NOISE

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Noise - what is it?

• Unwanted sound • sound is vibrations in air • Sound Pressure Level • decibels (dB) - sound loudness • Frequency • hertz (Hz) - vibrations per second • Good human ears hear sounds between 20 to 20,000 Hz.

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Types of Noise

• • • • Continuous • same noise level over long periods Intermittent • periods of quiet interrupted by noise • most noise exposures are intermittent Impact or impulsive • nail gun Most jobs have combinations of all noise types 3

Is noise a big problem?

• • • • • 28 Million Americans affected • NIOSH says 2.5 million workers/year are affected • Over 500,000 construction workers are overexposed.

50% of construction workers may have some job-related hearing loss 33% of hearing loss is from NIHL A 25 year old construction worker has the hearing of a 50 year old without noise exposure Once hearing is gone, it is lost forever 4

Source: Construction Safety Association of Ontario

Construction Workers

    What does that mean to our workers How do we protect them Hierarchy of controls Common exposures – jackhammer – power tools – heavy machinery 6

You

    What does that mean to you?

Loss of hearing through aging (presbycusis) Born with ~ 40,000 cilia in ear canal Common Exposures – iPods, headphones – loud music/concerts – hunting – other 7

Decibels

Noise levels are measured in decibels (dBA) • A small increase in decibels equates to a large increase in noise (logarithmic) • An increase of just 3 dB doubles the amount of sound 88 dB can do twice as much harm to your ears as 85 dB. An increase of 10 dB means it is 10 times louder • Typical levels: • • • 65- normal conversation 75- busy street corner 85- background noise on a construction site 8

How Do We Hear?

• • • • Outer ear collects sound and vibrates eardrum Eardrum vibrates bones in middle ear Bones transmit vibrations to cochlea (inner ear) Cochlea hair cells are connected to auditory nerve that runs to the brain 9

Effects of Noise

• Temporary Threshold Shift (TTS) • temporary hearing loss • early sign of a hearing problem • recovery within hours after exposure 10

Effects of Noise

• Permanent Threshold Shift • permanent hearing loss • destroys hair cells • no treatment or cure • gradual 11

Effects of Noise

• • • Tinnitus ringing in the ears Non-auditory problems • Constant state of “alert” • Disturbed sleeping patterns • Increased blood pressure Presbycusis • hearing loss from aging • may be compounded by excess noise 12

Effects of Hearing Loss

• • Hearing loss makes it harder to communicate on the job, with friends and family, especially in noisy places like jobsites and restaurants Hearing loss can make it difficult to hear warning signs like back up alarms or traffic on a street 13

Other Health Effects

      Make you feel tired/fatigued Heighten nervousness Raise in blood pressure Increase risks of heart problems May also effect sense of balance These effects are permanent 14

What can you do?

    Turn down the volume – When listening to music on earphones at a medium volume, the noise generated reaches up to 100dBA – Loud enough to cause permanent damage after just 15 minutes/day Use hearing protection Walk away 3 Foot Rule 15

OSHA Requirements

 Construction 90 dBa  General Industry 85 dB  Hearing Conservation Program (1926.52) 16

OSHA Table D-2 Permissible Noise Exposures

Duration per day, hours Sound Level dBA (slow response)

8 90 6 4 92 95 3 2 1.5

1 .5

.25 or less 97 100 102 105 110 115 17

Task-Based Method

   ANSI A10.46-

Hearing Loss Prevention in Construction and Demolition Workers

When equipment or tasks expose workers to sound levels exceeding 85 dBA, engineering or administrative controls should be implemented Where controls are infeasible or fail to reduce sound levels below 85 dBA, HPD’s shall be provided and used by employees 18

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Effective Hearing Conservation Program

Monitoring of employees’ noise exposures, Engineering, work practice, and administrative controls, PPE Employee training and education Baseline and annual audiometry, Procedures for preventing further occupational hearing loss Recording Keeping 19

Hearing Protectors

• Ear Plugs • Semi-Inserts • Ear Muffs • Attenuation 20

Ear Plugs

• • • • • Formable Pre-molded Custom-molded Pros • cooler in hot weather, cheaper Cons • attenuation varies with fit • easier to lose • hygiene problems 21

Ear Plugs

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

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

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

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Proper Fit

• Ear plug is snug in the ear canal 23

Incorrect Fit

• Ear plug is not in snug and protection level is much lower 24

Semi-Inserts

• • • • • Ear plug connected by headband Insert into the canal or cap over it Intended to be worn for short duration Pros • easier to take on and off Cons • uncomfortable for extended use • smaller attenuation 25

Ear Muffs

• • • Plastic cups attached by headband Pros • easier to fit to most people, more consistent attenuation than plugs, can be fitted hardhats Cons • heavier/hotter than plugs, • headband pressure can make long wear uncomfortable 26