What Do You Hear? – Are Hearing Aid Wireless Radiation Transmissions And Disease Rates Related?

In this guest post, Diane Craig explores how the newer digital wireless hearing aids may provide a stressor that could contribute to brain disorders such as Alzheimer’s and Parkinson’s, and she shares 6 ways you can be proactive and protect yourself:

As my husband and I age, we’ve started noticing how more and more of our contemporaries are being diagnosed with Alzheimer’s or Parkinson’s and that more and more of them are wearing hearing aids. From personal experience, we also know how much hearing aid technology has changed in recent years.

Hearing loss, Parkinson’s disease and Alzheimer’s dementia all are more commonly experienced by older people, of course. They also differ.

When surveyed in 2019, one thousand adults in the United States responded that they considered the top two most unpleasant ways to die to be cancer (number one at 49%), and “[a] neurological disorder such as dementia or Parkinson's disease” (number two at 30%). [ 1]

According to an American Parkinson Disease Association un-dated post, “Most patients die with Parkinson’s Disease and not from it. The illnesses that kill most people are the same as those that kill people with PD. These are heart conditions, stroke and cancer.” [2] (see this article on Cancer)

Nevertheless, the National Parkinson Foundation in 2004 and again in 2014 had listed Parkinson’s disease as “the 14th leading cause of death in the U.S.” [3 ]

Due to poor balance and coordination issues, Parkinson’s patients are among those at risk for death from unintentional injuries. And by 2020, a new category, Unintentional Injuries, had surpassed Stroke to become a 4th leading U S cause of death [4].

Deaths in another new 2020 category, Covid-19, were 3rd. [4]

These changes pushed Alzheimer’s disease from 6th to 7th place as a cause of death. [4]

Here’s my question: Could the newer digital wireless hearing aids improve hearing but also provide a stressor that could contribute to brain disorders such as Alzheimer’s and Parkinson’s? I decided to find out what the research says.

Hub’s Saga Part One

Hub [5] has had hearing loss probably since early childhood, though this wasn’t recognized until his draft board’s hearing test. Afterwards, instead of joining a tour to Vietnam, Hub caught the next bus home. He’s worn hearing aids for many years now.

Recently, Hub’s hearing aids had fallen apart. His old model couldn’t be replaced.

The newer models were somewhat less expensive than his old model had been. Still, they were costly. The hearing aid specialist showed Hub two options, both digital models that included wireless. One advantage of built-in wireless, the specialist explained, was that the hearing aids, by communicating with each other, could help Hub more easily determine a sound’s direction.

The bigger sales pitch was that Hub could connect his new hearing aids with other wireless devices such as cell phones.

Hub and I looked at each other. We didn’t own a smart phone. We didn’t want one. The hearing aids, like computers, would come with their wireless features already turned on. We wanted all wireless off. After being assured that this would be possible, Hub took his hearing test, chose the hearing-aid color that would appear behind his ear, and made an appointment for a fitting.

Wireless Radiation Possible Stressor: Frequency

Why did we want the wireless turned off? We knew that the cumulative impact from wireless radiation is a combination of three factors: the frequencies that are transmitted, the power densities of those pulsed transmissions when they reach one’s location, and the duration of exposures to them.

The frequencies used in wireless-enabled hearing aids are in the range of 2.4 GHz to 2.48 GHz. Bluetooth devices operate in this 2.4 GHz range. So do cordless phones, baby monitors, smart meters and microwave ovens.

Why do hearing aid manufacturers and others use frequencies so close to the one used for microwave ovens? [6]

Microwave ovens arrived first, shortly after World War II. The 2.45 GHz frequency they used worked great for heating water and fat, and most of the wireless transmissions could be confined inside the ovens. (Read more about Microwave Oven Radiation.)

Later, as wireless communication uses proliferated, the Federal Communications Commission created a wireless category called the Industrial, Scientific and Medical (ISM) frequency bands. These 2.4 GHz to 2.4835 GHz ISM bands don’t require any special licensing, and they are free for manufacturers of microwave ovens and other devices to use.

But are such devices safe for human use? Parts of me consist of water and fat, and my radio frequency radiation meter has, on more than one occasion, recognized microwave oven transmissions well into adjoining rooms.

Hub’s Saga Part Two

The fitting appointment lasted a long time. The model he had ordered didn’t come with any turning-off-the-wireless instructions, so the specialist called a tech support representative.

After a lengthy conversation, the specialist made the tech support representative’s indicated adjustments. Hub tried on the new hearing aids and seemed happy with their comfort and the sounds he could hear. I took out my meter, one that measured the radio frequency radiation that’s transmitted by all wireless devices. I turned the meter on and held it up to Hub’s head. Nothing changed. Whew! Click here to discover how to measure Radio Frequency Radiation in your home.

Sometime later, we visited a friend who wanted to show us a space she’d turned into a faraday cage, because faraday cages block wireless radiation. The moment Hub entered, her meter started beeping. Matter-of-factly, she said, “It’s probably because of your hearing aids.” As Hub left the area, her meter went silent.

That day, I had a different radio frequency radiation meter with me, so I tested with it just as she had. Like my previous meter, but unlike hers, this meter didn’t beep when the hearing aids were still attached to Hub’s ears. It did beep, however, once he’d removed the hearing aids. It stopped beeping when he opened the backs and inactivated the batteries.

Knowing that whatever had been done during Hub’s initial appointment to turn wireless off was not working now, we went back to the hearing aid specialist….

Wireless Radiation Possible Stressors: Power Density and Duration of Exposure

By this time, I’d read about a 2019 research study that exposed mice to 2.4GHz wireless radiation for two and four hours. It had concluded, “Our results provide evidence that Wi-Fi signals increase lipid peroxidation, SOD activity (oxidative stress), apoptosis and CDKN1A and GADD45a overexpression in mice placenta tissue.” [7] See this article on “Is WiFi Safe?”.

My non-medically-trained mind more-or-less translated this as “Our results provide evidence that Wi-Fi radiation at the 2.4 GHz frequency degrades the fat-soluble energy reserves in mice placenta cell membranes, thereby increasing these cells’ oxidative stress and programmed cell death, at least partly due to over-expression by damaged genes.” [8][9] [10] [11] [12]

Even if my translation isn’t entirely accurate, it seemed to me that the placentas were rendered incapable of properly supporting unborn mice development.

In addition to frequency, the second and third factors in an individual’s total wireless radiation exposures are power density (the intensity of the wireless radiation that reaches the person) and the total duration of such exposures.

Power density drops off quickly with increasing distance from the wireless source; so, as we like to say with regard to wireless devices in general, “distance is our friend.” Wireless hearing aids communicate with each other through the head. The radiation power densities we measured by holding Hub’s hearing aids a heads’ width apart weren’t high, but inside Hub’s head they would be constant and unchanging, because Hub couldn’t move away from them.

As for duration of exposure, unlike Bluetooth headphones that people generally use for short periods, people generally wear their hearing aids 16 hours per day, every day.

So maybe all this information had me a little freaked out. I understand that the United States’ Federal Communications Commission (FCC) bases its rules for wireless radiation transmissions on their heating effect, called SAR (for Specific Absorption Rate). SAR measures how much heat is absorbed by a mannequin’s head filled with liquid.

I figured that heat due to a wireless hearing aid had to be much less than from a microwave oven. But, has this SAR standard been shown to be sufficient to guarantee human safety?

According to the non-profit Environmental Health Trust, “The SAR test dummy is based upon a large adult male (6’2” tall and 220 pounds) called the Specific Anthropomorphic Mannequin, or SAM. 97% of the population is smaller than the SAM model…. Research confirms that radiation absorption into a child’s head can be over two times greater, and absorption into the skull’s bone marrow can be ten times greater than adults.” [13] [This article explains why children are more vulnerable.]

Hub’s Saga Part Three

At our next appointment, we explained what had happened. The specialist told us we were the only people who had asked to have the wireless function turned off. Since that hadn’t worked, he suggested that he enable the airplane mode function. As with a cell phone, this function would deactivate the wireless setting each time it was requested. After performing the proper steps to accomplish this, he seemed confused. But he showed Hub how to activate the airplane mode each time he turned the hearing aids on.

We went on our way, hugely relieved, at least until we met up with our friend and her super- meter. Once again, her meter started beeping when Hub was nearby. Again, mine did not.

This time, Hub called tech support himself. Tech support told him that both he and the hearing aid specialist had done all the right things to activate airplane mode. Were the hearing aids broken? Back to the hearing aid specialist. He took the hearing aids away and told us he’d get back to us when he had an answer.

The Search for Research

I asked pubmed.gov [14] specifically, and the internet generally, about “wireless hearing aid SAR testing.”

PubMed provided references, but the ones I scanned didn’t seem to address the kind of research I was seeking.

The internet matches included one promising title: “Do Wireless Hearing Aids Present a Health Risk?” [15]. The article was subtitled “The facts about electromagnetic radiation and wireless hearing aid technology.” [15] The facts presented were accurate, and they supported my instinct that the SAR heating effect allowed for hearing aids is much less than for microwave ovens. These might have reassured me, except for three things:

(1) The 2017 article didn’t answer my question about whether this SAR standard is sufficient to guarantee human safety. It wasn’t published in a scientific journal, and its copyright is held by a for-profit company [15] that provides “Advanced Healthcare & Technology Tools.” [16].

(2) The article’s information seemed outdated and incomplete. For example:

• The article cited an epidemiological study on “the effects of cellphone use on glioma risk” [15] that was published in 2012,. It hadn’t been updated for a 2018 study [17] that reported a higher incidence rate.

• The article stated that the World Health Organization (in 2006) and the United States’ Federal Communications Commission (FCC) (in 2016) would both “continue to monitor and
promote research relating to the possible health impacts that might result from non-ionizing RF radiation.” [15] I am not aware that any such monitoring or research has occurred.

• According to the article, “By design, hearing aids radiate extremely low levels of energy; therefore, the levels of electromagnetic energy that wireless hearing aids radiate are well below the maximum levels permitted by governing regulations.” [15]. In fact, “The amount of electromagnetic radiation absorbed from wireless hearing aids is anywhere between 80 to 2,000 times less than what regulations would allow….”

The reason the third argument didn’t impress me is a 2004 pilot study of firefighters that was mentioned in an 2013 affidavit to the FCC. [18] This document described firefighters’ “profound neurological symptoms following activation of [two nearby cell] towers in 1999.” [18]

The firefighters’ neurological functioning was tested “objectively using T.O.V.A. testing [Test of Variables of Attention]” [17] and by “SPECT [single-photon emission computed tomography] scans of the brain.” [18] Both tests showed “abnormal” results for all the firefighters in the study. Upon later follow-up, “all [the] firefighters report[ed] profound memory loss.” [18]

An unexpected result from the SPECT scans was “a pervasive, hyper-excitability of the neurons which suggested the exposure to RF (microwave) radiation was causing the neurons to continually fire, without rest. RF radiation appeared to act as a constant stimulant even when the men were away from the station, and in repose.” [18]

This had occurred even though “The emissions from [the nearby cell] towers were measured at approximately 1/1000th to 1/500th of the FCC’s allowable limit. ‘Hot spots’ of reflected radiation were measured at 15 and 30 uW/cm2, yet these “hot spots” were still a fraction of what the FCC allows.” [18]

(3) The comments published below the article were intriguing.

One person wrote, “I think that the neurotransmitter triggers are affected, and sustained use of connectivity may permanently impair neuro-stimulation within the cochlea.” [15]

A second reader replied, “Interesting. I have been trying new … wireless aides for a month. Usually, I can get by, free of aides, in the morning with my family. Today, I was unable to hear them at all.” [15]

A third individual wrote, “There’s a more important question than ‘does your hearing device COMPLY with Gov[ernmen]t Regulations?’ and that is ‘does your hearing aid in fact produce the actual radiation that is CAUSING your new-felt headaches?’” [15]

Another person cited three studies [19] showing “research evidence indicating damage to the auditory system from use of wireless phones,” adding, “There is also research evidence that even small amounts of RF such as from hearing aids can impact the brain.” [15] This writer added, “There is a list of research on this at https://ehtrust.org/science/research-on-wireless-health-effects/ [20] .” [15]

A fifth commenter had a question: “I was wondering if I were to use the blue- tooth compatible hearing aids and turned that part off and just used the device working from the batteries, would that emit fewer EMF’s while still enabling my hearing?” [15] I’ll let Hub answer that one.

Hub’s Saga Part Four

Hub and I adjusted to life without hearing aids. When I wanted to tell Hub something, I sought him out, then faced him before I spoke. In return, Hub got better at verbally confirming what he thought I’d said. We communicated with lightness and laughter – joyful sounds that we hadn’t realized had gone missing. Then, we got a call: Could we meet the specialist later that day?

The specialist had spent his time investigating. When he asked tech support to follow the airplane-mode-protocol they had laid out for him, they also encountered Hub’s problem. Eventually, it was the specialist who found one person within the company who knew the proper procedure and shared it with everyone else.

The specialist handed Hub hearing aids correctly adjusted to airplane mode, and he instructed Hub on how to re-activate this feature before each use.

Here’s Hub’s answer to the question asked above: With airplane mode activated, he can hear nearly as well as he did with the wireless functions. In addition, now when he holds his hearing aids together in his hand, they don’t squeal. When I bring my meter towards his palm, it also stays silent. Whew!

Summing Up and Moving On

Why hadn't the hearing aid company tested its procedures and reviewed its specialist and patient manuals before marketing Hub’s hearing aids? Possibly it’s simply because nobody thought to do so. No such testing or pre-marketing reporting is required by the Federal Communications Commission.

As for the rest of us, we can be proactive, by applying the six steps that follow:

1# Practice Self Care

Until more is known, we can ask our hearing aid specialists to enable the airplane mode function on our wireless hearing aids and to train us in its use. We can encourage those we care about to do the same.

In addition, we can purchase a radio frequency radiation meter (most include the 2.4-2.48 GHz frequency range). Such meters measure radiation power density from wireless devices in our environment, allowing us to become aware of our exposures. (View this article on choosing a good EMF Meter)

2# Educate

Regarding microwave ovens: By 2013, several medical researchers and doctors were concerned about the number of small children who needed treatment for “microwave-related burns.” [21] By asking questions, they determined that these children’s severe burns occurred “while retrieving heated food and liquids from microwave ovens.” [21] The medical professionals reasoned that it would help matters if microwave ovens were made “more difficult for small children to open.” [21] To follow up, they proposed that Underwriters Laboratories “update … UL 923, the Standard for Microwave Cooking Appliances.” [21]

In 2014, an Underwriters Laboratories’ Standards Technical Panel (STP), composed “of stakeholders from various interest groups, including government agencies, consumer reporting groups, consumers, manufacturers and supply chain companies” [21], reviewed the proposal but “did not reach [the] consensus” [21] required to proceed.

However, In 2016, medical researchers published “a report on national estimates of microwave- related burn injuries among young children” [21].

In 2017, a national task force was formed.

In 2018, the task force submitted a new proposal to Underwriters Laboratories, one that addressed concerns “such as the need to ensure that a childproof design would not present an issue for elderly or disabled users.” [21]

Underwriters Laboratories’ STP accepted the new proposal that year.

As a result, updated UL-923 standards will take effect in 2023.

3# Develop Perspective

In 2021, we don’t hear much about children’s scalds from handling microwaved food. That’s probably because microwave oven manufacturers didn’t have to wait until 2023 to begin making safer microwave ovens.

One lesson here is how the scientific method takes time. In this case, an initial observation period (of children’s burns) was followed by a hypothesis period as to possible cause (easily- opened microwave oven doors), then a research period (gathering information on numbers of “microwave-related burn injuries” [21]), and a peer review period prior to publication.

A second lesson is how additional action, based on science, was necessary for create change. For UL-923, that change happened within two years.

My initial question was, “Could the newer digital wireless hearing aids improve hearing but also provide a stressor that could contribute to brain disorders such as Alzheimer’s and Parkinson’s?”

All I could determine was that hearing aid sales, hearing aid usage, and various Parkinson’s and Alzheimer’s statistics all have increased over the past several years. I couldn’t find data or studies that would tie these increases together. If anyone reading this knows of them, I’d be thrilled to hear! Otherwise, let’s…

4# Advocate for Safety and Common Sense

There’s nothing to prevent independent researchers or even the FCC from paying attention, not just to what the engineers who set ISM band standards in1985 knew about how wirelessheating works, but to the work of medical scientists who have been working since that time to determine how wireless heating and/or other qualities affect people.

We can advocate that researchers investigate, to find out if wireless hearing aids could be a risk factor for Parkinson’s and Alzheimer’s diagnoses and disease outcomes.

In the United States, there’s one agency that potentially could make researchers’ job easier. This agency both sells a lot of hearing aids and manages a lot of health information for its clients. It’s the U S Department of Veterans Affairs. [22]

Can we agree that our veterans, like our firefighters, are important First Responders?

As the firefighters’ test results illustrate, it’s important to know not just how things work (that’s physics), but also how things work on people and other living things (that’s biology). [18]

5# Support Solutions

In addition to new epidemiological research of U S veterans and/or others, one additional way to learn about possible harmful biological effects from wireless radiation would be to require that wireless devices be tested for safety using biological tools such as the SPECT and other new technologies that directly measure biological effects.

I have just two new questions:

(1) Is there anyone out there who is interested in pursuing epidemiological research regarding my initial question, possibly with the cooperation of the Department of Veterans Affairs?
And,
(2) is there anyone out there who is interested in pursuing testing of biological effects from wireless devices?

Underwriters Laboratories is a non-profit organization. Its tag lines are, “Dedicated to Safety”, “Guided by Science.” [23]

For anyone interested in learning more, Underwriters Laboratories has a “contact us” link. [23]

6# Create Change

About the time those many years ago when Hub caught that bus and others boarded a flight to Vietnam, airways in both places broadcast “500 Miles,” a song originally by Hedy West. This time around, the song’s musicians were a trio, called Peter, Paul and Mary.

More than three decades later, that same Mary wrote these lyrics:

“Ah, you know I’ve always loved you
And I know you’ve loved me too
So it’s hard to watch you crumble
And forget all that you knew…

“Memory moves us past each other
Time is a ribbon without an end
Love is the lesson we keep learning
Death but a moment we must spend.” [24]

To create change, we too must “keep learning.” And, for us as well as for Mary, “Love is the lesson” that motivates our efforts.

Many thanks to Diane Craig for this guest post.

For more than 30 years, Diane Craig has advocated for persons diagnosed with celiac disease. From 2013 to 2018, among other activities as a board member for the California non-profit Celiac Support Group, she helped draft a petition to the FDA to label gluten in drugs and wrote blog posts to help publicize research regarding the then-new concept of Non-Celiac Gluten Sensitivity.

Sources and Bibliography

[ 1] Published by J El!ein, Percentage of U.S. adults who thought the following were the most unpleasant ways to die as of 2019. Statistica, 4-9-2020. At https://www.statista.com/statistics/1108969/unpleasant-ways-to-die-us-adults-opinion/. Accessed May 5, 2021.

[2] American Parkinson Disease Association. Death in Parkinson’s Disease. No date. At https://www.apdaparkinson.org/article/death-parkinsons-disease/. Accessed May 1, 2021.

[3] The Silver Book. Silver Book Fact: Parkinson’s disease is the 14th leading cause of death in the U.S. Note: I had downloaded this 2014 reference as a pdf, but the content at https://www.silverbook.org/publication/silver-book-parkinsons-disease-fact-sheet/ had been updated to 2019 when I tried to access it again, on May 11, 2021.

[4] JAMA, JAMA Network. The Leading Causes of Death in the US for 2020. 3-31-2021. At https://jamanetwork.com/journals/jama/fullarticle/2778234. Accessed May 11, 2021. JAMA is the Journal of the American Medical Association.

[5] Name has been changed.

[6] I accessed a number of sources for this section of my article.

[7] H Vafaei, G Kavari, H R Izadi, Z Z Dorahi, Mi Dianatpour, A Daneshparvar, and I Jamhiri. Wi-Fi (2.4 GHz) affects anti-oxidant capacity, DNA repair genes expression and, apoptosis in pregnant mouse placenta. Iran J Basic Med Sci. 2020 Jun; 23(6): 833–840. At https://pubmed.ncbi.nlm.nih.gov/32695301/. Accessed May 1, 2021.

[8] Lipids are “Organic compounds not soluble in water, but soluble in fat solvents such as alcohol. Lipids are stored in the body as energy reserves and are also important components of cell membranes.” Citation: Lipids. (n.d.) Gale Encyclopedia of Medicine. (2008). Retrieved May 12 2021 from https://medical-dictionary.thefreedictionary.com/Lipids.

[9] Peroxidation is “a type of reaction in which oxygen atoms are formed leading to the production of peroxides. It is stimulated in the body by certain toxins and infections.” Citation: Peroxidation. (n.d.) Collins English Dictionary – Complete and Unabridged, 12th Edition 2014. (1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014). Retrieved May 12 2021 from https://www.thefreedictionary.com/peroxidation.

[10] Apoptosis is “A natural process of self-destruction by degradative enzymes in certain cells, such as epithelial cells and erythrocytes, that are genetically programmed to have a limited lifespan or are damaged, as by irradiation or toxic drugs. Also called programmed cell death.” Citation: Apoptosis. apoptosis. (n.d.) American Heritage® Dictionary of the English Language, Fifth Edition. (2011). Retrieved May 12 2021 from https://www.thefreedictionary.com/apoptosis.

[11] CDKN1A is “A gene on chromosome 6p21.2 that encodes a cyclin-dependent kinase inhibitor, which binds to and inhibits the activity of cyclin-CDK2 or -CDK4 complexes, thus acting as a regulator of cell cycle progression at G1. CDKN1A expression is controlled by p53, a tumour suppressor that mediates p53-dependent cell cycle G1-phase arrest in response to various stress stimuli. CDKN1A is specifically cleaved by CASP3-like caspases, activating CDK2 and possibly also the apoptosis pathway.” Citation: CDKN1A. (n.d.) Segen's Medical Dictionary. (2011). Retrieved May 12 2021 from https://medical-dictionary.thefreedictionary.com/CDKN1A.

[12] GADD45A is “A gene on chromosome 1p31.2 that is upregulated in response to stressful growth-arrest conditions and exposure to DNA-damaging agents. The encoded protein activates the p38/JNK pathway via MTK1/MEKK4 kinase.” Citation: GADD45A. (n.d.) Segen's Medical Dictionary. (2011). Retrieved May 12 2021 from https://medical-dictionary.thefreedictionary.com/GADD45A.

[13 ] Environmental Health Trust. The SAR Test Is Inadequate. July 13, 2017. At https://ehtrust.org/sar-test-inadequate/. Accessed May 16, 2021.

[14] The United States’ National Library of Medicine is part of the National Institutes of Health It contains “citations for biomedical literature from MEDLINE, life science journals, and online books”, at pubmed.gov or https://pubmed.ncbi.nlm.nih.gov. Accessed May 14, 2021.

[15] J R Burwinkel, AuD; W J Mitchell, MSEE; E Elghannai, PhD; and J A Galster, PhD. Do Wireless Hearing Aids Present a Health Risk – Hearing Review: The facts about electromagnetic radiation and wireless hearing aid technology. Hearing Review, June 6 2017. At https://www.hearingreview.com/inside-hearing/research/wireless-hearing-aids-present-health-risk. Accessed May 14, 2021.

[16] At https://medqor.com. Accessed April 14, 2021.

[17] A Philips, D L Henshaw, G Lamburn and M J. O’Carroll. Brain Tumours: Rise in Glioblastoma Multiforme Incidence in England 1995–2015 Suggests an Adverse Environmental or Lifestyle Factor. Hindawi Journal of Environmental and Public Health, Volume 2018, Article ID 7910754, June 24 2018. At https://doi.org/10.1155/2018/7910754. Accessed April 11, 2021.

[18] S D Foster, MSW. Comment Filed Before the Federal Communications Commission, FCC 13-39, ET Docket Numbers 13-84 (Reassessment of Federal Communications Commission Radiofrequency Exposure Limits and Policies) and 03-137 (Proposed Changes in the Commission’s Rules Regarding Human Exposure to Radiofrequency Electromagnetic Fields). September 2, 2013.

[19] The studies were:
(1) Medeiros, Luisa Nascimento and Tanit Ganz. “Tinnitus and cell phones: the role of electromagnetic radio frequency radiation.” Brazilian Journal of Otorhinolaryngology, vol. 82, no. 1 2015, 97-104.
(2) Özgür A, et al. “Effects of chronic exposure to electromagnetic waves on the auditory system.” Acta Otolaryngol, vol. 135, no. 8, 2015, pp. 765-70.
(3) Seckin E, et al. “The effect of radiofrequency radiation generated by a Global System for Mobile Communications source on cochlear development in a rat model.” Journal of Laryngology and Otology, vol. 128, no. 5, 2014, pp. 400-5.

[20] This 2018 link still links to hearing studies. Accessed May 15, 2021.

[21] Underwriters Laboratories Standards. Partnering to Help Reduce Microwave-Related Scald Injuries on Small Children. No date. At https://ul.org/focus-areas/standards/partnering-help-reduce-microwave-related-scald-injuries-small-children. Accessed May 16, 2021.

[22] The website for the U S Department of Veterans Affairs is https://www.va.gov.

[23] Underwriters Laboratories’ website Home Page and About link are both At https://ul.org. Accessed May 16, 2021.

[24] M Travers, But A Moment. copyright 1995. In Liner Notes for PP&M LifeLines Album, Warner Bros. Records, Inc, ©1995. Also online At https://www.azlyrics.com/lyrics/peterpaulandmary/butamoment.html. Accessed May 13, 2021.