Transcript Hearing Conservation

Safety
st
1
Course Objectives
Occupational Noise Exposure
What is it?
Monitoring Requirements
Noise Levels
Dosimeter Types
Ear Anatomy
Noise Makers
Potential High Hazard Areas
Course Objectives
Audiometric Testing
Types of Audiograms
Audio Evaluations
Hearing Protectors
Requirements & Types
Training
Recordkeeping
Occupational Noise
Exposure
Noise, or unwanted sound, is one of the
most pervasive occupational health
problems.
By-product of many industrial processes.
Sound consists of pressure changes in a
medium (usually air) caused by vibration or
turbulence.
Pressure changes produce waves
emanating away from the turbulent or
vibrating source.
Occupational Noise
Exposure
High level exposure causes hearing
loss and may cause other harmful
health effects.
Extent of damage depends on
intensity of noise and duration of
exposure.
Hearing loss can be temporary or
permanent.
Monitoring
Required program to monitor
employees if exposure is at or above
85 decibels (dB) averaged over 8
working hours or an 8-hour time
weighted average (TWA).
Repeat monitoring is required when
changes in production, process or
controls increase the noise exposure.
Monitoring
Employees are entitled to observe
monitoring procedures.
Employees must be notified of the
results of monitoring.
Monitoring methods are left to the
discretion of the employer.
Monitoring
Instruments must be carefully
checked or calibrated.
Employers have the duty to ensure
measuring instruments are properly
calibrated.
Dosimeter Types
Noise Dosimeter
Analog Sound
Level
Dosimeter Types
Digital Sound
Digital Sound
Level Meter
Level Meter
Dosimeter types
Integrating Sound
Sound Level
Level Meter
DataLogger
Ear Anatomy
Potential High Hazard Areas
Print Shops
Boiler Rooms
Motor Pools
Laundry Areas
Kitchen areas
Exposure To High Speed Hand Tools
Aircraft’s
Maintenance Shops
Audiometric Testing
The employer shall establish and
maintain an Audiometric testing
program.
Elements include:
Baseline audiograms
Annual audiograms
Training
Follow-up procedures
Audiometric Testing
Testing is at no cost to all employees who
are exposed to an action level of 85 dB or
above, measured as an 8-hour TWA.
Follow-up testing should indicate whether
the employer’s hearing conservation
program is preventing hearing loss.
A licensed or certified audiologist, an
otolaryngologist or a physician must be
responsible for the program.
Audiometric Testing
Professionals and trained technicians
may conduct audiometric testing.
The professional in charge does not
have to be present when technicians
conduct the test.
Employee referrals
Test results are questionable.
Problems of a medical nature are
suspected.
Types of Audiograms
Baseline
Reference audiogram against which
future audiograms are compared.
Provided within six months of employees
first exposure.
» There are exceptions to the six month
time frame...
Types of Audiograms
Annual Testing
Within one year of the baseline and annual
to identify possible deterioration of hearing
ability.
To initiate protective follow-up measures if
hearing loss is progressing.
To determine if a Standard Threshold Shift
(STS) has occurred .
Tests must be conducted in rooms meeting
ANSI specifications of SC-1969
Audiogram Evaluation
If an STS is identified, employees must be
fitted or refitted with adequate hearing
protectors.
Employees must be notified within 21 days
from the time the determination is made.
Some employees may need to be referred
for further testing.
If they have an ear problem of a medical
nature.
If problem is thought to be caused or
aggravated by wearing hearing protectors
Audiogram Evaluation
If STS identified on previous
audiogram is not persistent,
employees whose exposure to noise
is < a TWA of 90dB may discontinue
wearing hearing protectors.
An annual audiogram may be
substituted for the original baseline
audiogram, if...
Hearing Protectors
Must be available to employees
exposed to 8-hour TWA or 85dB or
above.
Hearing protectors must be worn by:
Employees exceeding 6 months from
the first time they are exposed.
Employees who have incurred standard
threshold shifts, and
A PEL of 90 dB over an 8-hour TWA.
Hearing Protectors
Employees should decide which size
and type protector is most suitable for
their working environment.
Hearing protectors must adequately
reduce the severity of the noise level for
each employee’s work environment.
Hearing Protectors
If workplace noise levels increase,
employees must be given more effective
protectors.
The protector must reduce the employee
exposure to at least 90 dB and to 85 dB
when an STS already has occurred.
Types of Hearing Protection
Most Common
Types
Ear Muff
Canal Cap
Ear Plug
Ear Muff
 Excellent attenuation at
low and high frequencies.
 Comfortable for
continuous use.
 Designed for maximum
attenuation in severe
noise environment
 Simple height adjustment
without projecting parts
 NRR around 27 dB
Canal Cap
 The SWIVEL insures
alignment to your ear
canal for maximum
comfort.
 Blocks noise at outer
ear passage.
 No plugs or foreign
objects in ear canal
 Weighs only 1-1/2 oz
 NRR18 dB - overhead,
NRR17 dB - behind
head or under chin
Ear Plug
 Very lightweight and
soft
 Very inexpensive
 Form fitting in the ear
canal
 One size fits most ear
canal sizes
 Disposable - one
time use
 NRR of 21dB
Ultra-Fit Ear Plug
 Many of the same
attributes as the
disposable, except:
Made from a
polymer material
instead of foam
Much more
expensive
Durable and long
lasting
 NRR 21dB
Training
Employees exposed to TWAs of 85 dB and
above must be trained at least annually in:
The effects of noise.
The purpose, advantages and
disadvantages of various types of hearing
protectors.
The selection, fit and care of protectors,
and,
The purpose and procedures of audiometric
testing.
Recordkeeping
Noise exposure measurements must be
kept for 2 years.
Record of audiometric test results must
be maintained for the duration of
employment.
Audiometric test records must include:
Name and job of employee.
The date.
The examiner’s name.
Recordkeeping
The date of the last acoustic or
exhaustive calibration.
Measurements of the background sound
pressure levels in audiometric test
rooms.
The employee’s most recent noise
exposure measurement.
Don’t End up Like This.