HEARING CONSERVATION

HEARING CONSERVATION

Hearing LossHearing Loss Can you imagine not being

able to:– Hear music?– Listen to the sounds of

nature?– Socialize with your family?

Can you imagine being afflicted with uncomfortable ringing or abnormal sounds that interfere with sleep?

The Impact Of Noise The Impact Of Noise

Interferes with communication

Causes fatigue Distracting or irritating Reduces morale

or efficiency

Anatomy Of The EarAnatomy Of The Ear

The Outer EarThe Outer Ear

The Middle EarThe Middle Ear

The Inner EarThe Inner Ear

Several animals can hear sounds of much higher frequency, which is why humans do not hear special whistles that may be heard by dogs.

Sounds vary not only in frequency, but also in intensity.

SoundsSounds

The measure of sound pressure

The decibel is a relative measure

5 dBA exchange rate

DecibelDecibel

16

86

4 3 2 1.5 1 .5 .25

85 90 92 95 97 100 102 105 110 115

Permissible Noise Exposure

Permissible Noise Exposure

3030

WhisperWhisper90 dB90 dB

6060

TalkingTalking90 dB90 dB

8080

TrafficTraffic90 dB90 dB

8585

HaulTruckHaul

Truck 90 dB90 dB

8686

LoaderLoader90 dB90 dB

9191

LawnMowerLawn

Mower 90 dB90 dB

103103

ImpactWrenchImpactWrench 90 dB90 dB

105105

DozerDozer90 dB90 dB

109109

ScreensScreens90 dB90 dB

110110

ChainSaw

ChainSaw 90 dB90 dB

120120

RockConcert

RockConcert 90 dB90 dB

125125

MetalBanging

MetalBanging 90 dB90 dB

140140

JetAirplane

JetAirplane 90 dB90 dB

Threshold of pain

165165

12-GaugeShotgun12-GaugeShotgun 90 dB90 dB

NIOSH estimates that 30 million workers are exposed to hazardous noise levels

At present exposure limits, one in four workers will develop permanent hearing loss

Hearing ExposureHearing Exposure

Two Categories of hearing

Loss:

Hearing ExposureHearing Exposure

Temporary Permanent

Wax build up Measles / Otosclerosis Aging Head injury Drugs / Medicine Chemicals Heredity

Hearing Loss CausesHearing Loss Causes

Fail to catch words

Ears ringing Shouting

without realizing

Trouble understanding high frequency sounds in speech

Signs of Hearing LossSigns of Hearing Loss

Demonstration of Hearing Loss

Demonstration of Hearing Loss

Sound tracks of a male voice, with no background noise

– Normal– Loss of 25 dB– Loss of 40 dB– Loss of 60 dB– Normal

Action Level 85 dB - Must inform employees & enroll them in a hearing conservation program

Permissible Exposure Level 90 dB - Must enroll employee in a hearing conservation program, use all controls to reduce exposure, must wear hearing protection

Dual Protection Level 105 dB - Must wear both plugs and earmuffs

Noise StandardNoise Standard

Engineering Controls– Eliminate or reduce the noise

at the source– Interrupting the noise path– Reducing reverberation

Administrative Controls– Change in work schedule– Quiet areas for breaks– Job rotation

Eliminating NoiseEliminating Noise

Monitoring system Hearing protection Audiometric testing Training Recordkeeping

Hearing Conservation Program

Hearing Conservation Program

AudiogramsAudiograms

Audiometric testing offered

Qualified medical provider

Baseline tests Annual testing

Standard Threshold ShiftStandard Threshold Shift Hearing changed

by 10 db average Employee

notification within 21 days

Revised hearing protection required

Further medical evaluation

Dosimeter

Sound Level Meter

MonitoringMonitoring

Listed on the package How many decibels are blocked OSHA subtracts the NRR by 50% NIOSH subtracts the NRR by 25%

for earmuffs, 50% for formable plugs, and 70% for all other plugs

Noise Reduction Rating (NRR)

Noise Reduction Rating (NRR)

Reusable and Headband Plugs– 25 to 35 dB NRR

– Preformed to fit ear

– Flexible rubber

– Inspect and clean

– Replace when hard or damaged

Hearing ProtectionHearing Protection

Disposable Plugs– 25 to 35 dB NRR– Expandable foam– One size fits all– Insert with clean

hands– If damaged or dirty

throw them away

Hearing ProtectionHearing Protection

Inserting PlugsInserting Plugs

Earmuffs– 22 to 29 dB NRR– Foam filled cushions– Hard to get good

seal– Works well with

plugs– Replace when stiff or

worn

Hearing ProtectionHearing Protection

Advantages Disadvantages

Ear Plugs Good NRR. Hard to wear.Get dirty.

Ear Muffs Easy to wear.Fits everyone.

Fair NRR.Expensive.Easily broken.

Plugs vs. EarmuffsPlugs vs. Earmuffs

Prolonged noise exposure causes permanent hearing loss

Hearing loss is preventable, so wear your hearing protection!

ConclusionConclusion

Wear this now...

Or wear this later!

It’s Really Pretty Simple…..

It’s Really Pretty Simple…..