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Hi – my name is [insert name here] and I will be doing a presentation developed by the National Institute on Deafness and Other Communication Disorders, or NIDCD. The NIDCD is part of the National Institutes of Health, or NIH. Has anyone heard of the NIH?

Wait for answers.

The NIH is a federal agency that funds and conducts biomedical research. There are 27 Institutes and Centers within the NIH. Each one focuses on a different body part or disease type. At the NIDCD, one of the topics that they study is hearing loss.

Ask: “What age do you think hearing loss happens?” and call on kids for answers.

When you hear the words “hearing loss” most people think of older people and that certainly can be the case. People do tend to lose their hearing as they age. But hearing loss can affect anyone, no matter what their age is.

Ask: “Would you agree that it’s a noisy planet?”

Ask: “What are some examples of noisy activities and noisy places?”

Just like you mentioned, some examples of noisy activities include:

Concerts
Traffic
Fireworks
Listening to loud music through headphones
Movie theaters

Today we’ll talk about noise (point to “Noisy” on slide) and hearing loss (point to “Hearing” on slide), and what we can do to protect our hearing against damage caused by noise, which is called noise-induced hearing loss (point to the word “Protect” on slide).

Ask: “Can you tell me what we can do to protect our hearing from noise-induced hearing loss?”

Review three activities: lower the volume, move away from the noise, and wear hearing protectors, such as earplugs and earmuffs.

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What Is Sound?

Sound is energy, like light or electricity.
Sound is made when objects vibrate.
Sound vibrations travel in waves by pushing �air molecules together.
Vibrations can be powerful. The stronger the vibrations, �the louder the sound.
Sound is measured in decibels.

[Noisy Planet Student Activity: Refer to the Tuning Fork Demonstration video as a guide (https://www.noisyplanet.nidcd.nih.gov/educators/teacher-toolkit).]

Before we can understand how noises can affect our hearing, we need to understand sound. What is sound?

Wait for them to suggest answers. Then, one by one, click on the “enter” key to bring up each bullet.

1) Sound is energy, like light or electricity.

Use the crank flashlight to show how energy is needed to turn it on.

This demonstration shows how energy cannot be created or destroyed but transformed from one type into another—from mechanical energy (turning the crank) into electrical energy.

2) Sound is caused by pushing air molecules together.

Try clapping your hands. The force of your hands coming together causes molecules in the air to be pushed together. That compression travels through the air in all directions, and will soon reach your ears.

3) Sound is often made by vibrations in the air.

Some sounds are caused by vibrations, which are rhythmic compressions of air. We call these sound waves.

Ask: “What are some examples of things that vibrate to cause sound?” (a bell, guitar string, blowing on a blade of grass, your vocal cords/folds when you speak)

4) Vibrations can be powerful. The stronger the vibrations, the louder the sound.

Demonstrate how vibrations from a tuning fork affect a ping-pong ball. (Hold the ping-pong ball against a tuning fork. The tuning fork isn’t vibrating, so the ping-pong will be still. Then, strike the tuning fork hard on the bottom of your shoe or on the ground or table. When the tuning fork is vibrating, it makes a sound, and the ping-pong ball will bounce against it.).

Demonstrate how a plastic cup telephone works. (When you speak into the cup, it causes the bottom of the cup to vibrate. This vibration causes the fishing wire connecting the two cups to vibrate, which vibrates the bottom of the second cup, and that enables you to hear the person’s voice).

5) Sound is measured in decibels.

What other things do you measure?

Give examples of units of measure for height, weight, or temperature (inches, pounds, degrees, etc.).

The decibel range that we can hear is roughly 0 decibels to over 100 decibels. The softer the sound, the lower the sound pressure, and the lower the decibel level; the louder the sound, the higher the sound pressure, and the higher the decibel level. The softest sound is 0 decibels, which is like the sound of a pin drop. A whisper is around 30 decibels. Normal conversation is around 60 decibels. Prolonged exposure to any noise at or above 85 decibels can cause gradual hearing loss. The louder the sound, the shorter the period of exposure before hearing loss results.

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How Do We Hear?

Eardrum

Cochlea

[Noisy Planet Student Activity: Refer to the How We Hear Demonstration video as a guide. (https://www.noisyplanet.nidcd.nih.gov/educators/teacher-toolkit)]

Our ear is an amazing instrument for capturing sound vibrations. Take a trumpet, for instance. When it's played, it makes sound waves in the air. The outer ear catches the waves, which then travel through a narrow passageway called the ear canal.

The sound waves reach the eardrum. The sound waves make the eardrum vibrate, which in turn vibrates three tiny bones called the malleus, incus, and stapes. These are the smallest bones in your body and together they are smaller than an orange seed. These bones amplify, or increase, the sound vibrations and send them to the cochlea, the part of the inner ear that is shaped like a snail.

The cochlea is filled with fluid, and the vibrations make waves in the fluid. Sensory hearing cells get activated as the wave reaches the part of the cochlea that they are sitting in.

Have 7 students act out the process: Kids should line up in a straight line, side-by-side, facing the classroom. The first kid acts as the noise source (bike horn). The second kid acts as the eardrum (he/she is holding a round vinyl disk); the next three kids act as the malleus, the incus, and the stapes. The fifth kid acts as the cochlea and stands to the right of the child acting as the stapes. The last kid is the brain (flashlight). When the first kid honks the horn, the second kid bangs the “eardrum,” the next three kids representing the three bones start vibrating/wiggling/dancing, the kid acting as the cochlea starts sloshing, and the last kid turns on the flashlight to show the electrical signal has reached the brain.

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Sound can damage our hearing

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HOW LOUD IS TOO LOUD?

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How Loud Is Too Loud? �

https://www.noisyplanet.nidcd.nih.gov/kids-preteens/listen-up-infographic

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YOUR OWN NOISY CLASS CAN DAMAGE YOUR HEARING.

LOOK!

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Day	Maximum	Minimum
Friday (Biology)	80 db	40 db
Tuesday (Literacy)	110 db	60 db
Tuesday (Biology)	90 db	45 db

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What can you do�to protect your hearing?

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Show the types of hearing protectors.

Expandable foam earplugs are formable earplugs that are created to expand and mold to the shape of each user’s ear canal.

Demonstrate how to put in and remove earplugs: Roll the earplug into a thin, crease-free cylinder. The tube must be thin enough so that half of the length will fit easily into the ear canal. Slide tube halfway into ear canal and leave to expand until there is a tight seal.

Canal caps often look like ear plugs on a flexible plastic or metal band with either a moldable or premolded tip. These may be either connected by a band to place over the head or jointed bands.

Demonstrate how to put in and remove canal caps: Place the band in its respective location and slide the earplug halfway into your ear canal (form them beforehand if they are the moldable type).

Earmuffs are plastic cups that cover the outer ear that protection from outside noise. They fit most users and come with different size cups.

Demonstrate how to put on earmuffs: Grab each cup of the ear muffs, one in each hand, and pull apart to stretch. Place the band over the top of your head and slowly release the cups so their placement covers the outer ear.

High-fidelity earplugs are made from hardened silicone, plastic, or rubber, and come in either a variety of sizes, or “one-size-fits-most.” Custom high-fidelity earplugs are custom made for each user’s ear. They are made by making an impression of the ear canal, and then the molds are formed. These earplugs don't change sound quality except for making it softer, which can be useful when it’s important to hear speech.

Demonstrate how to put on high-fidelity earplugs: Reach over your head with one hand to pull up on your ear. Then use your other hand to insert the plug with a gentle rocking motion until you have sealed the ear canal. Custom ear plugs should fit easier without having to do the rocking motion for insertion.

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For more information, visit:

https://www.noisyplanet.nidcd.nih.gov

Presentation adapted from Dangerous Decibels, partner to the Noisy Planet campaign