need this study guide complete answers come from powerpoint
schkia
7_ergo_hazards1.pdf
1
Biological hazards
Microbiological
Bacteria - Legionella
Virus - WNV
Fungi - Histoplasma
Parasites - Malaria
Insects – Mosquito, tick
Plants
EHST 3060/61:
Environmental Issues in
Construction
To identify specific ergonomic hazards in
construction
To discuss the adverse effects of these
ergonomic hazards
To enumerate the tasks involved with
exposure to ergonomic hazards
To enumerate control strategies for
ergonomic hazard exposure
Ergonomic hazards in construction
Adverse effects of ergonomic hazards
Construction tasks associated with
ergonomic hazards
Control strategies to prevent exposure to
ergonomic hazards
Physical
Chemical
Biological
Ergonomic
Occupational
Disease
The science of fitting workplace
conditions and job demands to the
capabilities of the working population
The scientific study of the relationship
between man and his work environment
to achieve optimum adjustment in terms
of efficiency, health and well-being
2
“Fitting the job to the worker”
Work Worker
To decrease risk of injuries and illnesses
To improve worker performance
To decrease worker discomfort
To improve the quality of work life
- AIHA Ergonomics Committee
Enhanced safety and health performance
Improved quality and productivity
Reduction in errors
Heightened employee morale
Reduced compensation and operating
costs
Accommodation of diverse populations
(i.e. disabled)
- AIHA Ergonomics Committee
Psychologists
Cognitive Scientists
Physiologists
Biomechanicists
Applied Physical
Anthropologists
Industrial
Hygienists
Safety Specialists
Occupational and
Systems Engineers
Musculoskeletal disorders
Other effects
Eye strain
Headache
Psychological stress
Boredom
Disorders of the muscles, nerves,
tendons, ligaments, joints,
cartilage, or spinal discs
Not typically the result of any
acute event but reflect a more
gradual or chronic development
3
Hand and wrist
Shoulders
Neck
Upper back
Lower back
Hips
Knees
Carpal tunnel syndrome
Raynaud’s phenomenon or White Finger
Disease
Tendinitis
Carpet Layers’ Knee
Back pain
http://experiencingrheumatoidarthritis.blogspot.com/2012/08/prepatellar-bursitis.html
The number of back injuries in U.S. construction was 50% higher than the average for all other U.S. industries in 1999 (CPWR, 2002).
Backaches and pain in the shoulders, neck, arms, and hands were the most common symptoms reported by construction workers (Cook et al, 1996).
Material handling incidents account for 32% of workers’ compensation claims in construction, and 25% of the cost of all claims. The average cost per claim is $9,240 (CNA, 2000).
Repetitive, forceful, or
prolonged exertions of the hands
Frequent or heavy lifting,
pushing, pulling, or carry heavy
objects
Prolonged awkward postures
Vibration
Cold
4
The level of risk due ergonomic
hazard exposure depends on:
Intensity of exposure
Frequency of exposure
Duration of exposure
Among the most prevalent lost-
time injuries and illnesses
Among the most costly
occupational problems
In diverse workplaces and job
operations
Cause a great deal of pain and
suffering
May decrease productivity and
the quality of products and
services
WMSDs of the upper
extremities
WMSDs of the lower
back
Food processors
Automobile and electronic assemblers
Office data entry workers
Carpenters
Affects the soft tissues of the
Neck
Shoulder
Elbow
Hand
Wrist
Fingers
Carpal tunnel syndrome
Cubital tunnel syndrome
deQuervain’s syndrome
Epicondylitis
Ganglion
Neck tension syndrome
Pronator syndrome
Shoulder tendinitis
Tendinitis
Tendo synovitis
Thoracic outlet syndrome
Trigger finger
Ulnar artery aneurysm
Ulnar nerve entrapment
White finger
5
Carpal tunnel
Area in your wrist where the nerve
enters the hand
Normally narrow, thus any swelling can
pinch the nerve
Pressure on the median nerve in the wrist
that supplies feeling and movement to the
thumb and "thumb-side" of the hand
Can lead to numbness, tingling, weakness, or
muscle damage in the hand and fingers
May result from repetitive motion of the
hand and wrist
High risk tasks:
Typing on a computer keyboard
Sewing
Driving
Assembly line work
Painting
Writing
Use of hand and vibrating tools
Sports (i.e. racquetball or handball)
Playing some musical instruments
Injury characterized by inability to bend or
straighten a finger due to a locked or
immobile tendon
Associated with the use of trigger-operated
tools
Repetition
Forceful motion
Awkward posture
Static loads
Mechanical stress
Low Temperatures
Vibration
Performing the same or similar movement
over and over without breaks, rest, or time
for recovery
Produce fatigue and muscle-tendon strain
A task cycle time of <30 seconds
Controls:
Work enrichment
Increase rest allowances
Worker rotation
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High-Risk Repetition Rates by Different
Body Parts
Body Part Repetitions per Minute
Shoulder More than 2.5
Upper arm/ elbow More than 10
Forearm/ wrist More than 10
Finger More than 200
Exertion of a significant amount of
strength to perform a task or use a tool
Controls:
Reduce weight of tools
Handle smaller quantities
Control balance of objects
Use or develop mechanical aids
Use of skid plates to move
charged concrete hoses
http://www.cdc.gov/niosh/docs/2007-122/materials.html
Working in awkward positions such as
bending, stooping, twisting, and overhead
reaching
Function of the:
Location and orientation of the work
Design of tools used
Extreme postures can lead to:
Discomfort and joint stresses
Reduced blood flow
High muscle forces
Fatigue
Reduced endurance time
Hands above mid-chest
height
Elevated shoulders
7
Control:
Work location
Work orientation
Better design of tools
To reduce awkward postures:
Hands not above mid-chest height
Shoulder not elevated
Shoulder abduction <30
Shoulder flexion minimized
Overhead reaches minimized
Shoulder Flexion
Shoulder abduction
Use of adjustable work stations
http://www.cdc.gov/niosh/docs/2007-122/overhead.html
Use a bit extension shaft
for the drill or screw gun
Same position for extended periods with little or no movement
High energy requirement
Low blood circulation
Controls:
Change posture
Bring load closer to body
Use mechanical jigs
Continuous pressure from a hard surface or
edge on any part of the body
Result: Reaction stress to the underlying
tendons
Control measures:
Work breaks
Work rotation and enrichment
Use of well-designed tools*
Use of PPE*
8
Use of power caulking gun
Using non-powered
caulking gun
http://www.cdc.gov/niosh/docs/2007-122/hand.html
Use a portable kneeling creeper
with chest support
http://www.cdc.gov/niosh/docs/2007-122/floor.html
Hand exposure to temp <65F
Effects:
Numbness
Decreased blood flow
Diminished sensory feedback
Controls:
PPE
Material temperature
Environmental temperature
Air exhaust
Sitting on, standing on, or holding equipment that vibrates
Factors:
Frequency and magnitude of vibration
Duration of exposure
Temporal exposure pattern and work method
Posture of hand
Type of tool
Effects:
Numbness of fingers
Wrist pain
Sensitivity to cold
Circulatory disturbances in fingers
Controls
Change process
Change tool*
Change operating
parameters
Work rotation and
enrichment
Work breaks
Use of PPE*
Use of high-
vibration tools
Use of anti-
vibration gloves Use of low-
vibration tools
Construction laborers
Carpenters
Truck and tractor operators
9
Awkward Posture
Frequency/Repetitive Handling
Static work
Roofer
Controls:
Keep loads to be lifted between knee and heart
height
Keep loads close to body when lifting
Avoid extreme range of motion when lifting
Avoid twisting when lifting loads
http://www.cdc.gov/niosh/docs/2007-122/floor.html
Use a rebar-tying tool Hand tying rebar
Results to constant
strain on the lower
back
Controls:
Mechanize task
Use “buddy” system
Prolonged standing or sitting
Controls:
Redesign work station to allow freedom
of movement
Have adjustable work station to allow
changes in posture
Remove physical barriers so worker can
stand closer to work
10
Different types of construction
work are often associated with
different types injuries.
Workers who do overhead work
(i.e. painters, sheet metal
workers, scaffold erectors)
shoulder and neck problems
Workers who work at floor level
and kneel while working (i.e.
floor layers and roofers,
carpenters) knee problems
Different types of construction
work are often associated with
different types injuries.
Workers who require constant use
of hand tools (i.e. carpenters)
hand and wrist problems
Workers who use vibrating hand
tools (i.e. lumberjacks, jack
hammer) Raynaud’s
phenomenon
Different types of
construction work are
often associated with
different types injuries.
Carpenters, electricians and
sheet metal workers
carpal tunnel syndrome
Workers who do heavy lifting
and carrying (i.e. laborer,
scaffold erector) back
problems
http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html
http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html
11
http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html
http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html http://www.dir.ca.gov/dosh/dosh_publications/erg_carpframer.html
http://www.cdc.gov/niosh/docs/2007-122/pdfs/2007-122.pdf
• Repetitive motion?
• Forceful motion?
• Heavy lifting,
pushing, pulling?
• Static/ Prolonged
posture?
• Awkward posture?
• Vibration?
• Cold?
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• Repetitive motion?
• Forceful motion?
• Heavy lifting,
pushing, pulling?
• Static/ Prolonged
posture?
• Awkward posture?
• Vibration?
• Cold?
Ergonomics is fitting the work to the worker.
Ergonomic hazards may result to MSDs of the upper extremities and lower back.
Different construction tasks are associated with different MSDs.
Good work practices may reduce stress on the muscles, thus reducing risk of developing MSDs.
Mark A. Friend and James P. kohn.
Fundamentals of Occupational Safety and
Health, 2nd ed., Chapter 7
Preventing Muskuloskeletal Disorders in
Construction Workers.
http://www.elcosh.org/en/document/581/d
000560/preventing-muskuloskeletal-
disorders-in-construction-workers.html
