BAP Acoustics

Sound, Noise and Vibration Consulting Engineers

Rock on! Quietly.

If you’re familiar with our work and philosophy, you’ll know that we’re all about planning-stage noise mitigation measures vs/ so-called soundproofing… the latter almost worthy of MythBusters*. You’ll know BAP Acoustics gives no bandwidth to purveyors of noise-cancelling miracle materials and quick-fix solutions with no scientific basis. That said, there are ways—even in older homes—to enjoy noisy hobbies without inciting the wrath of your entire neighbourhood.

*In their 18-season run, the lads did not tackle the veracity of soundproofing, but in a 2013 episode titled Fright Night, they did answer the question "Can certain sound frequencies persuade people that an area is haunted?"

Whether you’re an architect or a budding musician anxiously wondering where to play that drum kit you couldn’t afford not to buy on eBay (ideally a neighbour-friendly electronic one), it’s worth noting that noise exposure—surely not the best way to broaden your neighbours’ horizons—can be reduced by eliminating the source of noise, substituting the source with a quieter one, applying engineering modifications, and using protective equipment.The best way to reduce exposure to noise is to engineer it out at the design stage. (Source: ccohs.ca)

Rock tumbling to tame stay-home tedium? Huh.

This blogger’s post ideas alight from all over the place, including nature and the (varying degrees of) great outdoors. Last summer, music and arts festivals inspired a piece on natural amphitheatres, while summer 2020—with its pandemic-driven dearth of anything resembling an event—brought quieter, simpler pleasures to the fore.

How can I get them to stay this colourful and shiny?

While visiting family in British Columbia’s Okanagan Valley (known for its bountiful orchards, world-class vineyards, and spectacular lakes), I rediscovered my lifelong delight in collecting pretty rocks. And, not for the first time, I experienced a tiny bit of that sad trombone (wuh wuh wuhhh) disappointment at the lacklustre effect of hot, dry air on previously wet rocks. Of course, I brought a few home anyway… and got to thinking about rock tumblers. How much do they cost? Where could I buy one? The one thing I recalled hearing about them is that they’re very noisy. I began to wonder, “How noisy, exactly?” What if I could find a relatively quiet one? Where to go from here?

OK, you’re cute, but even sad trombones make noise. Wuh-wuhh.

My first inclination? To do what I usually do before buying any new item worth more than a few bucks:

Homework.

If there’s anything working with BAP Acoustics has taught me, it’s the value of mitigating anticipated noise issues in the planning stages a project. So, I conducted a Google search for the seemingly oxymoronic term “quiet rock tumbler”.

Who’d have thought that this is actually—in the minimalist vernacular of today—”a thing”?

I don’t own a rock tumbler, so if I wanted to tumble my little treasures to their potentially lustrous glory, I’d consider buying one. A rock-collecting friend received one for Christmas some years ago and uses it all the time; it lives in his garage. However, when he’s in the garage with rocks a’tumble he wears industrial grade hearing protection.

This thing is loud. And I assumed all of them were, until my Google search yielded hits that gave me pause. Renowned geologist Hobart King loves rocks so much he launched an impressively comprehensive website dedicated to tumbling ’em. Having spent over 40 years studying the physical properties of rocks and minerals, King strikes me as a trustworthy source of expertise. Over 50 years ago, King’s father noticed his son’s fascination with rocks and gifted the boy his first tumbler one Christmas. King still owns it, and it’s in working condition.

Although RockTumbler.com is an e-commerce site, it does offer enthusiasts a wealth of articles and resources. King’s article How Much Noise Does a Tumbler Make? answers that question in detail. Using a digital sound level meter, King’s team tested several tumblers to measure and compare their noise levels. Their charts below illustrate results:

Key takeaway? Soft rubber barrel tumblers with quality motors are quiet; their inexpensive plastic counterparts tend to be very noisy. (A colleague of King’s tested one in his basement and could hear the noise in his second-floor bedroom.) Although RockTumbler only delivers the products it sells within the US, a decent selection can be found on Amazon.ca.

Although some tumblers do make “enough of a racket to rouse a small animal from the dead” according to one of the resident experts at hobbyhelp.com, “these are certainly the minority, and there are various precautions you can take to ensure your rock tumbling doesn’t anger your nearest and dearest.”

But I just picked one up at a yard sale!

Or maybe you’ve just remembered that childhood rock tumbler, still tucked away somewhere in your parents’ garage. In any case, what—if anything—can be done to shush an unacceptably noisy bucket of rocks?

I spent some time browsing through member posts on rock hobbyist forums and discovered that the question of how to silence a noisy rock tumbler arises often. Some of the advice offered seems worth exploring; people often suggest some variation on building a box or other enclosed structure and lining it with an insulative material. It quickly became apparent how complex an engineering task this could be, given that rock tumblers are motor-run, and motors tend to get hot… No need to add that kind of spark to an otherwise relaxing hobby.

A few people shared their own DIY stories of success in building tumbler homes allowing for both sound attenuation and heat ventilation. Whether or not any of these should come with the warning “Don’t try this at home” is the question I respectfully leave entirely to you, gentle reader. To paraphrase a retro sci-fi spaceship doctor, “Dammit, folks! I’m a blogger, not an HVAC engineer.”

In this members forum thread on rocktumblinghobby.com, the original poster comments “I have just sold my home and will soon be moving to an apartment (haven’t chosen it yet, but am leaning towards a particular one). Any advice on the ins and outs of tumbling in an apartment?” Four years later, the same poster—having presumably settled into his flat—appears ready to house a potentially noisy unit of fun. We hope one (or a hybrid) of your fellow enthusiasts’ suggestions in the thread worked out for you, dscratch!

How noisy are your hobbies? We’d love to hear (about) them on Facebook, Twitter, or LinkedIn!

If you’re dealing with a noisy neighbour—or worried that you might be a noisy neighbour—please contact us directly to discuss your situation; we’d be happy to help.

Let’s hear it for her too!

Women’s innovative contributions to acoustics (Part II)

In Have you heard about her? Women’s innovative contributions to acoustics (Part I), we started off with a historical perspective, acknowledging Hedy Lamarr’s ground-breaking work in developing the frequency hopping spread spectrum, a technology still used in underwater acoustic communication and recognized as the foundation of WiFi, GPS and Bluetooth.

We also introduced distinguished acoustics researcher Bridget Shield, best known for her studies on the effects of noise on children, and Dame Ann Dowling, a British mechanical engineer lauded for her research in combustion, acoustics and vibration. While Shield retired in 2014 and Dowling last year, the women no doubt served as inspiring role models for younger generations. Here then, are six women currently at the peak of their careers.

Lily Wang

Professor & Associate Dean at the University of Nebraska College of Engineering, Lily Wang also served as president of the Acoustical Society of America (ASA). She specializes in room acoustics and noise control and loves encouraging young people to explore acoustics as a career.

Her substantial body of research includes a number of articles on variations in restaurant soundscapes. Chris Berdik’s January 2020 Popular Science article It’s not just you: Restaurants have gotten too loud. But there are some fixes addresses, among other issues, the problems inherent in restaurants that merge dining rooms with open kitchens and bar areas. “Architects aren’t trained to think about sound; they’re trained to think visually and spatially,” Wang states in the article. She is currently working with the ASA to establish guidelines for restaurants.

Mariana Lopez

Lopez is a Senior Lecturer in Sound Production and Post Production at University of York. A former Vice-chair of the Audio Engineering Society (UK Section), she passionately advocates for accessibility and gender equality within the acoustic industries.

An important link exists between accessibility and design practice, Lopez explains in her recent article Fostering inclusivity: The power of assistive music technology. “The concept of Universal Design stems from a desire to create products and environments free of usability barriers—treating accessibility as integral to their proper functioning.” she writes. “Universal Design champions the idea that products and environments designed to be accessible for people with disabilities will end up benefiting everyone. For example, a ramp might be initially designed to provide access to people using wheelchairs, but they can also benefit those carrying suitcases.”

Susan Witterick

In addition to her role as Director of dBx Acoustics, Witterick serves as an Ambassador with STEM (Science, Technology, Engineering, and Mathematics). both an acronym and a UK-based organization in which volunteers encourage and inspire students interested in STEM career paths. These students are still predominantly male.

Witterick graduated in 1998 with a BSc (Hons) in Audio Technology, one of only three women in her year. She explores at length in a thought-provoking Medium article possible explanations for “why women still aren’t routinely considering STEM as a career path, and what can do —all of us—to change this.”

Poppy Szkiler

Szkiler’s grandfather, John Connell, founded the non-profit Noise Abatement Society in the UK, so it’s fair to say she came naturally by her interest In the Pursuit of Silence, also the title of an award-winning documentary film she co-produced.

Szkiler also runs Quiet Mark™, which awards “the International mark of approval for low-noise technology, services and solutions launched by the Noise Abatement Society in 2012 to create a stress-free aural environment in the home, at work and in public spaces.”

Quiet Mark™ achieves this through the following objectives:

  • Encourage manufacturers to factor in low-noise at design stage and provide them with a unique selling platform
  • Give consumers more informed purchasing choices
  • Raise awareness about the positive health and well-being implications of a low-noise, stress-free living and working environment

Johanna Bengtsson Ryberg

Relied-upon noise expert for Swedish media and at Arbetsmiljöverket (the Swedish Work Environment Authority), Bengtsson Ryberg holds a doctorate in Environmental Medicine and specializes in traffic noise. She writes about environmental noise in both English and Swedish.

“Community noise is a widespread environmental problem in Sweden, affecting children as well as adults.” she writes in her article A national project to evaluate and reduce high sound pressure levels from music. “Based on the findings of a national environmental health questionnaire, the noise sources that produced most annoyance in children were noise from other children and loud music.”

Have you heard about her?

Women’s innovative contributions to acoustics

Q:  What do Turner’s Classics and the world of acoustic inventions have in common?

A:  They both owe a debt of gratitude to this heroine, right here.

Hedy Lamarr juxtaposed with her influential work.

Although Hedy Lamarr wasn’t an acoustician per sé, the frequency hopping spread spectrum technique she developed with avant-garde composer George Antheil was a milestone invention in the field of information technology, one still used in underwater acoustic communication owing to its anti-interference and anti-fading properties. These same properties explain why the two friends are widely credited with paving the way for later, more complex inventions including WiFi, GPS and Bluetooth.

Best known as a shining star of golden era Hollywood, Austrian-born Lamarr personified the beauty and brains combo.

Picture it: 1941.

Lamarr’s fame soars as Hitler’s forces ravage. Not content to sit by photogenically as wanton destruction prevails, Lamarr draws on military engineering knowledge quietly gleaned during her brief marriage to a Viennese arms tycoon closely associated with both Mussolini and Hitler. Having fled from her domineering first husband a few years earlier, she enlists Antheil’s help to devise a means by which radio signals can guide torpedoes without detection or interception by “hopping” among numerous frequencies.

Sadly, military elite dismissed the technology, and it wasn’t employed during WWII. More sadly still, Lamarr and Antheil’s patent had long expired by the time frequency hopping was used during the Cuban missile crisis. Lamarr received no monetary compensation and lived to become an old and reclusive woman before due recognition came her way.

It seems probable, however, that Lamarr inspired and served as a role model for generations of women that followed… women like Bridget Shield and Dame Ann Dowling.

“Every engineering project is about making something that someone wants. It is very creative.”
— Dame Ann Dowling

Bridget Shield

A preeminent acoustics researcher nominated first female president of the Institute of Acoustics in 2012, Bridget Shield earned her academic credentials at Birmingham University in the UK, going on to serve as Professor of Acoustics at London South Bank University from 1986 until her 2014 retirement. Perhaps best known for her findings regarding the effects of noise on children and their learning abilities, the award-winning engineer expressed concerns that British architects were excessively focused on aesthetics—while overlooking factors necessary for healthy learning environments—in their designs of much-needed new schools.

“The spacious, light-filled palaces going up under the government’s multi-billion pound school building bonanza […] look wonderful,” Shield writes, “and, with their lack of dark corners, make pupils feel safe. But how well can pupils hear inside these educational glasshouses?”

New as well as older schools often feature overly reverberant and/or noisy classrooms in which children struggle to hear while teachers struggle to be heard. Current architectural trends (if you’ll pardon the word choice) amplify the problem, incorporating as they do large, open spaces as well as hard reflective surfaces like glass and steel. “These are precisely the types of material that make for echoing, noisy spaces,” Shield explains, noting detrimental effects including compromised working memory (and consequently, scholastic performance) in children, as well as voice and throat problems among teachers.

The techniques for reducing reverberation and noise in schools are well known, Shield states in a 2008 article. They include:

  • Careful choice of the site, layout and design of school buildings to ensure noise sensitive rooms such as classrooms are not adjacent to busy roads or railways.
  • Adequate sound insulation to reduce the transmission of noise from outside to inside, and between classrooms.
  • Adequate amount of acoustic absorption on ceilings and corridors, and carpets or other resilient floor coverings to reduce reverberation.
  • Use of quiet building services such as ventilation, heating and lighting.

Dame Ann Dowling

A prominent British mechanical engineer, Dame Ann Patricia Dowling OM DBE FRS FREng is renowned for her research in combustion, acoustics and vibration, particularly with regard to her focus on efficient, low-emission combustion and reduced road vehicle and aircraft noise.

Dowling chaired the 2013 Global Grand Challenges Summit, and in an Engineering and Technology Magazine interview around that time expressed her concerns about the critical shortage of British engineers in general and female engineers in particular:

Despite the enormity and importance of these [energy efficiency and noise mitigation] projects, the shortfall in British engineers is huge. Dowling often gives talks in schools, but the message is still not getting across. In particular, it’s not getting across to her own sex.

The feedstock of girls reading engineering at university is around 17 per cent, Dowling thinks. Why? The perceived lack of social relevance and flexible working hours perhaps? “Nothing could be further from the truth,” protests Dowling. “Every engineering project is about making something that someone wants. It is very creative.”

However, Dowling says her department has a higher percentage of female engineers than elsewhere. Could this have something to do with herself as figurehead? “I don’t think I can claim that.” Instead, she puts it down to offering a broad strand of engineering. However, later on she concedes that it’s always useful to see someone active in your field and doing well. 

We encourage you to read Part II of our tribute to women in acoustics.

Best of 2019: 9 acoustic services questions answered

Ever wondered what acoustic engineering consultants are typically asked to do when they’re… consulted? Maybe you have an acoustics-related problem of your own but aren’t sure what questions to ask? First of all, please don’t hesitate to contact us and express your concerns, because at BAP Acoustics, we believe there are no wrong questions, especially not when they elicit sound advice. Secondly, we hear certain types of questions so frequently we feel they warrant their own blog post, so please read on. You may see your own question—or one relevant to it—addressed below.

In compiling and reviewing these questions, we realized that much—although not all—of our work entails solving problems as opposed to preventing them. Budgetary constraints, environmental consciousness, and heritage building preservation arise among the reasons people often choose to retrofit rather than build new structures. While we always present the most practical and cost-efficient remedial options available, these solutions can be far more expensive than a strata council, building manager, or homeowner might anticipate. Whether you’re designing, planning, building, or striving to make do with a less than ideal acoustic space, we hope you find useful information in the questions and answers that follow.

1) My company’s new office space has turned out to be disruptively noisy in the open-plan areas where most people work. And even between enclosed offices, there’s a lack of speech privacy. Can you help?

Yes, we can. In past cases similar to yours, we’ve come in after staff has left for the day. Simulating office noise in problematic areas allows us to assess and/or measure:

  • current sound insulation levels between offices or other cellular spaces
  • speech privacy between adjacent offices and circulation space
  • reverberation in open-plan areas.

We also inspect construction assemblies (a combination of materials or other items that serve a specific function when assembled) and identify acoustical issues that may be evident within space above a T-bar ceiling, as well as at the junctions of office separating walls with exterior walls.

Our measurements generate data, and our inspections inform us, enabling us to determine the remedial steps necessary to mitigate troublesome noise in your workspace.

While our services don’t include assaulting noisy office equipment, we do understand the therapeutic potential inherent in a DIY project of this nature.

2) The City has asked us to submit an acoustic report as part of the Development Permit application for our new residential project. Is this something you do?

Indeed it is. We’ve helped numerous developers submit acoustically compliant permit applications. Our process includes:

  • assessing (measuring) the road traffic noise at your proposed development site
  • predicting noise level impacts on building facades
  • calculating levels of noise transmitted into residential units
  • suggesting glazing and exterior wall upgrades to meet CMHC interior noise environment recommendations
  • issuing a report for submission to the City.

3) My client recently moved into an apartment unit, unaware that her upstairs neighbour had just installed new flooring. The resulting noise constantly disrupts sleep and compromises her wellbeing to the extent that she needs legal advice. Can you conduct testing and write an expert report for us in the event of litigation or a Civil Resolution Tribunal dispute?

Absolutely. In a case such as your client’s, we can:

  • measure the airborne and/or impact sound insulation of the separating floor-ceiling assembly by following the relevant ASTM standard(s)
  • document detailed test results
  • compare our measured Impact Insulation Class (IIC) and/or Sound Transmission Class (STC) ratings with Building Code recommendations/requirements, as well as compare results with the sound insulation performance that would have existed prior to the neighbour’s flooring change
  • issue a report suitable for use in litigation or application to the Civil Resolution Tribunal (CRT)
  • provide evidence in court if required.

4) We’ve recently completed a new building for a client who now claims noise levels exceed those specified in contract documentation. Would you be able to measure the levels and advise us how to reduce them to a contractually compliant state?

Yes, we provide both those services. We can measure:

  • levels of background noise from HVAC and/or other building systems
  • reverberation times in selected spaces
  • the sound insulation of partitions separating spaces of concern.

These tests allow us to compare measured performance with contractual requirements, as well as offer informed mitigation advice to bring acoustic performance in line with client expectations.

5) Our team is developing a luxury residential building, and we want to ensure that noise transmission between units is kept to a minimum. Can you help us design suitable separating partition assemblies?

Certainly. We’ve worked with design teams on numerous luxury residential buildings. In addition, we’ve acted, on behalf of condo owners and strata councils, as expert witnesses in warranty claims against developers. We’re aware that Building Code minimum performance requirements seldom meet owners’ expectations, particularly when those owners bought into high-end developments. We’re also cognizant of the need to increase performance when (as is frequently the case) a noise-sensitive room in one unit shares a separating partition with a noise-producing room in an adjacent one. We can recommend partition assemblies built to meet these higher standards.

6) Our apartment building has a fitness studio on the ground floor, and we often hear noise from dropped weights, workout music, and even amplified class instructors. We’re really hoping you can measure such noise and write a report to help us convince the studio to reduce sound levels.

We can help you. We’ve worked with both fitness studios and homeowners to reduce noise transmission from free-weight areas as well as from sound systems. We’ve also acted as expert witnesses in cases where noise from commercial activity adversely impacts homeowners. We’d be happy to come in and:

  • measure the noise in your apartment
  • document these measurements
  • compare our measured levels with published guidance
  • issue a report suitable for use in litigation or application to the Civil Resolution Tribunal (CRT).

7) A new road has been built close to our house. The resulting increase in traffic noise in our living room and bedrooms is truly annoying, so we’re looking for someone to measure the noise. Is it possible to compare the new noise level with what used to be the case before the road was opened? And if so, can you write a report we might use in litigation?

Yes, and yes. We have considerable experience in measuring transportation noise from road, rail and aircraft. Once we’ve obtained measurements, we can use them together with existing, future, or past road alignments to simulate outdoor noise propagation and determine impact on existing or future property. In this way, we’ll be able to compare your current noise exposure with pre-road construction levels. We’ve written many expert reports for use in litigation, and we can work with your lawyer to provide the service required.

8) I own a condo suite in downtown Vancouver. There’s an unidentifiable noise in my apartment almost 24/7, very loud. I’ve made complaints and reported to strata, but with no proof, I doubt anything will be done. So, I’d like to approach strata again with a report based on professional testing that determines the source of the noise. I’ll potentially go to court with this issue. Is this something you can help me with?

Yes. We can arrange for a suitable time to:

  • measure noise in your apartment
  • compare our measured noise levels with criteria recommended in published guidance
  • document our measurements
  • assess noise levels in a report suitable for use in litigation.

If your building manager can provide access to the rooftop, as well as mechanical and electrical rooms, we’d be able to locate the noise source, and subsequently offer design advice to mitigate troublesome levels.

9) I’m a lifelong hilltop dweller just above the town of Whoville, Suesslandia. I keep to myself and bother no one, yet every December the NOISE gets worse and worse. The insufferable Whos, if you can believe it—the tall and the small—gather in their silly town square and make the most obnoxious ruckus. (They call it “singing”.) My dog Max must be losing his hearing, because he doesn’t seem to mind it. If you can’t help me make these people listen to reason, I fear drastic measures may have to be taken. Sincerely, Mr. I.R. Grynch

Dear Mr. Grynch,
While we’re sorry to hear about your predicament, the Whoville Town Council assures us that residents are compliant with all bylaws and regulations. They suggest that you’re likely conflating “obnoxious ruckus” with “joyful sounds”, and we don’t, generally speaking, mitigate the latter. Quite frankly, we’re also rather concerned about your heart and feel it may benefit from skillful resizing, a procedure offered at Whoville General, we understand. We hope you can reach a mutually satisfying resolution with the townspeople, whom we found very hospitable… They invited us to a roast beast feast! Perhaps we’ll see you there?

Whoville’s tall & small, breaking out the joyful sounds.

From all of us at BAP Acoustics,
a joyous holiday season
and all the best in 2020!

Listen to your body

When noise becomes a health hazard

Sure, noise can irritate even the most serene among us. But to label it an actual health hazard, like air pollution? That’s pretty hyperbolic, isn’t it? It’s only noise, after all; it’s not like it’ll kill us or something. Is it? Well, yes and no…

Oh wait, when someone deems noise to be a health hazard, they must be referring to the kind of high-decibel din found in some industrial workplaces, right? Jack hammers, chainsaws, welders… industrial machinery makes industrial noise; that’s why workers wear protective gear. Doesn’t adherence to OHS regulations ensure safety? Again, yes and no.

Growing evidence, such as that gathered in the pivotal 2011 World Health Organization (WHO) study Burden of disease from environmental noise, suggests that surprisingly low noise levels can wreak all kinds of havoc with both our physical and mental wellbeing, especially when we’re exposed to them for extended periods of time. Excessive and/or prolonged noise exposure can disturb sleep, raise blood pressure, impair cognitive function, and increase risk of psychiatric disorders.

Excessive and/or prolonged noise exposure can disturb sleep, raise blood pressure, impair cognitive function, and increase risk of psychiatric disorders.

Since deleterious consequences of noise exposure happen at lower (seemingly innocuous) levels than those causing hearing damage, people may not even realize they’re at risk. Moreover, hearing loss itself can result from less extreme conditions than one might imagine. A 2013 study titled Environmental noise pollution in the United States: developing an effective public health response provides detailed findings and analyses.

The insidious, little-known effects of noise on sleep

Obvious sources of nighttime noise wake up and bring out the inner Grandpa Simpson in most of us. Who doesn’t want to shake a metaphoric cane at those drunk people arguing loudly mere feet from their bedroom window, punctuating extra-important points with thrown bottles? Or let’s talk about sanitation trucks that rumble on up curbside at hours this blogger defines as still, unequivocally, nighttime. On second thought, let’s not.

Sleep deprivation:
We don’t like it. Our hearts don’t like it.

Possibly the most surprising and frequently corroborated information my research for this post has yielded is that inaudible sounds can damage our hearing, and we’re especially vulnerable to a variety of noises at night, even if they don’t wake us up. Industrial hygienist Richard L. Neitzel, PhD defines microarousals as periods during which noise arouses the nervous system, but not quite enough to cause a person to wake up or remember the event and highlights their link to heart disease. “The normal restorative drop in blood pressure at night fails to occur when sleep is fragmented,” Neitzel explains.

Suppose you’re attempting to nod off. Even if you think you’ve blocked out the rumbles of downshifting trucks outside, your body hasn’t. Those adrenal glands are spewing pressure hormones. Your heart rate and blood pressure are increasing while your digestion is calling it a night. Your perpetually busy brain keeps on processing sounds while you slumber. As if sleep deprivation weren’t bad enough… Turns out we need to evaluate sleep both in terms of quantity and quality.

The effects of noise on cognitive function

Mounting evidence suggests that multitasking and interruptions (such as noise) compromise academic and work performance. Excessive noise has been shown to detrimentally affect cognitive function and communication, and thereby generate errors. This phenomenon is especially prevalent in urban environments, including schools and hospitals. The Center for Cognitive Studies in Medicine and Public Health, in collaboration with Columbia University, is collecting preliminary data to assess noise levels in the patient care environment during care team transitions, using sound measurement and simulation technology.

Children are at particular risk not only for noise-impaired cognitive development—but a host of other serious health issues—even before they’re born. In the 2016 study Noise as a health hazard for children: Time to make a noise about it, researchers from the University of New Delhi and the Hind Institute of Medical Sciences concluded:

Noise, a modern day curse of advancing infrastructure and technology, has emerged as an important public health problem. Exposure to noise during pregnancy may result in high-frequency hearing loss in newborns, growth retardation, cochlear damage, prematurity and birth defects. Newborns exposed to sound above 45 decibels may experience increase in blood pressure, heart rate, respiratory rate; decreased oxygen saturation; and increased caloric consumption. Noise exposure in older children may result in learning disabilities, attention difficulties, insulin resistance, hypertension, stress ulcers and cardiovascular diseases. Sudden exposure to loud noise can lead to rupture of eardrum. The damaging effects of noise pollution are more noticeable in large metropolitan cities, the hubs of urban settlements and industrial growth. Another concern is noise pollution inside the hospitals (particularly intensive care areas) that can lead to serious health consequences both for caregivers and for children. The issue needs to be addressed by both researchers and policy makers on an urgent basis. (Emphasis mine.)

Noise Annoyance and mental health

Also known as sound annoyance, noise annoyance can indeed be annoying enough to drive you mad, and it can certainly play a role in depression and anxiety. Wikipedia defines sound annoyance as “a feeling of displeasure associated with any agent or condition […] that is believed to affect adversely an individual or a group.”

While little research on how noise affects mental health have been conducted, a rigorous 2016 study based on 15,000 German residents concluded that noise annoyance is directly correlated with depression and anxiety in the general population. Though the residents lived under a flight path and aircraft noise emerged as the biggest culprit, road traffic, aircraft, railways, industrial, and neighborhood noise were also contributors.

A few studies have also addressed the effects of noise in hospitals and other healthcare environments, bringing to light, among other findings, the disturbing occurrence of ICU psychosis, a disorder in which intensive care patients experience a cluster of serious psychiatric symptoms. While medication (or lack thereof) can also play a role, the frequent distressing sounds that occur in such environments factor significantly.

Closing thoughts

Prior to the WHO’s ground-breaking 2011 study, very little was known about the multi-faceted extent to which excessive and/or prolonged noise can affect human health, and that of other species. The volume (no pun intended) of scientific evidence now available to us makes clear the importance of continued awareness raising and public education. Most urgently, the message that we need to mitigate harmful noise should reach the ears of policy makers everywhere.