Industrial Hygiene - Noise (Presentation)
-
Upload
mohan-prasad -
Category
Documents
-
view
26 -
download
0
description
Transcript of Industrial Hygiene - Noise (Presentation)
-
INDUSTRIAL HYGIENE ~ NOISEPrevention Workshop Series
-
Housekeeping Items
Cell phones
Washrooms / Breaks
Fire exits
Evaluation
-
Introductions
Name
Company
Position / Role in OH&S
Ice BreakerIce Breaker
-
The Workplace Health, Safety and The Workplace Health, Safety and
Compensation CommissionCompensation Commission
-
Getting to Know Us!
Our Vision
The vision of the Commission is of safe and healthy
workplaces within a viable and sustainable system which
reduces the impact of workplace injuries by providing the
highest level of service to workers and employers
-
Getting to Know Us!
Our Mission
By December 31, 2010, the Commission will have improved
client service to support the prevention and management of
workplace injuries, illnesses and known occupational
disease
-
Prevention Services
Field Services
Health and Safety Advisors
Ergonomist
Consulting
Mentoring
OH&S program development and implementation supportOH&S program development and implementation support
Auditing
*Liaise with Department of Government Services (OH&S Division)
-
Prevention Services
Prevention Programs
Injury trend analysis
Training Standards & Certification
OH&S Committee / WH&S Representative / Designate
Young workersYoung workers
Small business
Resource development
-
Workshop Agenda
Sound & Hearing
Health Effects of Noise Exposure
Impact of Occupational Hearing Loss
Overview of Legislation and CSA Standards
Noise Exposure Limits
Controlling Occupational Noise ExposureControlling Occupational Noise Exposure
Hearing Conservation Program
Hearing Protection Devices
-
Sound and Hearing
Noise is a result of pressure
changes in the air created by
vibrations
Transferred to the ear by sound
waves
The human ear is a pressure-The human ear is a pressure-
sensitive device
Sound waves are converted to
sound by delicate hair cells called
cilia found in the inner ear
-
Why is Noise an Important Occupational Hazard?
One of the most common occupational health hazards
(occurs in many industries and work environments)
Permanent hearing loss is the main health concern in:
Heavy industrial and manufacturing environments
FarmsFarms
Cafeterias
-
Why is Noise an Important Occupational Hazard?
Annoyance, stress and interference with speech
communication occurs in:
Noisy offices
Schools
Computer roomsComputer rooms
-
Noise in Occupational Settings
Continuous noise
Noise level remains constant and steady over a given time period
Variable/intermittent noise
Noise levels vary with time or there are periods of relative quiet mixed
with the noise
Impulse/impact noiseImpulse/impact noise
A very short burst of loud noise followed by period of quiet
(gun shots, hammering, a punch press)
-
How Noise Can Damage Hearing
Exposure to loud noise over time
Damage is irreversible
Result is permanent hearing loss
Noise induced hearing loss occurs gradually (years), and is rarely
painful
Temporary and permanent hearing loss associated with
damage/destruction of the hair cells in the inner eardamage/destruction of the hair cells in the inner ear
Impact/impulse noise exposure
Acoustic trauma sudden hearing damage caused by short burst of
extremely loud noise such as a gun shot
-
How Many Claims
Result From Hearing Loss?
200
250
300
350
400
450Total Claims374
426
339
305
218
146
0
50
100
150
200
2003 2004 2005 2006 2007 2008 2009
Accident Year
146
104
-
The Cost of Hearing Loss Related Claims
WHSCC, 2003-2009
$2,000,000.00
$2,500,000.00
$3,000,000.00
$3,500,000.00
Total Claims Cost
Scale
$0.00
$500,000.00
$1,000,000.00
$1,500,000.00
2003 2004 2005 2006 2007 2008 2009
Accident Year
Scale
2m 18m
-
Short Term Health Effects of Noise Exposure
Auditory fatigue
Condition that results from exposure to high sound levels
Temporary loss of hearing sensitivity (Temporary Threshold Shift)
May be experienced daily after a work shift (after one shift)
Sounds appear muffled
Gradual recovery of hearing when affected person spends time in a Gradual recovery of hearing when affected person spends time in a
quiet place
Complete recovery may take several hours
Precursor of permanent hearing loss (Permanent Threshold Shift )
-
Short Term Health Effects of Noise Exposure
Tinnitus (Ringing or buzzing in the ear)
Stress, annoyance, difficulty in verbal communication
-
Long Term Health Effects of Noise Exposure
The primary health effect is permanent hearing loss
Persistent annoying Tinnitus (Ringing or buzzing in the ear)
Common among individuals with occupational hearing loss
May impair concentration
Interfere with rest and sleep
* Both short term and long term effects can be prevented * Both short term and long term effects can be prevented
-
Other Considerations in Hearing Loss
Age related hearing loss (Presbycusis)
Hearing sensitivity declines as people age
Age-related hearing loss adds to noise-induced hearing loss
Exposure to vibration and workplace noise
Combined effect
Exposure to chemicalsExposure to chemicals
Some chemicals are toxic to the hearing organs or nerves to these
organs (e.g. toluene, carbon disulfide)
Workers exposed to noise and ototoxic chemicals may suffer from
more hearing impairment
-
Incidence of Hearing LossCause and Gender
Age related hearing loss
Incidence in females a little
less than males
Occupational noise induced
hearing losshearing loss
Males disproportionately
affected
-
Effects of Noise in the Workplace
Impaired hearing
(masking of auditory signals, auditory fatigue, permanent hearing loss)
Impaired communication
Annoyance
Impaired performance
Stress
(headaches, increased heart rate, blood pressure, increased risk of
cardiovascular disease, etc.)
These factors heighten the Risk of Accident
-
Impact of Occupational Hearing Loss
(OHL) on Workers Lives
Work:
Increased risk of accidents because of inability to detect
auditory warning sounds in the workplace
Workers with OHL are more subject to accidents than normal hearing
workers, even more so if hearing protection is worn
Increased risk of accidents because of impaired speech
perception
-
Impact of Occupational Hearing Loss
(OHL) on Workers Lives
Social Activities:
Restrictions in social activities (telephone conversations, group conversations, listening in social gatherings and large halls, banks,
stores, etc.)
Increased effort and stress in listening and communication Increased effort and stress in listening and communication
situations outside the workplace
Reduced autonomy, increased isolation, diminished quality of
life
-
Impact of Occupational Hearing Loss
(OHL) on Workers Lives
Family Life:
Disturbed family
interactions
Increased tension, stress,
frustration, anger and resentment frustration, anger and resentment
because of hearing difficulties
For example, being asked to
repeat things
-
Why is Occupational Noise Often Viewed
as a Low Risk Health Hazard?
Slow progression of noise induced hearing loss (lack of awareness by those affected in its early stages)
Strong tendency to conceal signs of hearing loss in the
workplace it is kept secret by those affected
Misperception that few workers are affected as a result, no Misperception that few workers are affected as a result, no
demands are made to reduce noise levels
Misperception of the effects of occupational hearing loss
perceived low level of impact on everyday life
-
What Does Hearing Loss Sound Like?
-
The Hearing Video
-
Provincial Legislation
-
NL Occupational Health & Safety Regulations 2009
Section 68 - Noise Hazards (see appendices)
(1) When a worker is required to work in an area in which noise levels
exceed the criteria for permissible noise exposure established by the
ACGIH Noise Threshold Limit Values (TLVs)
85dBA for an 8 hour workday
(a) the employer shall first take appropriate action to implement
control measures to reduce noise to acceptable levels; and
(b) where it is not practicable to reduce the noise to acceptable
levels or to isolate workers from the noise, the workers shall
wear personal protective equipment in accordance with CSA
Z94.2 Hearing Protection Devices Performances,
Selection, Care and Use.
-
NL Occupational Health & Safety Regulations 2009
Section 68 - Noise Hazards
(2) Where conditions referred to in subsection (1) exist, an employer
shall establish and maintain a hearing conservation program.
(3) A hearing conservation program established under subsection (2)
shall comply with the following minimum requirements:
(a) a noise survey of the workplace to identify high noise areas
shall be performed in accordance with CSA Z107.56
Procedures for Measurement of Occupational Noise
Exposure;
(b) hearing tests for every worker exposed to noise levels in
excess of permissible levels
-
NL Occupational Health and Safety Regulations 2009
Section 68 - Noise Hazards
(c) a hearing test , within 3 months of commencement of
employment
(d) mandatory training and education for all workers in the
health hazards of noise and the fitting, maintenance, care
and use of hearing protection.
(4) A hearing conservation program shall be documented and those
records shall be kept by the employer or the employer designate records shall be kept by the employer or the employer designate
while the worker remains employed by the employer.
(5) An employer shall post and maintain signs at entrances to or on the
periphery of areas where persons are exposed to high noise levels
in excess of the threshold limit.
-
Signs
-
NL Occupational Health & Safety Regulations 2009
Section 68 - Noise Hazards
(6) A sign referred to in subsection (5) shall clearly state that a
noise hazard exists and shall describe the personal
protective equipment that is required
(7) Upon termination of employment, a worker may request (7) Upon termination of employment, a worker may request
from the employer a record of noise exposure during the
term of employment
-
Federal Legislation
-
Canada Occupational Health and Safety Regulations
PART VII - LEVELS OF SOUND (see Appendices)
Sections include:7.1 Definitions
7.2 Measurement and Calculation of Exposure
7.3 Hazard Investigation
7.4 Limits of Exposure (87dBA for 8 hr workday)
7.5 Reduction of Sound Exposure7.5 Reduction of Sound Exposure
7.6 Report to Regional Health and Safety Officer
7.7 Hearing Protection
7.8 Warning Signs
-
CSA Standards Referenced in
OHS Regulations
Procedures for the
Measurement of
Occupational Noise
Exposure (Standard:
Z107.56-06)
Hearing Protection Devices Hearing Protection Devices
- Performance, Selection,
Care, and Use
(Standard: Z94.2-02 (R2007)
-
What are the Noise Exposure Limits in Canadian Jurisdictions?
Jurisdiction (federal, provincial, territorial)
Continuous Noise Impulse / Impact Noise
Maximum Permitted Exposure Level for 8 hrs: dB(A)
Exchange Rate dB(A) +
Maximum Peak
Pressure Level
dB(peak)
Maximum Number of Impacts
Canada (Federal) 87 3 - -
British Columbia 85 3 140 -
Alberta 85 3 - -
Saskatchewan 85 3 - -
Manitoba 85 3 - -
Ontario(includes ceiling level of 140 dBC)
85 3 - -
Quebec 90 5 140 100
New Brunswick 85 3 140 -
Nova Scotia 85 3 140 100
Prince Edward Island 85 3 - -
Newfoundland(references ACGIH TLVs)
85 3 - -
Northwest Territories 85 5 140 100
Nunavut 85 3 or 5* 140 -
Yukon Territories 85 3 140 90
-
Units of MeasurementDecibels (dB)
Noise is measured in units called "decibels" (dB)
Unit of measurement used to express *sound pressure levels
Sound Pressure Level: A measure of the loudness of sound,
measured in decibels (dB). Sound pressure level is related to
the sound energy entering the ears of an exposed person.the sound energy entering the ears of an exposed person.
The higher the decibel, the louder the noise
-
Decibels and A-weightingdBA
Sensitivity of the human ear to sound depends on the
frequency of the sound
People hear high frequency noise better than low frequency
noise
Noise measurement readings can be adjusted to correspond
to this peculiarity of human hearing
Decibels measured with an A-weighted filter are called dBA
(0 140 dBA)
0 dBA Threshold of hearing
130 dBA Threshold of pain
-
Decibels and A-weightingdBA
Legislation on workplace noise normally gives exposure limits
in dBA
A-weighting gives a scale for noise levels as experienced or
perceived by the human ear
dBA Lex:dBA Lex:
The level of a workers total exposure to noise in dBA, averaged over
the entire workday and adjusted to an equivalent 8hr exposure
Eg. A worker who works in an average of 85dBA of noise for 16 hrs
has an Lex of 88dBA, and for 4 hrs an Lex of 82dBA
-
Typical Noise Levels
Typical Noise Levels
Noise Source dB(A)
pneumatic chipper at 1 metre 115
hand-held circular saw at 1 metre 115
textile room 103
newspaper press 95
power lawn mower at 1 metre 92
diesel truck 50 km per hour at 20 metres 85
passenger car 60 km per hour at 20 metres 65
conversation at 1 metre 55
quiet room 40
* These are examples only.
Sound level measurements should be done to
confirm sound levels in the workplace.
-
What are the basic rules
of working with decibel (dB) units?Table 3
Decibel (dB) basics
Change in dB Change in sound energy
3 dB increase Sound energy doubled
3 dB decrease Sound energy halved
10 dB increase Sound energy increased by factor of 10
10 dB decrease Sound energy decreased by factor of 10
20 dB increase Sound energy increased by factor of 100
20 dB decrease Sound energy decreased by factor of 100
-
Table 1BNoise Exposure Limits when Criterion Level = 85 dB(A)
3 dB(A) Exchange Rate Maximum Permitted Daily Duration (hours)
5 dB(A) Exchange Rate
Allowable Level dB(A) Allowable Level dB(A)
85 8 85
88 4 90
91 2 9591 2 95
94 1 100
97 0.5 105
100 0.25 110
-
How Can I Tell If My Workplace Is Too Loud?Do people have to raise their voices?
Do you have difficulty communicating with another person at a distance of 1m?
If you need to raise your voice to be heard, then the noise level is high enough to cause hearing loss
Do people who work in noisy environments have ringing in their ears at the end of a shift?
Do people have to increase the volume on their car radio at the end of a Do people have to increase the volume on their car radio at the end of a shift higher than they did when they went to work?
Does a person who has worked in a noisy workplace for years have problems understanding conversations at parties or restaurants, or in crowds where there are many voices and competing noises?
-
Guidelines on Exposurefor Shifts Longer than 8 hours
Most standards and guidelines concerning noise exposure
limits are based on an 8-hour work shift (eg. NL - 85dBA)
Extended work shifts are common (eg. 12-hour shift)
Calculate the noise exposure for longer shifts using the 8
hour time-weighted average (TWA) noise exposure level in hour time-weighted average (TWA) noise exposure level in
dBA
-
Noise Control Techniques
Noise control at the source
Control of the transmission
path
Use of noise protective
measures at the receivermeasures at the receiver
-
Noise Control at the Sourceto reduce the generation of noise into the surrounding environment where workers are exposed
Elimination/removal of noise generating machinery/equipment from the workplace
Purchase/rental of quieter equipment and machinery
(look for low noise design)
Arrange proper installation with suppliers (eg. methods of mounting and location to ensure machinery operates as quietly as possible)
Vibration elimination (eg. balance rotating parts)
-
Noise Control at the Source
Enclosure of motors/equipment
Regular maintenance of machinery/equipment
(increase in noise with time in equipment with many parts due to
wear/poor maintenance)
Change processes
(e.g. relocate noisy machinery, suspend or reduce equipment operation at (e.g. relocate noisy machinery, suspend or reduce equipment operation at
scheduled times if possible when workers are present)
Turbulence suppression (use lower velocity/larger diameter ducts/pipes, progressive bends, fit silencers on intakes/exhausts)
-
Engineering Noise Control Solution
Problem: Compressed air for removal of fish scraps
An open pipe was used to direct compressed air to blow the fish scraps off a
fish-filleting machine. The noise level associated with this was 102dB
Solution
The open pipe was replaced with a special stainless steel low noise blowing
nozzle
ResultResult
The noise levels were reduced by 23dB to 79dB and the blowing force was
more than sufficient to keep the filleting machine free of scraps
-
Engineering Noise Control Solution
Problem: Transfer of components using a conveyor and metal chute
A manufacturer of tube fittings used conveyors to transport components
through the manufacturing process, and to deposit components into hoppers.
In one case the metal products would drop 3m, partly along a metal delivery
chute, before landing in the hopper. The noise level associated with this was
96dB
Solution
The angle of the conveyor was reduced, to reduce the drop height and the
section of the delivery chute was removedsection of the delivery chute was removed
The face of the chute was lined with a sheet of plastic
Result
The noise level was reduced by 7dB to 89dB
-
Engineering Noise Control Solution
Problem: Transfer of components using a bowl feeder
A manufacturer of tube fittings made extensive use of vibratory bowl feeders
to move metal products around and to transfer them from a hopper to the next
stage of a production process. The noise level associated with this was 96dB
Solution
The inside surfaces of the bowl feeder were faced with a 3mm thick layer of The inside surfaces of the bowl feeder were faced with a 3mm thick layer of
rubber held in place with a contact adhesive
Result
The noise level was reduced by at some 5dB to 91dB
-
Control of the Transmission Path
to reduce the energy that is communicated to the receiver
Increase the distance between the source and receiver
Doubling the distance reduces noise exposure by 6dB
Building layout
Barriers or partial enclosures Barriers or partial enclosures
Use of sound absorption (acoustical materials on ceiling/walls)
-
Protective Measures at the Receiver
employed where the noise level at the receiver is excessive
Hearing protection devices (ear plugs, ear muffs, and helmets)
Sound proof booths
Hearing conservation programs and education
Exposure control
Rotation of personnel reduces duration of exposure
-
Hearing Conservation ProgramsRequirement in legislation
The primary goal is to prevent noise induced hearing loss
resulting from occupational noise exposure
Required when noise in the workplace cannot be eliminated
and has been defined as hazardous
Options:Options:
In-house programs
On-site consultative and mobile services
Off-site consultative programs
Combinations of the above
-
Features of Hearing Conservation Programs
Noise surveys and identification of exposed workers
(Risk Assessment)
Sound level measurements at the worksite
Personal dosimeter measurements to determine worker
exposure/dose
Pre-employment and periodic audiometric testing for each
worker exposed to noise in excess of permissible levelsworker exposed to noise in excess of permissible levels
Annual testing (NL OHS Regulations)
Professional review of audiogram results by qualified personnel (compare with unexposed population of same age)
-
Features of Hearing Conservation Programs
Noise abatement
Engineering measures
Administrative measures (eg. Rotate workers from high to low noise areas)
Provision of appropriate personal hearing protection
Annual education and training for exposed employeesAnnual education and training for exposed employees
Health hazards of noise
Fitting, maintenance, care and use of hearing protection
Records maintained
-
Hearing Protection Devices (HPD)
Hearing Protection Device
A personal device, also referred to as a hearing protector,
worn to reduce the noise level reaching the eardrum.
AttenuationAttenuation
The reduction in sound pressure level at the ear due to the
application of a hearing protector
-
Hearing Protection Devices (HPD)Which one is best?
No single hearing protector is appropriate for everyone
CSA Standard on Hearing Protectors provides the following
criteria to consider when selecting hearing protection:
Worker's noise exposure level
Hearing ability of the worker
Use of other personal protective equipment
Temperature and climate
Communication demands on the worker
Physical constraints of the worker or work activity
-
Hearing Protection Devices (HPD)
Several types of protectors (many variations within each type):
Earmuffs (cap-mounted)
Earplugs (foam, premoulded, formable, custom molded, semi-insert)
Helmets (recreational, military)
Not commonly worn in occupational settingsNot commonly worn in occupational settings
Designed primarily for impact protection
Specialized hearing protection may be required (due to communication and audibility needs eg. workers with hearing loss)
-
Ear Plugs
-
Hearing Protection Devices (HPD).....Earplugs
Placed into or against the entrance of the ear canal to form a
seal and block sound
Range of sizes often available
Life expectancies vary (single use, reusable)
Earplugs can be class A, B, C or grade 0,1,2,3,4
(level of noise reduction they provide)
-
Hearing Protection Devices (HPD).....Earplugs
Choosing earplugs
Try to have a trained person make the selection
You need the right size for your ear canal if a good seal is not
achieved, it wont protect your hearing
When a plug is properly fitted, your voice sounds lower and muffled to
you
Head movements, talking and chewing can loosen the plugs refit Head movements, talking and chewing can loosen the plugs refit
them several times during the day
Wash reusable earplugs and canal caps with sap and water
and keep them in a case
-
Hearing Protection Devices (HPD).....Earplugs
Care of plugs
Wash reusable earplugs and canal caps with soap and water
Keep them in a case
Replace reusable plugs when they become hard or cracked (usually every 6 months)
Custom mould earplugs can last many years
(replace if they feel loose)(replace if they feel loose)
Discard compressible plugs when they become dirty or hard
-
Ear Muffs
-
Hearing Protection Devices (HPD).....Earmuffs
Hard outer shell to bounce
sound away from the ear
Sound-absorbent cuff to
snugly fit head and stop
sound from leaking in
Earmuffs can be class A, B,
C or grade 0,1,2,3,4
(level of noise reduction they
provide)
-
Hearing Protection Devices (HPD).....Earmuffs
Essential that earmuffs fit properly
Follow manufacturers instructions
Ensure you make a good seal with cuffs
(attention to hair, glasses, etc.)
Earmuff care
Inspect regularlyInspect regularly
Replace if become hard or cracked
Check tension of the headband
(if too loose entire device must be replaced)
Never alter/damage earmuff it lets sound in
-
Hearing Protection Use
Hearing protectors must be
worn ALL THE TIME in order to get the full benefit
If hearing protectors are
removed only for a short
duration, the protection is duration, the protection is
substantially reduced
-
What Happens to the Protection Level When Hearing Protectors
are Removed for Short Periods of Time?
Maximum protection provided by non-continuous use of hearing protection
Percent time use Maximum Protection
50% 3 dB
60% 4 dB
70% 5 dB
80% 7dB
90% 10 dB
95% 13 dB
99% 20 dB
99.9% 30 dB
-
CSA Standards Referenced
in OHS Regulations
Procedures for the
Measurement of
Occupational Noise
Exposure
(Standard: Z107.56-06)
Hearing Protection Devices
- Performance, Selection,
Care, and Use
(Standard: Z94.2-02 (R2007)
-
CSA Standards Referenced
in OHS Regulations
Procedures for the Measurement of
Occupational Noise Exposure (Standard: Z107.56-06)
Edition Referenced/Current: 2006
Measuring workers noise exposure is an essential part of any hearing
conservation program in determining the risk of occupational hearing
loss
The Standard presents methods of measurement using sampling
techniques
Users of this Standard should be proficient in noise measurement
-
CSA Standard Z107.56-06
Procedures for the Measurement
of Occupational Noise Exposure
Content Highlights:
1 Scope
2 Reference publications
3 Definitions and symbols
4 Instrumentation
4.1.1 Integrating sound level meter4.1.1 Integrating sound level meter
4.1.2 Noise dosimeter
4.1.3 Sound level meter
4.3 Instrument selection
5 Operating Conditions
-
CSA Standard Z107.56-06
Procedures for the Measurement
of Occupational Noise Exposure6 Procedures
6.1 Measurement of noise exposure level
6.2 Survey repetition
6.3 Selection of measurement procedure
6.4 Using a dosimeter
6.4.1 Measurement duration
6.4.2 Number of measurement repetitions for individuals
6.4.4 Measurement procedures6.4.4 Measurement procedures
6.4.5 Calculations
6.5 Using an integrating sound level meter
6.6 Using a sound level meter
Etc.
7 Reporting
-
CSA Standards Referenced
in OHS Regulations
Hearing Protection Devices
Performance, Selection, Care, and Use
(Standard: Z94.2-02 (R2007)
Edition Referenced/Current: 2002
Engineering controls are recognized as the most effective way of
reducing noise hazards either at its source or along its pathreducing noise hazards either at its source or along its path
HPD shall be used when engineering and or administrative controls
fail to reduce noise to acceptable levels
HPD reduce noise at the receiver
-
CSA Standard Z94.2-02
Hearing Protection Devices
Performance, Selection, Care, and Use
Content Highlights:
1. Scope
2. Definitions
4. Materials (composition of HPD)
5. Requirements
5.1 Sound Attenuation Performance5.1 Sound Attenuation Performance
5.2 Compliance with Manufacturers Specifications
6. Test Procedures
6.1 Sound Attenuation Measurement
-
CSA Standard Z94.2-02
Hearing Protection Devices
Performance, Selection, Care, and Use
7. Packaging Information
8. Selection, Care, and Use: Overview and General Requirements
9. Selection of Hearing Protection Devices
9.2 Types
9.3 Sound Attenuation
9.5 Double Protection9.5 Double Protection
9.6 Overprotection
9.7 Effectiveness
9.8 Noise Exposure Levels and Selection of Hearing Protection
Devices
-
CSA Standard Z94.2-02
Hearing Protection Devices
Performance, Selection, Care, and Use10. Fit, Care, And use of Hearing Protection Devices
10.1 Awareness
10.2 Proper Fit
10.3 Proper Training
11. Implementation
11.2 Issuing of Devices11.2 Issuing of Devices
11.3 Inspection and Replacement
11.4 Posting of Noise Hazardous Areas
11.5 Need for Periodic Audiometric Tests
12. Specialized Hearing Protection Devices
-
Choosing Hearing Protection
Canadian Standards Association
rates hearing protection as Class
A, B, C, or Grade 0,1,2,3, or 4
depending on the amount of
noise reduction the protector
provides
Recommended class or grade of Recommended class or grade of
protection increases with noise
level
-
Selection of Hearing Protection Devices
Based on Grade and Noise Exposure in dBA
Recommended protection for an
8 hour noise exposure
Presuming a desired effective
exposure when HPD are worn of
Lex,8 = 85 dBALex,8 = 85 dBA
-
Selection of Hearing Protection Devices
Based on Grade and Noise Exposure in dBA
Class C or Grade 1 protection is
recommended for driving a heavy
truck (89dBA)
Class A or Grade 4 is
recommended for operating a pile
driver (104dBA)
Wearing double protection Wearing double protection
(earplugs and earmuffs) is
recommended for extremely high
noise levels
-
Hearing Protectors
Noise Reduction Ratings (NRR)
An estimate of the reduction of noise at the ear when protectors are worn
properly
Hearing protection devices are tested under ideal controlled conditions in
a laboratory
Discrepancy between how protectors are fit in the testing laboratory and
how users wear protectors in the real world
Actual noise attenuation achieved in the workplace is lower
Earmuffs Subtract 25% from the manufacturers labelled NRR
Formable earplugs Subtract 50% from the labelled NRR
All other earplugs Subtract 70% from the labelled NRR
-
Rod Stickman
-
* Get real time access to the information you needthe information you need
* Avoid a one-to-two day waiting period!
-
Featured Services:
Employer Report of Injury (Form 7)
Account management enhancements
Account information
Assessments
Claims costs
Get CONNECTed
Claims costs
Clearance letters
Worksite Information
OH&S Committee Minutes
-
Please take the time to complete the Please take the time to complete the
evaluation form provided at the back evaluation form provided at the back
of your booklet and leave it at your of your booklet and leave it at your
tabletable
-
Thank You!!!
For more information, please call WHSCC office nearest you:
St. John's Grand Falls(709) 778-1552 (709) 489-16001-800-563-9000 1-800-563-3448
Corner Brook(709) 637-27001-800-563-2772
-
Please visit our website at www.whscc.nl.ca
Our website contains information on:Prevention ServicesPRIMEErgonomicsCEO Leadership CharterSafework NLs Who Wants to Save a Life? Game ShowCONNECT
You can also access from our website:PublicationsPublicationsFormsPostersTraining Providers
See the resource tab in your booklet for an overview of additional information provided on our website
-
ResourcesProvincially Regulated Sectors
Occupational Health and Safety Act and Regulations
http://www.gs.gov.nl.ca/ohs/legislation_summary.html
Federally Regulated Sectors
Human Resources and Skills Development Canada site (information on sectors under federal jurisdiction)
http://www.rhdcc-hrsdc.gc.ca/eng/labour/overview.shtml
Canada Labour Code Part II Occupational Health and Safety
http://laws.justice.gc.ca/eng/L-2/index.html
Canada Occupational Health and Safety Regulations (Part VII: Levels of Sound)
http://laws.justice.gc.ca/eng/SOR-86-304/index.htmlhttp://laws.justice.gc.ca/eng/SOR-86-304/index.html
View CSA Standards Referenced in OHS Regulations
http://ohsviewaccess.csa.ca/
Canadian Centre for Occupational Health and Safety (Noise)
http://www.ccohs.ca/oshanswers/phys_agents/
-
ResourcesWorkSafe BC Hearing Loss Prevention
What is hearing loss prevention?
Hearing Loss Prevention Program
Construction Industry Hearing Loss Prevention
Noise Measurement
Occupational Noise Surveys
Hearing Protection
How do I develop a hearing loss prevention program?
And other resource information, publications and tools
http://www2.worksafebc.com/Topics/HearingLossPrevention/Home.asp
American Conference of Industrial Hygienists http://www.acgih.org/home.htm