to just 240 days a year, on average they will live for almost 80 years, and in the course of their lifetimes they will undoubtedly be exposed to more noise, in gyms, parties, rock concerts, sports events, and the like. A child’s delicate ears have to last her a whole lifetime.

Studies of auditory acuity in so-called primitive populations show that significant hearing loss in old age is not inevitable. These studies are not available online, so I can’t provide links, but the classic studies were done in the 1960’s by Rosen and colleagues in the Mabaan population in the Sudan, and by Dickson and colleagues in the Kalahari Bushmen. Rosen found that the Mabaan could carry on a conversation at normal speech volumes while facing away from each other at a distance of 100 yards. Dickson wrote that the Bushmen could hear an airplane 70 miles away. As noted in The Wirecutter review, acute hearing was a matter of life or death for our primitive ancestors, either to find food or to avoid being a predator’s meal. The Rosen and Dickson studies suggest that hearing loss so commonly seen in the U.S. is likely not part of normal part of normal physiological aging, but rather is noise-induced hearing loss–i.e., the result of a lifetime’s exposure to excessive noise. If one starts listening to 85 decibel sound at age 3, hearing loss and hearing aids may be inevitable–and at an earlier age than in the past.

What can be done to protect children’s hearing from dangerous consumer products marketed to them? The federal agencies charged with protecting the public should do their jobs. The Federal Trade Commission should take enforcement action on the grounds of false advertising against vendors claiming that headphones with the 85 decibel volume limit are safe for children. They may be safer than headphones without a volume limit, but they are by no means safe, especially without recommendations for time limits on use. The Consumer Product Safety Commission should require warning labels on headphones, earbuds, and personal music players, stating “LOUD MUSIC CAUSES DEAFNESS!” The pediatric community should do more to educate parents about the dangers of noise for children. And parents must step up and demand truly safe products for their children or deny their children access to products that will destroy their hearing.

Dr. Fink is a leading noise activist based in the Los Angeles area.  He serves on the board of the American Tinnitus Association, is the interim chair of Quiet Communities’s Health Advisory Council, and the founding chair of The Quiet Coalition, an organization of science, health, and legal professionals concerned about the impacts of noise on health, environment, learning, productivity, and quality of life in America.

CDC addresses noise exposure and health

Yesterday, the Centers for Disease Control and Prevention (CDC) posted content on its website addressing Environmental Noise Exposure and Health.  This content looks at a number of issues, including what is hearing loss, sources of environmental noise, and the public health burden from noise and hearing loss.

Under a section titled “Recommendations and Guidelines,” the CDC discusses noise exposure limits.  The CDC notes that the Environmental Protection Agency identified 70 dB as the average exposure limit to environmental noise for the general public, as did the World Health Organization (WHO), which “recommend[ed] that noise exposure levels should not exceed 70 dB over a 24-hour period, and 85 dB over 1 hour period to avoid hearing impairment.”  Occupational noise exposure limits established by the Occupational Safety and Health Administration and National Institute for Occupational Safety and Health for an 8-hour workday are also mentioned.

Kudos to the CDC for posting this material on their site and giving noise exposure the attention it deserves.  Noise-induced hearing loss and other injuries are mostly preventable, and the failure to educate the public on appropriate exposure limits is significant.  As the CDC states, the “National Health Interview Survey (NHIS) found that in 2014, an estimated 21.0% of adults aged ≥18 years had difficulty following a conversation amid background noise, 11.2% had ringing in the ears [ed. note: tinnitus], and 5.9% had sensitivity to everyday sounds [ed. note: hyperacusis].”   In short, noise-induced hearing loss, tinnitus, and hyperacusis affect more than a third of the population of the United States.  Given the CDC’s mission to control and prevent disease and injury, one hopes this is the first of many steps taken to educate the public, advise federal, state, and local governments,  and rein in a preventable health epidemic.

 

Want a side of peace and quiet with your meal?

You are not alone: Diners want noise off the menu.

NOTE: The statement in the article that “[t]he Centers for Disease Control and Prevention recommends less than eight hours of sustained exposure to noise louder than 85 decibels,” is wrong in its implied scope.  In February 2016, the National Institute for Occupational Safety and Health (NIOSH) posted an article on its Science Blog that stated that the 85 dBA noise exposure limit was intended only as a limit for occupational noise exposure and not as a safe noise exposure limit for the public at large.  See, NIOSH Science Blog clarifies difference between occupational and general noise exposure limits.  According to Daniel Fink, M.D., a leading noise activist, the only evidence-based safe noise exposure level for the public was calculated by the Environmental Protection Agency to be 70 dB (unweighted) average noise exposure for a 24 hour period.  See, Information on Levels of Environmental Noise Requisite to Protect Public Health and Welfare with an Adequate Margin of Safety.

Safe noise exposure for the general public

Daniel Fink, M.D., Interim Chair of the Quiet Communities Health Advisory Council, has written a post for the Quiet Communities’s blog that tackles a question which is rarely addressed: What noise level IS safe for preventing hearing loss?

In his post, Dr. Fink discusses the seeming contradiction between a 1974 Environmental Protection Agency (EPA) determination that “a 24-hour average noise exposure level of 70 decibels (dB) or less prevent[s] measurable hearing loss over a lifetime” with statements from various governmental and nonprofit organizations that suggested that “a much louder noise level − anything up to 85 dB − was safe for our ears.”  In the course of researching the issue, he received a communication from the National Institute of Occupational Safety and Health (NIOSH) that explained where the 85 dB figure came from; the information in that communication formed the basis of a post on NIOSH’s Science Blog in February 2016 (which is discussed here).

Long and short, the NIOSH communication explained that the 85 dB was an occupational noise exposure standard developed to protect workers over a lifetime of work, whereas the EPA determination of 70 dB averaged noise exposure over 24 hours was believed to protect the general public from hearing loss over a lifetime.  As Dr. Fink notes that the clarification of the difference in noise exposure limits is important in setting public policy and protecting public health, and he concludes that, based on his research, “[t]he much lower 70 dB average noise exposure level is the only published safe noise level to protect the public’s hearing.”

 

NIOSH Science Blog clarifies difference between occupational and general noise exposure limits

Many people are confused about what is a safe noise limit for the general public because the only noise limit the public may have heard about is the 85 decibel recommended exposure limit (REL) that National Institute for Occupational Safety and Health (NIOSH) established for occupational noise exposures.  Fortunately, the NIOSH Science Blog has just posted an informative piece* that discusses acceptable RELS for both, titled: Understanding Noise Exposure Limits: Occupational vs. General Environmental Noise.

The authors state that in 1998, NIOSH established the REL for occupational noise exposure to be 85 decibels based on an 8-hour shift for a 5-day work week, adding that the REL “assumes that the individual spends the other 16 hours in the day, as well as weekends, in quieter conditions,” and cautioning that “the NIOSH REL is not a recommendation for noise exposures outside of the workplace in the general environment.”  The difference between the occupational and general environmental noise exposures is that:

The NIOSH REL is not meant to be used to protect against general environmental or recreational noise; it does not account for noisy activities or hobbies outside the workplace (such as hunting, power tool use, listening to music with ear buds, playing music, or attending sporting events, movies and concerts) which may increase the overall risk for hearing loss.

The authors point out that a 1974 Environmental Protection Agency (EPA) report recommended 70 decibels over a 24-hour average exposure limit for general environmental noise (while noting the EPA’s caution that its recommendation was not a standard, specification, or regulation).  This recommendation was determined in a similar manner as the NIOSH REL, but it’s focus was on general environmental noise and not the workplace.  As the EPA report states, their recommendation “was chosen to protect 96% of the general population from developing hearing loss as well as to protect ‘public health and welfare.’”

The authors note that both limits “are based on the same scientific evidence and the equal-energy rule,” but “are designed to protect against different problems.”  As a result, the limit values differ because “the EPA limit was averaged over 24 hours with no rest period while the NIOSH limit is averaged for just 8 hours and includes a rest period between exposures,” and the EPA limit includes an allowance “to protect against exposures for 365 days a year versus the NIOSH REL’s calculation that aims to protect against work place exposures for 250 working days a year.”   The authors add that “the EPA limit did not consider cost or feasibility of implementation as the Occupational Safety and Health Administration (OSHA), in accepting a NIOSH REL as the basis for a mandatory standard, [was] required to do under the Occupational Safety and Health Act of 1970.”

Long and short, the authors conclude that the 85 decibel REL is a work standard that neither mandates nor recommends decibel limits for the general public.  Rather, it is the EPA’s recommendation of 70 decibels that provides the appropriate exposure limits for the public with regard to general environmental noise.

*The post was prepared by NIOSH engineer, Chuck Kardous, MS, PE; NIOSH audiologist, Christa L. Themann, MA; NIOSH research audiologist Thais C. Morata, Ph.D., who is also the Coordinator of the NORA Manufacturing Sector Council; and W. Gregory Lotz, Ph.D, Captain, US Public Health Service, Division Director of the Division of Applied Research and Technology (DART), and the manager of the NORA Manufacturing Sector Council.