NOISENOISE

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Noise - what is it?Noise - what is it?

• Unwanted soundUnwanted sound• sound is vibrations in airsound is vibrations in air

• Sound Pressure LevelSound Pressure Level• decibels (dB) - sound decibels (dB) - sound

loudnessloudness

• FrequencyFrequency• hertz (Hz) - vibrations hertz (Hz) - vibrations

per secondper second

• Good human ears hear Good human ears hear sounds between sounds between 20 to 20,000 Hz.20 to 20,000 Hz.

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Types of Noise Types of Noise

• ContinuousContinuous• same noise level over long periodssame noise level over long periods

• IntermittentIntermittent• periods of quiet interrupted by noise periods of quiet interrupted by noise • most noise exposures are intermittentmost noise exposures are intermittent

• Impact or impulsiveImpact or impulsive• nail gunnail gun

• Most jobs have combinations of all noise Most jobs have combinations of all noise typestypes

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Is noise a big problem?Is noise a big problem?• 28 Million Americans affected28 Million Americans affected

• NIOSH says 2.5 million workers/year are affectedNIOSH says 2.5 million workers/year are affected• Over 500,000 construction workers are Over 500,000 construction workers are

overexposed.overexposed.• 50% of construction workers may have 50% of construction workers may have

some job-related hearing losssome job-related hearing loss• 33% of hearing loss is from NIHL33% of hearing loss is from NIHL• A 25 year old construction worker has the A 25 year old construction worker has the

hearing of a 50 year old without noise hearing of a 50 year old without noise exposureexposure

• Once hearing is gone, it is lost foreverOnce hearing is gone, it is lost forever

Source: Construction Safety Association of OntarioSource: Construction Safety Association of Ontario

Construction WorkersConstruction Workers

What does that What does that mean to our workersmean to our workers

How do we protect How do we protect themthem

Hierarchy of controlsHierarchy of controls Common exposuresCommon exposures

– jackhammerjackhammer– power toolspower tools– heavy machineryheavy machinery

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YouYou

What does that mean to you?What does that mean to you? Loss of hearing through aging Loss of hearing through aging

(presbycusis)(presbycusis) Born with ~ 40,000 cilia Born with ~ 40,000 cilia

in ear canalin ear canal Common ExposuresCommon Exposures

– iPods, headphonesiPods, headphones– loud music/concertsloud music/concerts– huntinghunting– otherother

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DecibelsDecibels

Noise levels are measured in decibels (dBA)Noise levels are measured in decibels (dBA)

• A small increase in decibels equates to a large A small increase in decibels equates to a large increase in noise (logarithmic)increase in noise (logarithmic)

• An increase of just 3 dB doubles the amount of An increase of just 3 dB doubles the amount of sound 88 dB can do twice as much harm to your sound 88 dB can do twice as much harm to your ears as 85 dB. An increase of 10 dB means it is ears as 85 dB. An increase of 10 dB means it is 10 times louder10 times louder

• Typical levels:Typical levels:• 65- normal conversation65- normal conversation• 75- busy street corner75- busy street corner• 85- background noise on a construction site85- background noise on a construction site

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How Do We Hear?How Do We Hear?

• Outer ear collects Outer ear collects sound and vibrates sound and vibrates eardrumeardrum

• Eardrum vibrates Eardrum vibrates bones in middle earbones in middle ear

• Bones transmit Bones transmit vibrations to cochlea vibrations to cochlea (inner ear)(inner ear)

• Cochlea hair cells are Cochlea hair cells are connected to auditory connected to auditory nerve that runs to the nerve that runs to the brainbrain

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Effects of NoiseEffects of Noise

• Temporary Threshold Shift (TTS) Temporary Threshold Shift (TTS) • temporary hearing losstemporary hearing loss• early sign of a hearing problemearly sign of a hearing problem• recovery within hours after exposurerecovery within hours after exposure

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Effects of Noise Effects of Noise

• Permanent Threshold Shift Permanent Threshold Shift • permanent hearing losspermanent hearing loss• destroys hair cellsdestroys hair cells• no treatment or cureno treatment or cure• gradualgradual

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Effects of NoiseEffects of Noise

• Tinnitus - Tinnitus - ringing in the earsringing in the ears• Non-auditory problemsNon-auditory problems

• Constant state of “alert”Constant state of “alert”• Disturbed sleeping patternsDisturbed sleeping patterns• Increased blood pressureIncreased blood pressure

• PresbycusisPresbycusis• hearing loss from aginghearing loss from aging• may be compounded by excess noisemay be compounded by excess noise

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Effects of Hearing LossEffects of Hearing Loss

• Hearing loss makes it harder to Hearing loss makes it harder to communicate on the job, with communicate on the job, with friends and family, especially in friends and family, especially in noisy places like jobsites and noisy places like jobsites and restaurantsrestaurants

• Hearing loss can make it difficult Hearing loss can make it difficult to hear warning signs like back up to hear warning signs like back up alarms or traffic on a streetalarms or traffic on a street

Other Health EffectsOther Health Effects

Make you feel tired/fatiguedMake you feel tired/fatigued Heighten nervousnessHeighten nervousness Raise in blood pressureRaise in blood pressure Increase risks of heart problemsIncrease risks of heart problems May also effect sense of balanceMay also effect sense of balance These effects are permanentThese effects are permanent

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What can you do?What can you do? Turn down the volumeTurn down the volume

– When listening to music on earphones at When listening to music on earphones at a medium volume, the noise generated a medium volume, the noise generated reaches up to 100dBAreaches up to 100dBA

– Loud enough to cause permanent Loud enough to cause permanent damage after damage after just 15 minutes/dayjust 15 minutes/day

Use hearing protectionUse hearing protection Walk awayWalk away 3 Foot Rule3 Foot Rule

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OSHA RequirementsOSHA Requirements

Construction 90 dBaConstruction 90 dBa

General Industry 85 dBGeneral Industry 85 dB

Hearing Conservation Program Hearing Conservation Program (1926.52)(1926.52)

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OSHA Table D-2 OSHA Table D-2 Permissible Noise Permissible Noise

ExposuresExposuresDuration per day,

hoursSound Level

dBA (slow response)

8 90

6 92

4 95

3 97

2 100

1.5 102

1 105

.5 110

.25 or less 1151717

Task-Based MethodTask-Based Method

ANSI A10.46-ANSI A10.46-Hearing Loss Prevention in Construction and Demolition Workers

When equipment or tasks expose When equipment or tasks expose workers to sound levels exceeding 85 workers to sound levels exceeding 85 dBA, engineering or administrative dBA, engineering or administrative controls should be implementedcontrols should be implemented

Where controls are infeasible or fail to Where controls are infeasible or fail to reduce sound levels below 85 dBA, reduce sound levels below 85 dBA, HPD’s shall be provided and used by HPD’s shall be provided and used by employeesemployees

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Effective Hearing Effective Hearing Conservation ProgramConservation Program

1.1. Monitoring of employees’ noise exposures,Monitoring of employees’ noise exposures,

2.2. Engineering, work practice, and Engineering, work practice, and administrative controls,administrative controls,

3.3. PPEPPE

4.4. Employee training and educationEmployee training and education

5.5. Baseline and annual audiometry, Baseline and annual audiometry,

6.6. Procedures for preventing further Procedures for preventing further occupational hearing loss occupational hearing loss

7.7. Recording Keeping Recording Keeping

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2020

Hearing ProtectorsHearing Protectors

• Ear PlugsEar Plugs

• Semi-InsertsSemi-Inserts

• Ear MuffsEar Muffs

• AttenuationAttenuation

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Ear PlugsEar Plugs

• FormableFormable• Pre-moldedPre-molded• Custom-moldedCustom-molded• ProsPros

• cooler in hot weather, cooler in hot weather, cheapercheaper

• ConsCons• attenuation varies with fitattenuation varies with fit• easier to loseeasier to lose• hygiene problems hygiene problems

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Ear PlugsEar Plugs

• To fit correctly, ear To fit correctly, ear plugs must be inserted plugs must be inserted snugly into the ear snugly into the ear canal.canal.

• Make sure the foam Make sure the foam plugs are rolled up tight plugs are rolled up tight and is crease free. Use and is crease free. Use the Roll model for the Roll model for practicing.practicing.

• Pull back gently on the Pull back gently on the ear with your opposite ear with your opposite had to straighten out had to straighten out the canal while the canal while inserting the plug.inserting the plug.

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Proper FitProper Fit

• Ear plug is snug Ear plug is snug in the ear canalin the ear canal

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Incorrect FitIncorrect Fit

• Ear plug is not in Ear plug is not in snug and snug and protection level is protection level is much lowermuch lower

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Semi-Inserts Semi-Inserts

• Ear plug connected by Ear plug connected by headbandheadband

• Insert into the canal Insert into the canal or cap over itor cap over it

• Intended to be worn Intended to be worn for short durationfor short duration

• ProsPros• easier to take on and easier to take on and

offoff• ConsCons

• uncomfortable for uncomfortable for extended useextended use

• smaller attenuationsmaller attenuation

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Ear MuffsEar Muffs

• Plastic cups attached by Plastic cups attached by headbandheadband

• ProsPros• easier to fit to most easier to fit to most

people, more consistent people, more consistent attenuation than plugs, attenuation than plugs, can be fitted hardhatscan be fitted hardhats

• ConsCons• heavier/hotter than heavier/hotter than

plugs, plugs, • headband pressure can headband pressure can

make long wear make long wear uncomfortableuncomfortable