WORKPLACE
ENVIROMENT AND
ERGONOMICS
ERGONOMICS
WHAT IS ERGONOMICS??? Ergonomics is the study of fitting the
work/job to the individual. Ergonomics matches the design of tools, controls, and equipment to fit the safety needs of the operator. Since each of us has different needs, ergonomic design of tools, equipment, and workspaces must be adjustable enough to accommodate a varied range of body types.
INTRODUCTION Derived from two Greek works: “Nomoi” meaning natural laws “Ergon” meaning work Ergonomics addresses the relationship
between people , their tasks , equipment and work environment
Hence , ergonomists study human capabilities in relationship to work demands…
HISTORY OF ERGONOMICS In 1857,Wojciech Jastrzebowski created
the word “ergonomics” in a narrative he wrote about the science of nature.
World war ll in 1943, an army officer Alphonse Chapanis, learned that if the control layout in the cock pits of plane were simplified, the pilot make fewer errors.
HISTORY OF ERGONOMICS (CONT’D) After world war ll, ergonomics not only
productivity, but also the safety of the workers.
Research take place in various area The affect of heavy labor on the heart;
the maximum loads that should be pulled , pushed or carried
The amount of muscle force that should be required to perform
WORKSTATION DESIGN
PRINCIPLE
GENERAL ERGONOMICS PRINCIPLE FOR WORKSTATION DESIGN Work surface Sit or stand? Fitting all the pieces
together Accepted postured Sitting basics Work surface basics Keyboard / mouse
basic
Alternative input devices
Monitor basic Telephone basic Source documents Additional
accessories Work/rest schedule
WORK SURFACEHEIGHT May very depending on task ; e.g surface
higher for writing and typing Should not contact the thighs or kneesWidth Wide enough to accommodate all needed
input devices, task materials and accessories Enough clearance for legs and any items
stored below work surface
WORK SURFACE…CONT’DDepth Allow for allow positioning of monitor Allow for postural changes Knees should not contact items /
support structure under work surface
SIT OR STAND?Sit when Doing fine manipulated Need high visual attention Need high degree of stability Precise foot control is needed There is not heavy material handling Task requires fixed postured for
extended periods
SIT OR STAND?....CONT’D Frequently handle heavy objects or
when experience heavy downward forces
Mobility is required Frequently need to make extended
reaches Doing a variety of tasks Doing work intermittent work Have low back pain
FITTING ALL THE PIECES TOGETHER Seating Work surface Keyboard Monitor Telephone Additional accessories Work/ rest schedule Manual material handling
ACCEPTED POSTURESUpright ThighsReclinedStandingMove throughout these postures
SITTING BACISHips slightly higher than kneesFeet supported Lumber support below beltlineBack angle upright or slightly reclinedArms relaxed or supported
WORK SURFACE BASIC Design must be based on job tasks Surfaces should be height adjustable Reading/ writing surface 2 inches higher
than elbow height Keyboard / mouse surface elbow height
KEYBOARD / MOUSE BASICS At or slightly lower than elbow height Neutral wrist postures Relax shoulders Use a light touch
ALTERNATIVE INPUT DEVICES Split keyboard design Vertical or concave keyboard design Trackball Touchpad Mouse with a supinated angle Always use on a trial basis prior to
purchase
MONITOR BASICS25 – 36 inches from eyesAt or slightly lower than eye levelDirect alignment Avoid glare or contrast from bright light sources
ADDITIONAL MONITOR BASICS Ambient light levels 20-50 foot candles Refresh rate 70-80 Hz Dark characters on a light background Clean monitor at least 1x per week
TELEPHONE BASICS Avoid cradling the hand set between
your shoulder and head Hold the hand set with your dominate
hand Use a headset or speaker phone when
appropriate
SOURCES DOCUMENTS Document holder -adjacent to monitor -between monitor and monitor Reading / writing slope
ADDITONAL ACCESSORIES Large grip pen/pencil -decrease stress on muscles/tendons Wrist rest -Use only while pausing between key
strokes Footrest -essential when feet do not touch the
floor -help promote postural changes
WORK/REST SCHEDULE Rotate job tasks at least 1x per hour Utilize schedule breaks Incorporate stretching into daily routine Change postures frequently Get out of your chair
WORK/REST SCHEDULE Rotate job tasks at least 1x per hour Utilize schedule breaks Incorporate stretching into daily routine Change postures frequently Get out of your chair
ERGONOMICS RISK Forceful exertions Repetitive motions Awkward postures Static postures Compression or contact stress Lighting Vibration Noise Cold temperatures
FORCEFUL EXERTIONS Forceful muscular exertions place high
loads on the muscles, tendons, joints, and discs, and so are associated with most musculoskeletal disorders.
Increased muscular exertion results in the increase of muscles fatigue.
With increased muscle fatigue, time needed to recover increases. If recovery time is limited, soft tissue injury is more likely to occur.
REPETITIVE MOTIONS Repetitive Motion Injuries (RMI, also
known as RSI, CTD, CTS) are a class of injuries and illnesses that result from weeks, months, or years of overuse of human joints.
Connective tissues can become sore and sometimes unusable from repeated exposure to micro-trauma.
Because of the slow onset of symptoms, people sometimes ignore the condition until the symptoms become chronic and permanent injury occurs.
AWKWARD POSTURES Awkward postures refer to positions of
the body (limbs, joints, back) that deviate significantly from the neutral position while job tasks are being performed.
For example, when a person's arm is hanging straight down (perpendicular to the ground) with the elbow close to the body, the shoulder is said to be in a neutral position.
AWKWARD POSTURES (CONT’D) When employees are performing
overhead work such as installing or repairing equipment or grasping objects from a high shelf, their shoulders are far from the neutral position.
STATIC POSTURES "Static work" refers to the
musculoskeletal effort required to hold a certain position, even a comfortable one.
For example, when we sit and work at computers, keeping our head and torso upright requires either small or great amounts of static effort depending upon the body positions we choose.
CONTACT STRESS Contact stress results from occasional,
repeated, or continuous contact between sensitive body tissue and a hard or sharp object.
Contact stress commonly affects the soft tissue on the fingers, palms, forearms, thighs, shins and feet.
LIGHTING Lighting that is not appropriate for work
task is a major factor in visual discomforts such as eyestrain, burning or itchy eyes, headaches and blurred or double vision.
VIBRATION Vibration restricts the blood supply to
the hands and fingers, which, depending on the vibration level and duration of exposure, can contribute to an ergonomic injury.
Signs and symptoms of vibration-induced injury, such as Reynaud's phenomenon, start with occasional numbness or loss of colour in the fingertips.
NOISE Noise is an often overlooked part of the
working environment. Office machines, phones, and
coworkers' conversations can be a distraction.
COLD TEMPERATURES Cold temperatures reduce the natural
elasticity of the body and reduce the sensation of touch (tactile feedback).
In order to get the same amount of tactile feedback, an employee may exert more force than is necessary.
WORKPLACE ENVIRONMENT
5S
WHAT IS 5S?? There are 5 primary phases of 5S:
sorting, straightening, systematic cleaning, standardizing, and sustaining. Additionally, there are three other phases sometimes included; safety, security, and satisfaction.
SORTING (SEIRI) Eliminate all unnecessary tools, parts,
and instructions. Go through all tools, materials, and so
forth in the plant and work area.
STABILIZING OR STRAIGHTENING OUT (SEITON)
The place for each item should be clearly labeled or demarcated.
Items should be arranged in a manner that promotes efficient work flow, with equipment used most often being the most easily accessible.
SWEEPING OR SHINING (SEISO) Clean the workspace and all equipment,
and keep it clean, tidy and organized. At the end of each shift, clean the work
area and be sure everything is restored to its place.
STANDARDIZING (SEIKETSU) All work stations for a particular job
should be identical. All employees doing the same job
should be able to work in any station with the same tools that are in the same location in every station.
SUSTAINING THE PRACTICE (SHITSUKE)
Maintain focus on this new way and do not allow a gradual decline back to the old ways.
While thinking about the new way, also be thinking about yet better ways.
APPERECIATE THE PROPER AND SAFE
METHOD OF ERGONOMICS IN THE
WORKPLACE
SAFE METHOD
THANK YOU