What is an NRR?

NRR is an acronym that stands for Noise Reduction Rating. The government, through the Environmental Protection Agency, now requires that anti-noise hearing protection devices carry a label showing the NRR. This means that, if you wear a product with an NRR of 29, for example, in accordance with its directions, the noise entering your ears will be reduced by 29 decibels.

Do earmuffs offer better hearing protection than earplugs?

No. A well-designed earplug can offer hearing protection comparable to or exceeding that of earmuffs at most frequencies. More important is evaluating the individual devices and the users compliance with the proper use of the device.

Is it possible that my ears can get used to the noise that causes hearing loss?

No. If your ears seem to get used to the noise, it is only an effect caused by the deafening of your ears. Ears do not “toughen up” with repeated exposure to noise. Mack’s hearing protection devices can prevent this loss in quality of life from occurring.

I’ve already lost some or most of my hearing; why should I wear hearing protection?

The existence of full or partial hearing loss does not protect one from further hearing loss due to noise exposure. While hearing loss is permanent in nature and the use of hearing protection devices cannot restore hearing loss, they can help prevent further damage. The proper use of hearing protection devices can also help prevent temporary hearing losses, and allow existing temporary losses to recover before they become permanent.

Is there any hearing protection on the market that block out 100% of the noise?

The highest noise reduction rating (NRR) currently offered by an earplug is around 33 decibels. Decibel levels up to the earplug’s NRR rating will be blocked out entirely. Any noise over the earplug’s NRR may be heard. Another important factor to note is that the body absorbs sound; so short of encapsulating oneself in a sound proof chamber, it is seemingly impossible to block out all noise. Earplugs and other types of hearing protection devices are designed to lessen the harshness of the noise and bring it down to a safer, more tolerable level.

How can I tell when a noise is potentially damaging to my hearing?

People differ in their sensitivity to noise. As a general rule, if you have to shout to communicate with a normally hearing person at a distance of about three feet, the noise is potentially harmful. Other signs to watch for are if the noise hurts your ears, causes your ears to ring, or causes temporary hearing loss for up to several hours after exposure. As the figure below illustrates, the start of unsafe levels begins at approximately 85 decibels. It is important to note that it is not only the level of noise, but also the duration of exposure, that determines whether it is a minor irritant, a definite disturbance, or a threat to your hearing.

.......................

Noise Level Decibels Chart – A Comprehensive Guide

April 26, 2024

By Mounika D

In the last decade, we have seen an increased concern with the quality of the environment, especially due to air, water, and noise pollution. Any displeasing sound that is created by humans, animals, and machines is the cause of Noise Pollution. Continuous exposure to noise above a threshold can cause severe ear pain or even permanent hearing loss in humans as well as animals. But what noise levels are safe? In this guide, let us understand the basics of Noise. We will also see how to measure noise. After that, we will take a look at a Noise Level Decibels Chart with the noise made by everyday objects.

A Brief Note on Sound

Before understanding Noise, we need to first know a little bit about Sound. After all, Noise is nothing but unwanted Sound. The ‘Sound’ we hear is the result of pressure variation in the air or any medium.

When a source induces vibrations in the air, it is actually producing an alternating band of dense and sparse particles of air. The movement of air particles will result in a fluctuation of atmospheric pressure.

Our ear detects these pressure fluctuations happening above and below the atmospheric pressure and creates the sensation of hearing.

Sound is a form of energy produced by longitudinal mechanical waves in solids, liquids, or gases. We need a source or vibrating object to transmit sound waves. These sound waves travel through a medium. Finally, we need a receiver, an ear in our case, to absorb the energy.

What is Noise?

As we already mentioned before, any unwanted sound is Noise. Here, the term ‘unwanted’ means that it has adverse health effects on human and animal hearing.

We can also define Noise as a sound that interferes with speech and hearing. In terms of public health concerns, noise is a sound that has enough intensity to cause hearing damage

The meaning of noise can be subjective. One person may enjoy listening to heavy metal music at one volume. But the same music at the same volume may be noise to another person.

There are many sources of Noise. Household works and chores, transportation, and construction are some noises everyone encounters frequently. If you live near or work in an industrial area, then there are several sources of noise there. Machines, motors, tools, etc. all create noise.

Effects of Noise

On Human Health

Noise Pollution is the latest category of environmental pollutants (the other being air and water). Several institutions and organizations have formally recognized noise as a threat to the health and well-being of humans. Hearing loss is the first and most important effect of noise.

Apart from physiological health, noise also affects the psychological behaviour of humans. Continuous exposure to severe levels of noise can cause hypertension, stress, irregular sleep patterns, etc.

On Environment

Noise also has a harmful effect on animal life. Overexposure to noise can lead to temporary or permanent hearing loss in many animals. Noise can also cause stress and disturbs the balance of predator – prey detection.

An impact of noise on animals is an increased risk of untimely death. You might have seen the news about the death of whales due to exposure to military sonar.

How Do We Measure Noise?

Before looking at the Noise Level Decibels Chart, we need to first understand how we measure Sound or Noise.

We know that a vibrating source alternately rises and drops the pressure of air particles with respect to atmospheric pressure. This variation in the pressure of the medium (air) above and below the atmospheric pressure is known as Sound Pressure.

The SI units of pressure are pascals (Pa) or Newton per meter square (N/m2). The human ear can detect sound pressures in the range of 20µPa all the way over 200Pa.

Two important points to note here. The range of sound pressure that can be produced is huge from 0.00002Pa to 1000Pa. The second point is the response of the human ear to an increase in sound pressure is not linear.

Hence, we measure sound using the decibel scale. Sound Pressure Level or SPL is the sound or noise measurement expressed as a logarithmic ratio of sound pressure to a reference sound pressure. This logarithmic ratio is the dimensionless unit of Power, the decibel (dB).

SPL = 20 log (p / pref) decibels (dB).

Here, ‘p’ is the root mean square value of the sound pressure in Pa (or N/m2). The reference sound pressure is 0.00002Pa or 2 × 10-5 N/m2.

A common way to represent sound pressure is dBA. This is a weighted Sound Pressure Level adjusted to the human sensitivity of the human ear.

 The following table shows the relationship between Sound Pressure Level in dB and Sound Pressure in Pa.

Noise has a major impact on sleep. Exposure to too much noise during sleep has immediate effects while we are sleeping, which leads to short-term issues the next day, and over time may result in long-term mental and physical consequences.

Short-Term Effects of Noise

Getting sufficient undisturbed sleep is critical for feeling good and performing well. Although you are unlikely to notice subtle changes to your sleep structure and biochemical experience of sleep, these changes can manifest the next day in ways that are more pronounced. Sleepiness, irritability, and poorer mental health are associated with exposure to nighttime noise the night before.

Poor quality sleep over a long period of time is linked with high blood pressure, heart disease, weight gain, type 2 diabetes, and certain types of cancer. The relationship between noise during sleep and long-term health effects is less clear, but studies indicate a possible association with high blood pressure and decreased overall health.

“A quiet space is an essential component of an environment that is conducive to sleep. I always try to get a detailed description of my patient’s sleep environment so we can identify any factors that might be creating disruptive noise.”

Dr. David Rosen, Sleep Medicine Physician

Is It Better to Sleep in Silence or With Noise?

In a perfect world, we would all have the option to retreat to a completely soundproof bedroom. However, noise exposure is a nightly reality for most.

You might be able to limit sound exposure in your bedroom at night by following the steps outlined above, but if that’s not enough, adding a consistent background noise may mask or drown out the sounds you can’t control and could help to counteract the harmful effects of noise exposure during sleep. Also, some people find that background noise helps to distract them from anxious or intrusive thoughts and prepares the mind for sleep.

Research studies have produced conflicting data about whether adding a stream of background noise improves sleep quality. One study of the effects of adding sound from an air conditioner in the home found no positive impact on sleep. In another experiment, researchers investigated the effect of broadcasting white noise into the rooms of hospitalized patients and found that white noise improved sleep quality

over the course of three nights compared to a control group. A third study of patients who were having trouble sleeping showed that white noise helped them fall asleep 38% more quickly. Given the inconsistent data, the utility of adding background noise may come down to personal preference.

What Are the Best Sounds to Sleep To?

The best night sounds for sleeping can vary from one person to the next, but consider utilizing sounds that are loud enough to cover other noises and that maintain an even tone and volume; sudden sound changes could cause you to wake up. It might help to experiment with a few and see what works for you. Here are some ideas to get you started:

White noise

White noise is produced by layering multiple sound frequencies at the same time. One option is to invest in a white noise machine; you could also look into downloading a white noise app or sound file to your smartphone or tablet. If white noise sounds too harsh, then you may prefer pink noise instead. Pink noise combines louder high-frequency noise with softer low-frequency noise, resulting in a sound that is more even and less layered.

Turn on a fan or air conditioner

These devices produce consistent ambient noise that may help to drown out intrusive environmental sounds.

Music

The songs that are soothing and sleep-inducing depend on one’s own musical taste and personal experience with music. You might try creating a playlist of songs that are relaxing to you or searching for curated sleep playlists provided by streaming services.

Sounds from nature

Hearing rain, ocean waves, wind, and other natural sounds helps some people fall asleep. Certain sleep sound machines come programmed with a selection of sounds to choose from, or you can search for apps or sound files to download onto your device. A variety of sleep sounds can also be found on our YouTube channel.

How To Avoid Noises When Trying to Sleep

In a city, it’s common to deal with the sounds of traffic, sirens, airplanes, or people gathering outside. Even in suburban or rural settings you are unlikely to be completely isolated from noisy appliances, cars, neighbors, and animals during the night. Additionally, other people or pets in your home may make noise that disrupts your sleep. Think about the specific sounds that affect your living space as you review the following ideas for avoiding noise at night.

Adjust Your Bedroom Environment

Creating a bedroom space that’s as supportive of a quiet night’s sleep as possible is a critical part of good sleep hygiene.

Add soft surfaces

Sound reverberates off of hard surfaces and is absorbed by soft ones. Adding rugs, cushioned furniture, or thick curtains to your bedroom might help block or lessen noise both coming in from the street and from within your house.

Insulate windows

If loud noises are infiltrating your bedroom from the outside, options include installing soundproof windows as well as sealing any air gaps in the windows you have.

Reduce appliance noise

If your refrigerator or air conditioner is emitting abnormal sounds, have it repaired. When the time comes to replace an appliance, shop for one that is quiet.

Turn off alerts

Make sure you have your electronic devices on silent mode so that notifications don’t wake you up at night.

“For those struggling with a noisy sleep environment, be prepared for some trial and error. For example, you might find ear plugs to be helpful at first, but over time you may find you prefer the noise of a fan. Go into this with an open mind and you can find the right solution, because you deserve a restful and quiet sleep environment.”

Dr. David Rosen, Sleep Medicine Physician

Plug Your Ears

Depending on your living situation, you may not be able to physically soundproof your bedroom. Ear plugs are an effective tool as long as they don’t interfere with your ability to sleep.

A research study found that hospital patients who wore earplugs and an eye mask woke up less often and experienced more deep sleep compared to a group of patients who did not.

An alternative to earplugs is to find small, comfortable noise-cancelling headphones, which are designed to block out noise and also allow you to introduce relaxing sounds that could help you sleep.

Negotiate With Others

If your primary source of noise at night is coming from other people in your home, communicate with them about how they can help you get the sleep you need and how you can return the favor. When operating on different sleep schedules, some noise at night is inevitable, but you could try agreeing upon rules for quiet hours. For example, it might help to request that your partner or roommate use headphones to listen to TV or music while you are sleeping. Planning ahead by cooking meals and laying out the next day’s clothes during waking hours can also cut down on disruption.

If your partner’s snoring is keeping you up, talk with them about it. Lifestyle changes or anti-snoring mouthpieces might help. Very loud snoring and choking or gasping sounds at night could be signs of obstructive sleep apnea. Seek a doctor’s help if you notice these symptoms in your partner.

About Our Editorial Team

Written By

Jay Summer, Staff Writer

Jay Summer is a health content writer and editor. She holds a B.S. in psychology and master's degrees in writing and public policy.

Medically Reviewed by

Dr. Abhinav Singh, Sleep Medicine Physician MD

Dr. Singh is the Medical Director of the Indiana Sleep Center. His research and clinical practice focuses on the entire myriad of sleep disorders.

References

12 Sources