postural strain and occupational hazards

1. Dr.Priyanka Patel
M.P.T. (Musculoskeletal and sports)
1
Postural strain and occupational
hazards

2. Occupational health
 refers to the potential risks to health and safety for
those who work outside the home
Hazard
 something that can cause harm if not controlled.
Occupational disease
 Disease directly caused by a person’s occupation.
Workplace
 setting in which many people spend the largest
proportion of their time.
 exposes many workers to health hazards
2

3. Occupational Environment
Three types of interactions in the work place:
Man and physical, chemical, & biological
agents.
Man and machine.
Man and man.
3

4. COMMON CAUSES:
4
 Repetitive/prolonged activities –constant
lifting, continuous pressing/pulling with same
extremity, even prolonged sitting especially
with poor posture.
 Awkward positions including reaching above the
shoulders or behind the back, twisting the wrists &
other joints, twisting at the waist.
 Vibration from power tools(jackhammer)-excessive
vibration causes pain to muscles, joints, causes trauma
to the hands, arms, feet & legs.

5. 5
 Temperatures -Excessive heat and humidity effects
the body’s blood circulation and causes cramps and
general discomfort. Cold exposures effects the body’s
blood circulation and causes hypothermia & loss of
flexibility. A general comfortable temperature range is
68-74 degrees F +/-10 degrees depending on work load
.
 Forceful exertions – the greater the amount of force
that is applied, the greater the degree of risk for a MSD
to occur. Examples of Work Related MSD injuries that
are associated with “High Force” are at the
shoulder/neck, the low back, and forearm/wrist/hand.

6. Risk Factors
6
Repetition
Force
Static Loading

7. 7
 Awkward Posture: Any position where a body
segment is angled outside the mid-point range of
motion for that joint
 Force: amount of effort needed to lift, carry, push,
pull, or grip an object
 Repetition: number of motions (awkward postures)
performed by a body segment; thresholds are body
segment dependent and typically multiple
repetitions per minute
 Static Loading: maintaining an awkward posture
without external support for a prolonged period of
time
 Contact Stress: compression of soft tissue with
any hard or sharp surface
 Vibration: whole body or body segment vibration

8. OCCUPATIONAL HAZARDS
I. Physical
hazards
II. Chemical
hazards
III. Biological
hazards
IV.
Mechanical
hazards
V.
Psychological
hazards
8

9. OCCUPATIONAL HAZARDS
Physical hazards
Heat – Direct & indirect effect of high temperature,
radiant heat.
Cold – General & local cold injury
Light – Acute & chronic effect of bright & dim light &
glare.
Radiation
a. Ionizing - X-rays,gamma rays,beta particles, alpha particles
b. Non-ionizing - microwaves, infrared, and ultra-violet light
Noise – Auditory & non auditory effect.
Vibration – hazardous in the frequency range of 10-
500Hz
9

10. Diseases due to Physical agents
Heat – Heat stroke, Heat hyperpyrexia, Heat
syncope, Heat rash.
Light – Occupational cataract
Cold – Hypothermia, Frost bite, Trench foot.
Pressure – Air embolism, Blast injuries.
Vibration – Osteoarthritis, Reynauds
disease [white fingers]
Noise – Occupational deafness.
Radiation- Cancer, genetic changes,
Aplastic anaemia.
10

11. Mechanical hazards
 Unsafe/ inadequate equipment
 Lifting devices and lifting heavy loads.
 Slippery floors
 Repetitive motions.
11

12. 1. Repetitive Strain Injuries
2. Carpal Tunnel Syndrome
3. Eye Strains and Computer Vision
Syndrome
4. Stress and Depression
5. Radiation
12
Computer Related Health
Hazards

13. Carpal Tunnel Syndrome
13
 Carpal Tunnel Syndrome (CTS) is a Repetitive
Stress Injury (RSI) caused when the median
nerve is pushed by the flexor tendons inside the
tunnel made up of the wrist bones, or carpals.
SYMPTOMS :-
 Pain that may run up the hand into the wrist and
arm
 Numbness and coldness in the hands
 Loss of strength and/or joint movement
 Discomfort and stiffness in the hands
 The need to massage your hands, wrists and
arms
 Swelling and coldness in the hand

14. CTS Treatment
14
 Rest, rest and more rest
 Use of a wrist brace or splint
 Take medication like ibuprofen
 Cut back on sugar, caffeine, alcohol and take vitamins
 Keep hands warm, take breaks, exercise your hands
and arms
 Correct your typing and use your knowledge of
ergonomics
 Surgery should be your last retreat if everything else
fails

15. Eye Strains
15
 Eye strain is the single largest complaint of Video
Display Terminal users causing soreness,
irritation, blurred vision, redness, dryness and
tenderness of the eyes.
Symptoms:-
 Impaired vision, double vision and blurred vision
 Difficulty looking at one point for a period of time
 Itchy dry eyes
 Headaches
 Eye fatigue that can have serious impact later in
life

16. Reasons for this injury
16
 Bad monitor resolution or glare at the monitor
 Poor lighting conditions in the computer room
 Electromagnetic radiation emitted by the VDT (UVA)
 Staring at anything for a long period of time will cause
blurred vision
Eye Strain Treatment
 Use your knowledge of ergonomics
 Take breaks when you feel strained
 Use your laptop when possible because the monitor
emits less radiation
 Adjust the brightness of your screen
 Wear protective eye glasses

17. A few ergonomic advice
17
 Use a chair that has full support of your back, is adjustable,
and has a footrest and armrest
 Use an ergonomic keyboard that is angled or can split to enjoy
a more natural typing position
 Use a wrist rest that is comfortable and Place your hands
straight when typing, the angle of your forearm and upper arm
should be 90 degrees
 Sit 24 to 28 inches away from your monitor
 Place the monitor 15-30 degrees below your straight-ahead
line of sight
 Keep your body away from the sides and backs of monitors to
reduce the exposure of radiation
 Avoid glare on your monitor (do not have strong sources of
light in your back) and use screens that minimize glare
 Use the proper light in your work environment that is

18. To minimize injuries due to chronic
physical and psychological stresses,
while maximizing productivity and
efficiency
18
PROGRAM GOAL

19. Definition: 4Ps.
 Aims at the PROMOTION AND MAINTENANCE of the highest
degree of physical, mental and social well being of workers in all
occupation;
 the PREVENTION of ill-health among workers caused by their
working conditions;
 the PROTECTION of workers in their employment from risk
resulting from factors that adversely affect health;
 the PLACING AND MAINTENANCE of the worker in an
occupational environment adapted to his physiological and
psychological ability.
19

20. WHAT CAN WE DO?
20
 Administrative controls
 Work practice controls
 Engineering controls

21. ADMINISTRATIVE CONTROLS
21
1. Employee rotation/job task enlargement-if possible rotate employees
between job tasks so that an employee is assigned to perform one task then
moved to another.
2. Adjust work place-
3. Redesign the work - Is there a better way to do the task with less stress, strain,
is there a tool or piece of equipment that could be used to help perform the task.
4. Alternative task- Whenever possible have employees alternative their tasks
frequently throughout the day. Rotate heavy and/or repetitive tasks with lighter,
less repetitive tasks.
5. Breaks-Encourage employees to change position, stand up or stretch whenever
they start to feel tired.
6. static vs the dynamic work positions and that muscles fatigue easier when
held in the same position for extended periods of time. Encourage motion
rather than static positions. It is recommended that you take 1 or 2 minute
breaks every 30 minutes and 5 minute breaks every hour when performing
stationary type work.

22. WORK PRACTICE CONTROLS
22
 Safe & proper work techniques & procedures
 Training
 Physical conditioning period
1. Safe and proper work techniques and procedures for performing the
job tasks. The work techniques could include proper positions and angles
when sitting at your computer station to standing and performing tasks.
2. Training recognition of hazards and work techniques that can reduce
exposure or ease task demands and burdens.
3. Conditioning period for new or reassigned employees to learn the work
techniques and procedures. Supervise the employees performing the
tasks to ensure understood the training and are performing correctly. If
not provide additional training.

23. POSTURE & ANGLES
23
 Whether your tasks are performed while sitting or standing,
always maintain proper posture & angles--and avoid:
Awkward positions, and
Extreme reaches for materials
BODY ANGLES
 HEAD
 SHOULDERS
 ELBOWS
 HANDS
 WAIST
 LEGS
 FEET

24. ENGINEERING CONTROLS
24
 Workstations
 Tools/equipment
 Facilities

25. WORKSTATIONS
25
The objective is to:
 Fit the workstation to the employee
 Reduce awkward positions
This can be done by using two methods:
Standard Way
 Adjustable
workstation
 Adjustable chair
 Foot rests
 Adjustable monitor
 Document holder
Innovative Way
 Add blocks
 Build foot rest
 Thick book
 Build platform

26. TOOLS
Use of Force or of grip-strength
Longer/shorter and thicker/thinner
handles
26
 Repetitive motion
 Ratcheting
mechanism or gears
 Power tools
 Electric stapler
 Electric knife
 Awkward positions
 Bent or curved
handles
 Headphones
 Support equipment
overhead

27. TOOLS CONT.
27
 Forceful exertions
 Soft-touch
keyboards/button
s
 Lifting devices
 Static positions
 Anti-fatigue mats
 Vibration
 Anti-vibration
materials
 Anti-vibration
mounts/handles
 Anti-vibration
gloves

28. FACILITIES
28
 Lighting/glare

29. Tips to Minimize Awkward Postural strain
29
 Avoid overhead
reaching and kneeling
when possible
 Work near elbow height
to avoid bending
excessive bending

30. Tips to Minimize Awkward Postural strain
30
 Where awkward
postures are
unavoidable, change
tasks, stretch, and take
short breaks frequently

31. Tips to Minimize Force
31
 Use mechanical lift assists and carts
when available
 Avoid manually handling heavy
objects (more than 35 pounds)
 Avoid carrying objects more than
100 feet
 Practice Proper Cart Handling
 Push instead of pulling
 Use both hands when pushing
 Stand directly behind the cart
when pushing
 Ensure cart is not overloaded

32. Tips to Minimize Force
32
 Use proper lifting techniques
when lifting
 Bend knees when lifting a
load
 Look forward to keep back
straight
 Position the load close to the
body
 Maintain a firm grip on the
load
 Use smooth, controlled
movements
 Keep arms in front of body
 Turn feet in direction of
movement to avoid twisting

33. Tips to Minimize Force
33
 Use the correct tools /
powered tools for the task
 Powered tools tend to
require less exertion to
perform a task
 Ensure that the weight of a
powered tool (and cording)
does not create additional
force issues
 Use only the amount of force
necessary to complete the

34. Tips to Minimize Repetition
 Repetition:
 Use power tools when
available
 Change tasks, stretch, or
take a break from
repetitive tasks
 Follow job rotation policies
where applicable –
effective job rotations work
alternate muscle groups

35. Tips to Minimize Static Loading
 Static Loading:
 Avoid prolonged awkward
postures
 Change the position of the
work or your body position
to get as close as possible
to the work area
 If prolonged awkward
postures are unavoidable,
use a “supported” posture to
compensate
 A supported posture uses
part of your body to support

36. Tips to Minimize Contact Stress
36
 Avoid pressure on knees:
 Avoid kneeling on hard
surfaces for prolonged
periods
 Use knee pads when
kneeling tasks are
unavoidable
 Avoid pressure on palms,
wrists, and elbows:
 Use padding on hard or
sharp surfaces
 Change your position to
eliminate the stress

37. Tips to Minimize Vibration & Torque
37
 To lessen vibration:
 Pad tool handles with a soft
compressible surface
 Use vibration damping (gel
filled) gloves
 Select tools (hammers and
chippers) with built in
damping systems
(springs/hydraulics)
 To lessen torque reaction:
 Use electric tools as
opposed to air driven tools
 Use pulse tools or auto-
shutoff tools

38. EXERCISES & STRETCHES
38
 These are exercises or stretches that
can be performed at your workstation,
home, just about anywhere.

39. Stretching Basics
39
 Benefits of stretching:
 Increases flexibility/elasticity of
muscles
 Increases circulation to warm
the muscles, improving mental
alertness, reducing fatigue
 Decreases muscle tension and
stress
 When to Stretch:
 Prior to starting your day
 During short breaks (at least
once per hour)
 After breaks or lunch to prevent
fatigue
 If tension or stress is apparent
 After a lengthy task duration or
an extended awkward posture

40. Stretching Basics
40
 Proper stretching techniques:
 Relax and breathe normally. Do not
hold your breath.
 Hold each stretch for a count of 15, or
as long as comfort is maintained.
 Use gentle, controlled motions. Do
not bounce!
 Keep the knees slightly bent for better
balance.
 Stretch until a mild tension is felt, then
relax.
 Stretch by how you feel and not by
how far you can go.

41. EYE
41
 Eye comfort exercises
 Blinking
 Yawning
 Focus change
Note:-
•Blinking and Yawning both
produce tears to help moisten
and lubricate the eyes.
•Focus on a distance object
across the room or even outside
the window.

42. EYE Palming
42
 While seated, brace elbows on the edge of the
desk
 Let weight fall forward
 Cup hands over eyes and close eyes
 Inhale slowly through nose & hold for 4 seconds
 Continue deep breathing for 15-30 seconds

43. EYE Movements
43
 Close eyes and slowly & gently move eyes up
to the ceiling, then slowly down to the floor
 Repeat 3 times
 Close eyes and slowly & gently move eyes to
the left, then slowly to the right
 Repeat 3 times

44. NECK STRETCH
44
 Tilt ear towards shoulder
 Reach up and touch top of head with palm to
hold in tilted position
 Hold 5-10 seconds. Repeat 2-3 times (come
out of stretch slowly)
 Reverse side and repeat

45. Pec Corner Stretch
45
 Stand at a corner about a foot away from the wall
with forearms on opposite sides of the corner.
One foot should be forward.
 Elbows should be at slightly below shoulder height
 Keep abdominals tight to avoid arching back
 Lean gently towards corner by bending the front
knee until a stretch is felt in front of the chest.
 Hold 5-10 seconds. Repeat 2-3 times

46. Overhead Reach
46
 Take a deep breathe and reach up over head
with both arms.
 Hold 5-10 seconds
 Exhale and lower slowly
 Repeat 2-3 times

47. Shoulder Pinch
47
 Place arms behind head being careful not to press
hand into head
 Relax shoulders, and squeeze shoulder blades
together while keeping shoulders back and down
 Hold 5-10 seconds. Repeat 2-3 times

48. Shoulder Shrug
48
 Sitting up straight, slowly bring shoulders up
toward your ears.
 Hold positions 5-10 seconds
 Then bring the shoulders down and hold
 Repeat 2-3 times

49. Chair Rotation Stretch
49
 Sit in chair and place feet flat on floor
 Reach across your body and grab the back of the
chair
 Pull gently to increase stretch in mid back
 Hold 5-10 seconds. Repeat 5 times
 Repeat on other side

50. Arms Behind Back Stretch
50
 Hold hands behind back and grasp hands
together
 Pull shoulder blades back and down
 Hold 5 seconds. Repeat 5 times

51. Thoracic Spine Extension Stretch
51
 Lie on your back with a pillow under your knees.
Place a firmly rolled towel under your shoulder
blades across your upper back
 Raise arms up as you inhale
 Lower arms as you exhale, and hold a couple of
seconds
 Do this 5 times

52. Prop Ups or Press Ups
52
 Lie on stomach and either prop up on forearms or
if wrists are not compromised, press up through
hands.
 Let stomach sag, and allow back to arch without
using back muscles.
 If propped on elbows, hold 5-10 seconds. Repeat
5 times
 If on hands, press up and down slowly 10 times
Foot Rotations
 While sitting upright, slowly rotate each foot from
the ankles 3 times in one direction
 Then rotate 3 in the opposite direction

53. Wrist Flexed & Extended
53
 Hold arm straight at waist height With fingers of
other hand, gently press down above the
knuckles, bending wrist down. (DO NOT hold at
the fingers to push down.)
 Hold 5-10 seconds and repeat 2-3 times
 For extending, hold onto palm of hand and
stretch wrist back. (DO NOT pull on fingers.)
 Hold 5-10 seconds and repeat 2-3 times.

54. Finger Massage
54
 VERY gently, massage the fingers of each hand
individually.
 Move toward the nail gently.
 Massage the space between your fingers to
widen and relax
 Finger Squeeze
 Squeeze a foam block OR the edge of your desk
firmly with all fingers
 Hold for 3 seconds
 Relax your grip