howard leight-bilsom basics of hearing conservation

7/30/2019 Howard Leight-Bilsom Basics of Hearing Conservation

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and off the job.

NOISE AND ACOUSTICS

Hazardous noise exposures occur

on the job ..


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NOISE AND ACOUSTICS

Noise-Induced Hearing Loss Causes no pain

Causes no visible trauma

Leaves no visible scars

Is unnoticeable in its earliest stages

Accumulates with each over-exposure

Takes years to diagnose

Is permanent and 100% preventable


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NOISE AND ACOUSTICS


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NOISE AND ACOUSTICS

How do I know if the noise levels are hazardous?

If you must shout to be understood over

the background noise when standingabout one arm-length away from

somebody,

that background noise is

hazardous.


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NOISE AND ACOUSTICS

Time-Weighted Average

Permissible Exposure Limits


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OSHA STANDARD

Time-Weighted Average

Permissible Exposure Limits


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HOW WE HEAR

Sound waves causethe eardrum to vibrate

Bones in middle eartransmit vibrations tocochlea

Receptors (hair cells)in cochlea convertvibrations to electricalenergy

Brain interprets theseelectrical impulses assound


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HOW WE HEAR

Nerve cells in thecochlea are tuned tospecific frequencies

Base of the cochlea is

sensitive to highfrequency sounds

Tip of the cochlea issensitive to low

frequency sounds


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HOW WE HEAR

17-year old girl

Low noise exposure

Normal cochlea

Receptors intact

76-year old man

Low noise exposure

Fewer receptors butstill intact

59-year old man

High noise exposure

Damaged cochlea

Receptors destroyed


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HOW WE HEAR

High-frequency sounds of speech

TF

High-frequency


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HPD SELECTION

The BestHearingProtection

COMPATIBILITYWITH OTHER

PPE

COMPATIBILITYWITH OTHER

PPE

COMFORTCOMFORT

NOISEREDUCTION

NOISEREDUCTION

SIZESIZE

COMMUNICATIONNEEDS

COMMUNICATIONNEEDS

SPECIAL JOBREQUIREMENTS

SPECIAL JOBREQUIREMENTS

CLEANLINESSCLEANLINESS


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HPD SELECTION

Common Objections to Wearing HPDs

Hearing protectors are

uncomfortable.

I dont need them, I

am used to the

noise.

I already lost some of my

hearing, so why should I

wear them?

I cant hear my

co-workers if I

wear them.

I can alwaysget a hearing aid.

Can I hurt my

eardrums if I insert a

plug to deeply.

My machine

sounds different.

Wont I get anear infection?


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FITTING TIPS

Find the Right Size

Maximum protection is onlyaccomplished when an earplugacoustically seals in the ear canal.

No earplug fits all ear canals, somanufacturers have respondedwith a variety of sizes.

It is important to find your right sizeto obtain an acoustic seal


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FITTING TIPS

ROLL-DOWN FOAM

2. Pull Backpinna by reaching overhead with free hand,gently pull top of ear up

and out

1. Rollentire earplug into acrease-free cylinder

3. Insertearplug well

into earcanal andhold until itfully expands


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FITTING TIPS

Visual Check for Foam Earplugs

If properly fitted, the end of the earplugs should notextend beyond the tragus (flap of the ear canal).


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1. Reachover head withfree hand, pull earup and back andinsert earplug wellinside ear canal.

2. Earplugsshould be insertedas shown in thesedrawings. Stoppushing earplugwhen finger

touches the ear.

3. If properlyfitted, the end ofthe earplugsshould not bevisible to someonelooking at you

from the front.

NO-ROLL FOAM EARPLUGS


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MULTIPLE-USE EARPLUGS

1. While holding thestem, reach handoverhead and gentlypull top of ear upand back.

2. Insert earplugso all flangesare well insidethe ear canal.

3. If properlyfitted, only thestem of theearplugs

should bevisible tosomeonelooking at youfrom the front.


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2. Acoustical Check -Cup hands over ears

and release. Earplugs

should block enough

noise so that covering

your ears with hands

should not result in a

significant noise

difference.

EARPLUGS (ALL)

1. Visual Check - Theearplug should sit wellinside the ear canal andnot stick out.


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1. Place earcupsover eachouter ear

2. Adjust theheadband bysliding theheadband up ordown at theattachment

buttons

3. The earcushions shouldseal firmlyagainst the head

EARMUFF INSTRUCTIONS


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EARMUFF INSTRUCTIONSDONTS

For best results, removeall hair from underneathearcup.

Ensure that the earcupcreates a seal and coversthe ear completely.


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PRODUCTS

Types of Hearing Protectors

Earplugs

Single-Use

Multiple-Use

Detectable

Banded Protectors Banded Earplugs

Canal Caps

Earmuffs

Standard (Headband)

Cap-Mounted Electronic

Special Application


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PROS AND CONS OF HPDs EARPLUGS

PROComfortable for extended use

Disposable earplugs available

Cooler in hot/humid

environments

CONAttenuation highly dependent

upon good fit

Hygiene issues in dirty

environments


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CARE & MAINTENANCE OF HPDs EARPLUGS

Dispose of single-use

earplugs daily

Clean multiple-use

earplugs with mild soapand water, dry thoroughly

Inspect multiple-use

earplugs for dirt, cracks or

hardness, replace ifdamaged


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PROS AND CONS OF HPDs BANDED EARPLUGS

Clean and replace pods

regularly


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CARE & MAINTENANCE OF HPDs BANDED EARPLUGS

PROVery convenient for intermittent

noise

Readily available around neck

when not in use

CONLower attenuation than most

earplugs

Some noise transmission

through band


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PROS AND CONS OF HPDs EARMUFFS

PROEasy to get proper fit

Good for intermittent noise

Radio & electronic options

CONCan feel hot/heavy with

extended wear

Compatibility with other PPE?


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CARE & MAINTENANCE OF HPDs EARMUFFS

Clean ear cushions and

headband regularly with

mild soap and water

Replace ear cushionsandfoam inserts every 6

months with normal wear,

more often with heavy use

or under humid/extremeconditions


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Hearing Loss Due To

Noise Exposure Is

Painless

PermanentProgressive

and very PREVENTABLE!


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howard leight-bilsom basics of hearing conservation

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