12 Ergonomics Principle

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Safety means

• S - SERIOUS

• A - ALERT

• F - FOCUSED

• E - EDUCATED

•T - TEAM MINDED

• Y - YOU



Implementing

Ergonomics Principles

at the Workplace

DR. AZMI SAMAT.

MD, Pg-DOH, MSc-OSH.



Objective

• Define ergonomics

• 12 Principles of ergonomics that

can be implemented at theworkplace.



What is Ergonomics?

• Derived from Greek words

• Ergon = work

• Nomos = law

ERGONOMICS = STUDY OF WORKS LAWS

Study of human abilities and characteristicswhich affect the design of equipment, systems

and jobs.



Goal of Ergonomics

- generate “tolerable ,“acceptable” and “optimal”

working conditions

Aim of Ergonomics

All man made tools, devices, equipment, machines& environment should advance directly, the safety,

well being and performance of humans.



[Part I - ll, Section 4 - 5]

OCCUPATIONAL SAFETY AND

HEALTH

Act 4.

4 (c) To promote an occupational

environment for persons at work

which is adapted to their

physiological and psychological

needs.



Twelve Principles of Ergonomics



12 principles of ergonomics

1. Work in neutral position.

2. Decrease excessive force

3. Keep everything in easy reach

4. Work at proper height

5. Decrease excessive motion

6. Minimize fatigue & static load



Cont.

7. Minimize Pressure points.8. Provide clearance

9. Move, exercise & stretch

10. Maintain a comfortableenvironment.

11. Make displays & controls

understandable12. improve work organization.



Principle 1 : Work in

Neutral Postures

Your posture provides a good starting

point for evaluating the task that you do.

The best positions in which to work are

those that keep the body in neutral.



• Maintain the “S-Curve” of the

Spine whether standing or sitting

• Standing-putting one foot up onfootrest helps to keep the spinal

column in proper alignment

• Sitting-lumbar support is helpful to

maintain the natural curve of back

• Bending-using lifter or tilter to avoid

bending at a lengthy time.

P1 : Work in Neutral Postures



Lumbar support?



• Keep the Neck

Aligned

• Prolonged twistedand bent postures

of the neck can

be as stressful as

its equivalent for

the lower back.• adjust equipment

so that your neck

is in its neutral

posture




• Keeps Elbows In and Shoulders

Relaxed

• Changing workstation to get armsin neutral position




• Keep Wrists in Neutral

• keep the hand in the same planeas the forearm

Pliers with angle grip

Principles applies to tool design

Using wrist rest

along with

computer mouse



Principle 2: ReduceExcessive Force

• Excessive force on your joints can

create a potential for fatigue and

injury. In practical terms, the action

item is for you to identify specific

instances of excessive force andthink of ways to make

improvements.



• reduce grasping force where

possible.

• minimize the arm force needed.

• keep loads as close to the body

as possible.

• reduce pulling and pushingforces.

P2: Reduce Excessive Force



• Pulling heavy

cart

• Improvements:

• Floor in good

repair

• Wheels are

sufficiently large

• Good grips on

the cart




• Hoist - lifting heavy objects• Handholds on boxes – reduce

exertion on hands




Principle 3: Keep Everythingin Easy Reach

This principle is redundant

with posture,

but it helps to evaluate a taskfrom this

specific perspective.



• "reach envelope."

• Things frequently

use - ideally be

within the reachenvelope of your full

arm.

•Things that is useextremely frequent -

within the reach

envelope of your

forearms.

P3: Keep Everything in Easy

Reach



Component arrangement

before improvement

After improvement



P3: Keep Everything inEasy Reach



• Reaching into boxes• good way to fix

this is to tilt the box.

• Point-figure out how toreduce making long reach.

P3: Keep Everything in EasyReach



P3: Keep Everything in

Easy Reach



Principle 4: Work at Proper

Heights

• Do most work at elbow height

• Rule of thumb - most work should be

done at about elbow height, whether

sitting or standing.

• Examples

• Computer work,

• assembly work• etc



• Exceptions to the Rule

• Heavy work - best done lower than

elbow height where downward

force is required for the task.

• Precision work / visually intensework - best done at heights above

the elbow.

P4: Work at Proper Heights



• Adjusting Height

• extending the legs toa work tables or cutting them down

• work platform on topof the table (to raisethe work up) or standon a platform (to raisethe worker up).

• Adjustable workingtable – hand cranks /push button controls.




Before improvement After improvement




Condition of tv display pallet before

improvement

After improvement




Principle 5: Reduce Excessive

Motions

• simplest ways to reduce manual

repetitions is to use power tools



• Change layout of equipment toeliminate motions

Sliding the product in

P5: Reduce Excessive Motions



• uneven surfaces or lips that are in

the way

P5: Reduce Excessive Motions



Principle 6 : Minimize

Fatigue and Static Load

• Holding the load at sameposition for a long period of time is known as static load.

•It creates fatigue anddiscomfort and can interferewith work.



• Example: having

to hold parts and

tools continually.Using a fixture

eliminates the

need to hold onto

the part.

P6 : Minimize Fatigue and

Static Load

P6 Mi i i F ti d



P6 : Minimize Fatigue and

Static Load



• hold your arms overhead for a fewminutes will affect the shoulder

muscles.

• Sometimes orientation of the work

area can be change to prevent this,

or sometimes extenders are added

to the tools.

P6 : Minimize Fatigue and Static Load



• Having to stand for a long time creates

a static load on

your legs.

• Having a footrest

can permit you to

reposition your legsand make it easier

to stand.



Another thing to watch out

for is excessive pressure

points, sometimes called"contact stress."

Principle 7

Minimize Pressure Points



P7 : Minimize Pressure Points

A good examples of

this is squeezing hard

onto a tool:

A pair of pliers –

adding a cushioned

grip and contouring

the handles to fit your

hand




Leaning forearms

against the hard edge

of a work table

creates a pressurepoints.

Rounding out the

edge and padding it

usually helps




Seated position:

- behind knees when chair istoo high or when your dangleyour legs.

- between your thigh and

bottom of the table Standing position:

- a slightly more subtle kind of pressure points occurs whenstanding on a hard surface,like concrete.

- heels and feet begin to hurtand whole legs can begin to

tire.



Principle 8Provide Clearance

Having enough clearance is a

concept that is easy to relate to.



P8: Provide Clearance

Work Areas:

- Work spaces must have

adequate clearance for the

user’s head, arms, knees,

feet and body

- Eliminating barriers and

obstruction between the

worker and the items needed

in the task

- The largest individuals who

will use the work space

determine the amount of

clearance needed



P8: Provide Clearance

Being able to see:

- Equipment should

be built and tasksshould be set up so

nothing blocks your

view



Principle 9

Move, Exercise, and Stretch

To be healthy the human body

needs to be exercised and

stretched.



Depending upon the type of work you do,

different exercises on the job can be helpful.

Physically demanding job:

- stretch and warm up beforeany strenuous activity

Sedentary job:

- take a quick ‘energy break’every so often to do a fewstretches.

Sit for long periods:

- Adjust the seat up and downthroughout the day

- Move, stretch and changeposition often



Principle 10

Maintain a Comfortable

Environment

A good environment will aid peoplein achieving their objectives whilstretaining effort, stress and errors

within tolerable limits

P10 M i t i C f t bl



P10: Maintain a Comfortable

Environment

Lighting and glare:- Lighting can have a

considerable effect onboth comfort and

performance.- Excessive bright

fluorescent and too littlelighting can cause eyestrain, especially when it

creates glare

P10 Maintain a Comfortable




Environment

How to solve lighting

problems:

- By using task lighting:

having a small light

right at your work that

you can orient andadjust to fit your

needs



P10 M i t i C f t bl



Vibration- Vibrating tools can be

damped

- Excessive levels and

durations of exposure

to whole-body vibrations

-- back pain and

performance problems.


Environment

- Proper selection and

usage of hand tools

-- reduce the likelihood of

developing work-relatedMSDs in the hands, wrists

and arms.



Noise- Is annoying sound that can

inversely affect safety and

performance

- Affect psychologicalresponses

- Long run noise may result

health impairment and

contribute to stress at the

workplace- Prolonged exposure can

cause temporary or

permanent hearing loss


Environment




Environment

Thermal

- Heat and cold can cause illnesses and

injuries in the exposed individuals.

- Thermal changes can cause accidents

(fire and explosion) and injury to people.

- Heat & cold stress – major hazards

reduces productivity



Principle 11

Make Displays and ControlsUnderstandable

A proper design of the human-machine interface is of greatimportance for enhancing the

operator’s productivity, safety, and well-being.

P11 M k Di l d C t l



P11: Make Displays and Controls

Understandable

Displays and controls areusually interrelated

they should be:

- Designed to be

compatible

Properly group together sothat the relationship between

each pair of displays and

controls can be easily

understood by the operator



Principle 12Improve Work Organization

Awareness and participation of bothemployees and the management aretwo critical factors required for solving

occupational problems.

P12 I W k O i ti



Job rotation

- A well designed rotation scheme can be especiallyhelpful in reducing the risk of injury when working

overtime at repetitive tasks.

Job enlargement

- Add meaningful variety to employees’ jobs, reducingtheir risk of injury while potentially improving their

morale.

- Combined tasks to make the work more interesting

and varied- Combined VDT work with other tasks to increase

productivity and other tasks to increase productivity

and reduce fatigue

P12: Improve Work Organization




General understanding of ergonomics

principles and having good equipment

available helps solve many problems.

Job design factors such as scheduling,

job rotation, motivation and consultation

can improve work organization by

involving the management and the

workers.

P12 I W k O i ti



Staffing and scheduling- Adjust scheduling to spread out highly repetitive task

over a longer time, rather than letting a job wait until itrequires lengthy repetitive work.

Rest breaks

- Breaks at mid-morning, lunch and mid-afternoon isan important part of allowing employees time torecover from the demands, both mental and physical,

of their jobs.


P12 I W k O i ti



Encouraging workers

involvement- Involved them in planning

process

- Solve work problems byinvolving workers in group.

- Involve workers in planningday-to-day work

Consultation

- On improving working-time

arrangements- When there are changes in

production or improvement areneeded


P12 I W k O i ti



Motivation- Rewards workers for their

participation in improving

productivity and the

workplace.- Inform workers frequently

about the results of their

work.

- Provide opportunities for workers to learn new skill.




CONCLUSION

• Ergonomics is a science which, when appliedeffectively, can lead to marked improvementsin working conditions.

• Improvements can be made by properlydesigning or redesigning the way jobs areperformed, the content of job tasks, themethods in which equipment is handled or setup, the way work schedules are set, theequipment used to perform a job and etc.



CONCLUSION

• Positive changes in these areas or others canhelp to prevent injuries and illnesses

-- physical or psychological – caused by a

lack of attention to ergonomic principles in theworkplace.

• Implementing ergonomic improvements does

not have to be complicated or difficult. Theunion, workers and management should worktogether to assess priority problem areas anddevelops solutions.



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12 Ergonomics Principle

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