What is noise-induced hearing loss?

Every day, we experience sound in our environment, such as the sounds from television and radio, household appliances, and traffic. Normally, these sounds are at safe levels that don’t damage our hearing. But sounds can be harmful when they are too loud, even for a brief time, or when they are both loud and long-lasting. These sounds can damage sensitive structures in the inner ear and cause noise-induced hearing loss (NIHL).

NIHL can be immediate or it can take a long time to be noticeable. It can be temporary or permanent, and it can affect one ear or both ears. Even if you can’t tell that you are damaging your hearing, you could have trouble hearing in the future, such as not being able to understand other people when they talk, especially on the phone or in a noisy room. Regardless of how it might affect you, one thing is certain: noise-induced hearing loss is something you can prevent.

Who is affected by NIHL?

Exposure to harmful noise can happen at any age. People of all ages, including children, teens, young adults, and older people, can develop NIHL. Based on a 2011-2012 CDC study involving hearing tests and interviews with participants, at least 10 million adults (6 percent) in the U.S. under age 70—and perhaps as many as 40 million adults (24 percent)—have features of their hearing test that suggest hearing loss in one or both ears from exposure to loud noise. Researchers have also estimated that as many as 17 percent of teens (ages 12 to 19) have features of their hearing test suggestive of NIHL in one or both ears (Pediatrics 2011(link is external)), based on data from 2005-2006.

What causes NIHL?

NIHL can be caused by a one-time exposure to an intense “impulse” sound, such as an explosion, or by continuous exposure to loud sounds over an extended period of time, such as noise generated in a woodworking shop.

Recreational activities that can put you at risk for NIHL include target shooting and hunting, snowmobile riding, listening to MP3 players at high volume through earbuds or headphones, playing in a band, and attending loud concerts. Harmful noises at home may come from sources including lawnmowers, leaf blowers, and woodworking tools.

Sound is measured in units called decibels. Sounds of less than 75 decibels, even after long exposure, are unlikely to cause hearing loss. However, long or repeated exposure to sounds at or above 85 decibels can cause hearing loss. The louder the sound, the shorter the amount of time it takes for NIHL to happen.

Here are the average decibel ratings of some familiar sounds:

• The humming of a refrigerator
  45 decibels
• Normal conversation
  60 decibels
• Noise from heavy city traffic
  85 decibels
• Motorcyles
  95 decibels
• An MP3 player at maximum volume
  105 decibels
• Sirens
  120 decibels
• Firecrackers and firearms
  150 decibels

Your distance from the source of the sound and the length of time you are exposed to the sound are also important factors in protecting your hearing. A good rule of thumb is to avoid noises that are too loud, too close, or last too long.

Credit: NIH Medical Arts

How can noise damage our hearing?

To understand how loud noises can damage our hearing, we have to understand how we hear. Hearing depends on a series of events that change sound waves in the air into electrical signals. Our auditory nerve then carries these signals to the brain through a complex series of steps.

1. Sound waves enter the outer ear and travel through a narrow passageway called the ear canal, which leads to the eardrum.
2. The eardrum vibrates from the incoming sound waves and sends these vibrations to three tiny bones in the middle ear. These bones are called the malleus, incus, and stapes.
3. The bones in the middle ear couple the sound vibrations from the air to fluid vibrations in the cochlea of the inner ear, which is shaped like a snail and filled with fluid. An elastic partition runs from the beginning to the end of the cochlea, splitting it into an upper and lower part. This partition is called the basilar membrane because it serves as the base, or ground floor, on which key hearing structures sit.
4. Once the vibrations cause the fluid inside the cochlea to ripple, a traveling wave forms along the basilar membrane. Hair cells—sensory cells sitting on top of the basilar membrane—ride the wave.
5. As the hair cells move up and down, microscopic hair-like projections (known as stereocilia) that perch on top of the hair cells bump against an overlying structure and bend. Bending causes pore-like channels, which are at the tips of the stereocilia, to open up. When that happens, chemicals rush into the cell, creating an electrical signal.
6. The auditory nerve carries this electrical signal to the brain, which translates it into a sound that we recognize and understand.

Stereocilia perch atop sensory hair cells in the inner ear
Credit: Yoshiyuki Kawashima

Most NIHL is caused by the damage and eventual death of these hair cells. Unlike bird and amphibian hair cells, human hair cells don’t grow back. They are gone for good.

What are the effects and signs of NIHL?

When you are exposed to loud noise over a long period of time, you may slowly start to lose your hearing. Because the damage from noise exposure is usually gradual, you might not notice it, or you might ignore the signs of hearing loss until they become more pronounced. Over time, sounds may become distorted or muffled, and you might find it difficult to understand other people when they talk or have to turn up the volume on the television. The damage from NIHL, combined with aging, can lead to hearing loss severe enough that you need hearing aids to magnify the sounds around you to help you hear, communicate, and participate more fully in daily activities.

NIHL can also be caused by extremely loud bursts of sound, such as gunshots or explosions, which can rupture the eardrum or damage the bones in the middle ear. This kind of NIHL can be immediate and permanent.

Loud noise exposure can also cause tinnitus—a ringing, buzzing, or roaring in the ears or head. Tinnitus may subside over time, but can sometimes continue constantly or occasionally throughout a person’s life. Hearing loss and tinnitus can occur in one or both ears.

Sometimes exposure to impulse or continuous loud noise causes a temporary hearing loss that disappears 16 to 48 hours later. Recent research suggests, however, that although the loss of hearing seems to disappear, there may be residual long-term damage to your hearing.

Can NIHL be prevented?

NIHL is the only type of hearing loss that is completely preventable. If you understand the hazards of noise and how to practice good hearing health, you can protect your hearing for life. Here’s how:

• Know which noises can cause damage (those at or above 85 decibels).
• Wear earplugs or other protective devices when involved in a loud activity (activity-specific earplugs and earmuffs are available at hardware and sporting goods stores).
• If you can’t reduce the noise or protect yourself from it, move away from it.
• Be alert to hazardous noises in the environment.
• Protect the ears of children who are too young to protect their own.
• Make family, friends, and colleagues aware of the hazards of noise.
• Have your hearing tested if you think you might have hearing loss.

What research is being done on NIHL?

The National Institute on Deafness and Other Communication Disorders (NIDCD) supports research on the causes, diagnosis, treatment, and prevention of hearing loss. NIDCD-supported researchers have helped to identify some of the many genes important for hair-cell development and function and are using this knowledge to explore new treatments for hearing loss.

Researchers are also looking at the protective properties of supporting cells in the inner ear, which appear to be capable of lessening the damage to sensory hair cells upon exposure to noise.

The NIDCD sponsors It’s a Noisy Planet. Protect Their Hearing®, a national public education campaign to increase awareness among parents of preteens about the causes and prevention of NIHL. Armed with this information, parents, teachers, school nurses, and other adults can encourage children to adopt healthy hearing habits.

Source NIDCD

Thanks for reading and take care of your ears!

Dust Monitoring Equipment – providing equipment, services and training in dust fallout management to the mining industry.

Some of the answers to this question found on Quora

“This is an excellent question and the answer to it will vary depending on what type of dust you have breathed in.  The truth be told, we all breathe in lots of dust everyday.  Most dust will be filtered out by the hairs and mucus lining in your nose.

However, dust that is inhaled from asbestos or fiberglass is another matter entirely.  In this case, a trip to the hospital is imperative and without delay.  Unfortunately, there is no cure for asbestos being inhaled but doctors may prescribe breathing treatments and medication to help with the symptoms.  This is why companies exist where employees have the equipment and training to remove these materials safely.

Working with wood and drywall can be dangerous because of the dust these material can create.  Always wear a dust mask to prevent dust inhalation.  Extended periods of breathing in the dust will potentially cause lung problems.

That being said if you breathe in too much dust from cleaning a dirty room you may begin to sneeze and/or cough which is your body’s attempt to remove the dust.  If you went beyond what the body can expel by sneezing and/or coughing you usually will experience a sore throat.  When this happens drinking a cool glass of water will help to flush your throat.  Sometimes a cough drop will help the throat to recover faster.

If breathing in a lot of dust around your home is a concern for you why not hire a professional cleaning company to clean your home and let them handle the dust.”

“Healthy lungs constantly make mucus and we constantly clear our airways for precisely this sort of situation: dust particles get trapped in the mucus and we cough it up and out. Of course, we also (usually) breathe through our noses which have tiny hairs in them which clean the air we breathe, trapping a lot of the particulate matter. Our noses also warm and moisturize the air we breathe, which helps particles become caught. Between the two mechanisms, a lot of the air we breathe is substantially cleaner, once it gets to our lungs; if it isn’t, it gets coughed up and out over time. When we smoke, our lungs try mightily to keep up with the amount of nastiness that we inhale, but with the carbon monoxide, the heat, and the tar in cigarettes, they simply can’t keep up, and become damaged. Over time, once one quits smoking, the lungs are able to renew themselves and we cough out a lot of the crap. Probably the best thing you can do after breathing a lot of dust would be to get yourself to the cleanest air you can find, bearing in mind that air-conditioned air is usually cleaner than outside air. Stay there for as long as you can – sleep there, if possible!  There’s really not a lot else you CAN do.”

“Immediately, put all the clothes you were wearing into the wash. Then have a thorough shower, with particular attention to washing your hair. If you feel at all sick or otherwise “unusual”, drink a large glass of milk.

Expect to cough, and encourage it: spit out what you cough up, do not swallow it.

While you are doing all this, think about the dust. If it was from asbestos, any other unidentified building insulant, sawdust, or any insoluble mineral dust such as from mica, stone-cutting, or metallic dust, go to your nearest hospital immediately. If possible, take a sample of the dust with you.

Finally, don’t do it again: a dust mask is cheap, and life isn’t.”

“If you find yourself coughing, let it happen. Drink lots of water/fluid  so that your body can hydrate your secretions well. I think that you  should be able to clear the material in a day or two, if it isn’t too  bad.

The  little hairs in your airways and nose will be busy clearing all the junk  out of your lungs. If you blow your nose and see strange material, it  may be from what you breathed in. The material in your lungs should get  out of your lungs and be swallowed naturally, as normal.”

Dust Monitoring Equipment – providing equipment, services and training in dust fallout management to the mining industry.

Determination of Specific Gravity of Fallout dust Pycnometer method with reference to ASTM D854-2.

1. INTRODUCTION

Specific gravity (Gs) of a solid substance is the ratio of the weight of a given volume of material to the weight of an equal volume of water. In effect, it tells us how much heavier (or lighter) the material is than water. For exact analysis, the specifications require distilled or de-mineralized water.  Soil’s specific gravity largely depends on the density of the minerals making up the individual soil particles.  Two specific gravity readings were obtained from the one sample and the average has been used to provide the specific gravity of the sample.

2. METHODOLOGY

2.1 Apparatus Used for Determining Specific Gravity:

Pycnometer (10millimetre capacity), Mortar and pestle, laboratory Oven, Heat resistant gloves, Stirring spatula, Distilled water, Desiccator, Thermometer. Balance scale sensitive to 0.01 gram

2.2 Sample Preparation.

Fallout dust was oven dried using a laboratory oven for 6 hours. Fallout dust was placed on a desiccator for 60 minutes to cool. Desiccator was used to prevent loss and dilution of fallout dust material. Cooled dried sample materials were broken down using mortar and pestle.

2.3 Determination of Specific Gravity

Specific gravity of the fallout dust was determined in the laboratory using a pycnometer method with reference to ASTM D854-2 using de-ionized water at 20 ⁰C. A 10 ml pycnometer was filled with water to the meniscus and the mass of the pycnometer filled with deionised water was determined denoted by the variable Ma.  Exactly
3.4 ml of water was withdrawn from the pycnometer to make space for the dust, the pycnometer was left with 6.6 ml of water and about 2 g (Mo) of dust was added to the 6.6 ml water in the pycnometer. The pycnometer was closed with 6.6 ml of deionized water and about 2 g of dust was gently rolled on a smooth table for about 10 minutes to remove air bubbles.  Water in the pycnometer was filled to meniscus again while making sure that no dust materials were stuck on the neck of the pycnometer.  Mass of the pycnometer that was filled with water and fallout dust sample (M_b) was recorded after 12 hours of curing.  Specific gravity of the dust samples was computed using the following formula.

 
Gs = ___Mo.K_______
Mo + (Ma – Mb)

Where:       Gs = Specific Gravity

Mo = Mass of Oven Dried fallout dust Materials (g)

K   = Temperature correction factor (of which at 20 ⁰C =1)

Ma = Mass of the pycnometer filled with De-ionized water (g)

Mb = Mass of the pycnometer filled with water and fallout dust sample (g)

Figure 1: apparatus used for determining specific gravity; (A) laboratory oven for drying the fallout dust, (B) Desiccator for cooling the samples, (C) Mortar and pestle for breaking down the dust sample lumps with pycnometers, (D) Mili-Q de-ionised water generator, (E) Scale balance for determining the weight.

3. RESULTS AND DISCUSSION

The results were recorded in a spreadsheet and summarised (Table 1)

Table 1: Specific Gravity of the Samples (Generic Results)

Specific gravity of the dust samples was determined as shown in Table 1.  Specific gravity of the dust sample was found to be 2.72 times that of water.  The fallout dust materials were denser than water.  Since the Specific gravity was determined at 20 ⁰C, the temperature did not have effect on the determined Specific gravity since its correction factor (K) is equal to 1 as supported by the table below:

PHOTO GALLERY.

Pycnometers filled with de-ionised water and fallout dust materials

Lutendo (DustWatch geology consultant) crushing dust using pebble and mortar

DUST MONITORING TRAINING COURSE

DustWatch cc (www.dustwatch.com) is in a battle to combat dust hazards.

In response to that we conduct numerous fallout dust monitoring training courses in Cape Town and Pretoria, South Africa. At the end of the course, trainees receive certificates of recognition to acknowledge the skills they acquired during the training.

Previously DustWatch cc was at Greenmined Environmental – office 36 Baker Square Block One, De Beers Avenuewww.avenuesguesthouse.co.zawww.avenuesguesthouse.co.za, Paardvlei, Somerset West, Cape Town, South Africa.  DustWatch cc conducted a 3 day training course from the 13^th of June to the 15^th of June 2017.

Greenmined Environmental Consultancy is a company based in Cape Town that offers environmental services including Environmental Impact Management and ECO Services, Legal Audits, Mine Impact Management (Mine Administration/Permit and Rights Applications / Environmental Closure Plan), Water Management- Authorisation Applications & Compliance, Water & Dust Monitoring and GIS Support.

Three (3) training courses have been conducted this year – two in Pretoria and one in Cape Town . A total of 4 personnel attended the training: Muechellin, Jemma, Vuyo and Sibusiswe.
Sibusiswe and Vuyo attended the training at no cost as they are students taken in as part of a mentoring program.

 Figure 1: Trainees who attended the fallout dust monitoring course

Figure 2: Table of trainees

Figure 3: Mr. Chris Loans (Director of DustWatch cc) excited to deliver the content, with Vuyo filtering dust.

Summary of the training from the 13^th June – 15^th of June is as follows:

The training kick-started on Tuesday 13^th of June 2017 with theoretical presentation by Mr. Christopher Loans (Managing Director of DustWatch cc). The theory was about fallout dust and how to collect it, Settling Velocity and shape of dust particles, Calculating fallout dust monitoring results, trace elements analysis, as well as South African Legislation interpretation.

Wednesday the 14^th of June 2017 was a practical day where trainees practiced changing DustWatch Buckets units, Basic Operational Use of the DustWatch Units, Filtering water from the buckets and collecting dust on filters for further analysis.

Figure 3: DustWatch Single Bucket Unit used for dust fallout collection.

The last day, Thursday the 15^th of June was about learning to write Fallout Dust Reports and laboratorial procedures for data capture. An assessment test was written and all trainees passed with excellent results.

 Gallery of the training

Mentored students excited in the training

Greenmined Environmental contact details

Trainees writing the assessment test

www.dustwatch.com

DustWatch CC – Precipitant Dust Monitoring
082 875 0209 or 021 789 0847 (Chris)
083 308 4764 (Gerry)
0866 181 421 (Fax)

Please do not hesitate to contact me regarding any queries.

Sincerely
Chris Loans

This is an excellent question and the answer to it will vary depending on what type of dust you have breathed in.  The truth be told, we all breathe in lots of dust everyday.  Most dust will be filtered out by the hairs and mucus lining in your nose.

However, dust that is inhaled from asbestos or fiberglass is another matter entirely.  In this case, a trip to the hospital is imperative and without delay.  Unfortunately, there is no cure for asbestos being inhaled but doctors may prescribe breathing treatments and medication to help with the symptoms.  This is why companies exist where employees have the equipment and training to remove these materials safely.

Working with wood and drywall can be dangerous because of the dust these material can create.  Always wear a dust mask to prevent dust inhalation.  Extended periods of breathing in the dust will potentially cause lung problems.

That being said if you breathe in too much dust from cleaning a dirty room you may begin to sneeze and/or cough which is your body’s attempt to remove the dust.  If you went beyond what the body can expel by sneezing and/or coughing you usually will experience a sore throat.  When this happens drinking a cool glass of water will help to flush your throat.  Sometimes a cough drop will help the throat to recover faster.

If breathing in a lot of dust around your home is a concern for you why not hire a professional cleaning company to clean your home and let them handle the dust.

For more answers go to – https://www.quora.com/What-should-I-do-after-breathing-in-a-lot-of-dust