Ergonomics Awareness Training

1
Ergonomics Awareness Training
Navy Ergonomics Program
Cathy Rothwell, PE Ergonomic Program Manager
rothwellcb_at_efdsw.navfac.navy.mil Mindy Smith,
MEng, AEP Ergonomic Technical Support - East
Coast smithmb_at_navfac.navy.mil Theresa Stack, MS,
AEP Ergonomic Technical Support- West Coast
stacktl_at_navfac.navy.mil
2
What is Ergonomics? ergonomics \,
ûrg-go-'näm-iks

• Ergonomics is derived from two Greek words
• Ergon meaning work
• and
• Nomos meaning principles or laws
• Ergonomics The Science of Work
• Ergonomics is not a new science, although the
  term has become more common lately. The phrase
  was first coined in 1857.

3
Common Definitions
What is Ergonomics? ergonomics \,
ûrg-go-'näm-iks

• Ergonomics is essentially fitting the workplace
  to the worker. The better the fit the higher the
  level of safety and worker efficiency. Fitting
  the Task to the Human Grandjean 1990
• Ergonomics removes barriers to quality,
  productivity and human performance by fitting
  products, tasks, and environments to people.
  ErgoWeb.com

4
What are the consequences of poor Ergonomics?

• Why are we hearing about ergonomics now? Are
  there new hazards at work? No!
• Consequences of poor workplace design were first
  documented in the 17th century.
• Have you ever heard of these?
• Historic Occupational Disorders - house-maids
  knee, washer womans thumb, writers cramp,
  data-processing disease, clergymans knee, nuns
  bursitis, weavers bottom, dustmans shoulder,
  tailors ankle

5
Do these historic occupational disorders still
exist? Yes!

• They are part of a broad category of injuries and
  disorders called Musculoskeletal Disorders
  (MSDs). MSDs are not usually caused by acute
  trauma, but occur slowly over time due to
  repetitive injuries to the soft tissues (muscles,
  tendons, ligaments, joints, cartilage) and
  nervous system
• MSDs can happen to anyone from office workers and
  industrial employees to athletes and hobbyists

6
Do these historic occupational disorders still
exist? Yes!

• Work-Related Musculoskeletal Disorders (WMSDs)
  are MSDs that are caused or made worse by work
  methods and environment. They occur when the
  physical capabilities of the worker do not match
  the physical requirements of the job
• Common MSDs
• Tendonitis, Epicondylitis (Tennis or Golfers
  Elbow), Bursitis, Trigger Finger, Carpal Tunnel
  Syndrome, Back Strain

7
What are aliases for WMSDs?

• Work-related MSDs go by many other names
• Repetitive Strain or Stress Injury (RSI)
• Repetitive Motion Injury (RMI)
• Cumulative Trauma Disorder (CTD)
• Overuse Syndrome
• Activity-related Pain Syndrome

Ergonomics can help prevent MSDs that are caused
or aggravated by working conditions
8
What characteristics of your job put you at risk
for MSDs?
Prolonged, repeated or extreme exposure to
multiple WMSD risk factors can cause damage to a
workers body. Risk Factors include

• Excessive Force
• Vibration
• Compression
• Inadequate Recovery

• Repetition
• Awkward Postures
• Static Postures
• Cold Temperatures

9
Repetition Performing the same motion or group
of motions excessively.

• Examples of Repetition

• Repeating the same motion every few seconds or
  repeating a cycle of motions involving the same
  body parts more than twice per minute for more
  than 2 consecutive hours in a row
• Using a tool or an input device, such as a
  keyboard in a steady manner for more than 4 hours
  total in a work day

Excessive repetition of movements can irritate
tendons and increase pressure on nerves
10
Awkward Postures Postures outside of neutral.

• Neutral is the optimal position of each joint
  that provides the most strength
• and control

Before Lab technician tilts his neck forward to
view the screen into a non-neutral posture. He
also bends over resting on his forearms to write
on the documents.
Ergonomic Improvement Sailor easily views the
screen from a neutral posture. The workstation
adjusts to accommodate different working heights
and users. When standing, work should be about
elbow height.
Awkward or unsupported postures that stretch
physical limits, can compress nerves and irritate
tendons
11
Awkward Postures Postures outside of neutral.

• Examples of Awkward Postures

• Repeatedly raising or working with the hand(s)
  above the head or the elbow(s) above the
  shoulder(s) for more than 2 hours per day
• Kneeling or squatting for more than 2 hours total
  per day
• Working with the back, neck or wrist bent or
  twisted for more then 2 hours per day
• Sitting with feet unsupported

12
Neutral Posture for Computer Use
Position the monitor about an arms length away
directly in front of you. The top of the screen
no higher than eye level (Unless the user wears
bi-focal glasses)
Adjust the seat height so upper arms hang
vertically, elbows bent about 90 degrees,
shoulders relaxed and wrists fairly straight
Use a document holder close to the monitor rather
than laying papers flat
Adjust the back rest to provide firm support to
the small of the back
Mouse should be next to keyboard both at a height
equivalent to the users seated elbow height
Knees comfortably bent with feet resting on the
floor. If the chair is raised so the keyboard
height equals elbow height, use a footrest .
13
Static Postures Holding the same position or
using the same muscles for extended periods of
time
Static postures, or positions that a worker must
hold for long periods of time, can restrict blood
flow and damage muscles
Before Mechanic maintains a static posture
holding arms and hands elevated while repairing
aircraft
Ergonomic Improvement Creeper supports mechanic
and brings him closer to the task
14
Cold Temperatures

• Working in environments below 68 degrees can
  cause nerve damage.

Working in cold temperatures can adversely affect
a workers coordination and manual dexterity and
cause a worker to use more force than is required
to perform a task
15
Force A strong physical exertion

• Exertion the tension produced by muscles and
  transmitted through tendons

Before Three sailors climb on refuse bin to dump
laundry cart full of waste. They risk back
strain and lacerations while tipping cart over to
empty it.
Excessive muscle tension can contract muscles to
their maximum capability which can lead to
fatigue and possible damage to the muscles and
other tissues.
Ergonomic Improvement One worker easily dumps
waste in half the time.

16
Force A strong physical exertion

• Examples of forceful exertions

• Lifting
• more then 75 pounds at any one time
• more then 55 pounds more than 10 times per day
• more then 25 pounds from a height below the
  knees, above the shoulders, or at arms length
  more than 25 times per day.
• Pushing / pulling with more than 20 pounds of
  initial force for more than 2 hours per day
• Pinching (pencil type grip) an unsupported object
  weighing 2 or more pounds per hand for more than
  2 hours per day
• Gripping an unsupported object weighing 10 pounds
  or more per hand for more than 2 hours per day

17
Vibration - Single Point

• Hand and Arm exposure results from vibrating
  objects such as power tools.

• Examples of vibrating tools
• Using vibrating tools or equipment that typically
  have high vibration levels for more then 30
  minutes a day (chain saws, jack hammers,
  percussive tools, riveting or chipping hammers).
• Using tools or equipment that typically have
  moderate vibration levels for more then 2 hours
  total per day (jig saws, grinders or sanders).

Before Sailor is exposed to vibration above
ACGIH TLV guidelines Ergonomic Improvement
Lower vibration tool reduces vibration to safe
levels
18
Vibration - Whole Body

• Whole Body exposure to vibration results from
  vehicles such as forklifts, cranes, trucks, buses
  subways and aircraft.

High or prolonged exposure to whole body
vibration can affect the skeletal muscles and
cause low- back pain
19
Compression soft tissue is compressed between
the bone and a hard or sharp object
Compression, from grasping or contacting edges
like tool handles, can concentrate force on small
areas of the body, reduce blood flow and nerve
transmission and damage tendons and tendon sheaths
Before Worker rests his wrists on the sharp tray
edges. His wrist is extended into a non-neutral
posture.
Ergonomic Improvement Worker rests her wrists
and forearms on a padded surface. Wrist and
forearms are in a neutral position.
20
Compression soft tissue is compressed between
the bone and a hard or sharp object
Compression, from grasping or contacting edges
like tool handles, can concentrate force on small
areas of the body, reduce blood flow and nerve
transmission and damage tendons and tendon sheaths
Before Tool handles are small and angular
requiring the worker to grasp tightly against
sharp edges
Ergonomic Improvement Tool handle is formed to
fit the workers hand which requires less grip
strength or force and a more user-friendly tool
21
Can Other Factors Contribute to MSDs?

• Not all ergonomic risk factors are physical, some
  are related to the work environment.

Stress on the job, peer pressure, boredom,
conflicts with co-workers and supervisors,
deadlines, and even a lack of control over what
you do can contribute to (but not cause) MSDs
22
Can Personal Factors Contribute to MSDs?
Some people are at greater risk of developing
MSDs due to personal factors

• Age and Gender
• Hobbies
• Previous Injuries
• Physical Condition
• Medical conditions (diabetes and arthritis)

• Obesity
• Medications
• Smoking
• Fatigue

23
What are MSD Signs and Symptoms?

• Painful aching joints, muscles
• Pain, tingling or numbness
• Fingers or toes turning white
• Shooting or stabbing pains
• Swelling or inflammation
• Stiffness or difficulty moving
• Burning sensation
• Pain during the night

24
What should you do if you experience a MSD Sign
or Symptom?

• If you experience signs or symptoms of MSDs,
  report it to a supervisor, industrial hygienist
  or safety professional
• If pain or discomfort does not go away when you
  leave work or interferes with you carrying out
  normal activities, see an occupational health
  physician

25
How do you Avoid MSDs? Work Smarter, Not Harder!

• Work in neutral postures
• Reduce excessive force repetition
• Keep everything in easy reach and at proper
  heights
• Keep warm
• Minimize static unsupported postures and pressure
  points

• Use proper lifting techniques and lift aides
• Ask for assistance with difficult tasks
• Take micro-breaks (stand, stretch, change tasks)
• Maintain a comfortable environment

26
What can ergonomics do for you?

• The anticipated benefits of good workplace design
• Improved health and safety by reducing
  work-related injuries and disorders
• Improved comfort, morale and job satisfaction
• Improved productivity and reduced workers
  compensation costs and employee turnover

Before Improved
27
Where to go for more information

• NAVFAC web site contains ergonomic tools,
  resources, guides, training and awareness
  material
• www.navfac.navy.mil/safety (Select - Program
  Categories - Ergonomics)
• NAVOSH website- Contains success stories of
  ergonomic interventions throughout the Navy
• www.navosh.net/ergonomics
• DoD Ergonomic Working Group - Contains Guide to
  Setting up an Ergonomics Program and many other
  tools
• chppm-www.apgea.army.mil/ergowg/index.htm
• NIOSH- order many free ergonomic documents
  including Elements of Ergonomics Programs and
  Cumulative Trauma Disorders in the Workplace
• www..cdc.gov/niosh/
• Navy Policy 5100.23G Chapter 23 Ergonomic
  Program