History of ergonomics
Ergonomics is the scientific study of human work and the work is
derived from the Greek ergon, work and nomos natural law
Bernadino Ramazzini originally highlighted the ergonomic problem
with musculoskeletal problems being described by clerks in the early
1700’s (de Morbis Artificum Diatriba (Diseases of Workers))
The word was coined as a result of a working party in 1949 requiring a
name for their research into the efficiency of the fighting man
In the United States, the term Human Factors is often used
Ergonomic principles
Ergonomics is the science of matching the job to the worker and the
product to the user
An effective match is one which optimises:
– Working efficiency (performance, productivity etc)
– Health and safety
– Comfort and ease of use
Problems with the working environment
• Standing
• Sitting
• Reaching
• Noise
• Unsuitable lighting
• Strenuous work
• Repetition
• High impact force on the upper
limbs
• Fatigue
• Changing shift patterns
• Thermal comfort
• PPE
• Different size operators
• Poorly designed alarms
• Unsuitable equipment
• Boredom
• Stress / anxiety
• Lack of training
• Poorly designed visual displays
• Backache / arm pain / headache /
other medical symptoms
Standing
• Humans are designed to stand on two legs but are not designed to
stand still
• Standing for long periods can lead to discomfort due to loads being
placed on the body
• People rarely stand still for any length of time – if not walking they
adopt a variety of resting positions
• In industry, standing work may prohibit the opportunity to practise
these behaviours due to design of the workplace
• Short periods of walking is vital to activate the venous pump and
therefore assist the return of blood from the lower limbs
The venous pump
The Venous Pump - which is
often called the "muscle pump"
or "peripheral heart" - depends
on:
1 Movement - of the leg and
particularly the ankle
2 Valves - situated in the veins
Standing still for long periods
may result in insufficient blood
return and fainting may occur
Characteristics of unconstrained standing
• Never stand still
• Bear weight on one leg
• Lean backwards against anything
• Lean sideways against vertical
surface
• Rest hand on head
• Rest pelvis against counter
• Maximise contact with fixed objects
• Rest one foot on an object
• Hang on elbows
• Sit on heels against a wall
• Use a footrest
• Sit down when tired
• Hang on to overhead objects
• Rest knee on something
• Lean over and rest hands on knees
• Use arms as a prop on work
surfaces
Static work V dynamic work
Static
Poor exchange of blood
Build up of waste
Causes discomfort
May damage the muscle
Dynamic
Good exchange of blood
Exchange of nutrients and waste
Less likely to damage muscle
Anthropometry
This is the branch of the human sciences that deals with body
measurement and in particular:
• Body size
• Shape
• Strength
• Working capacity
Choose a car … any car
Correct choice?
Peugeot 207 convertible seat pan height 520 mm
Audi A3 convertible seat pan height 480 mm
Honda seat pan height 680 mm
Average Hip height for adults aged 45 – 65
male 910 mm female 805mm
Driver posture Guide
The Highways Agency suggest the following steps to set up a good
driving position:
• Raise the seat as high as is comfortable to improve your vision of
the road
• Move the seat forward until you can easily fully depress the clutch
and accelerator pedals
• Adjust cushion tilt angle so that the thighs are supported along the
length of the cushion
Driver posture Guide - cont
• Adjust the backrest so that it provides continuous support along the
length of the back and is in contact up to shoulder height
• Adjust the lumbar support to give even pressure along the length of
the backrest
• Adjust the steering wheel rearwards and downwards for easy reach
• Adjust the head restraint to ensure the risk of injury is reduced in the
event of a car accident
• Adjust the rear view and side mirrors ensuring that they can be used
without excessive straining of the neck or upper body
Repetitive Driving Injury (RDI)
• Study undertaken by eBay motors revealed that almost half of British
drivers (48%) are suffering from musculoskeletal pains due to poor
driving posture
• The 5 most common complaints are:
Foot cramp
Lumbar pain
Stiff neck
Side ache
Headache / eyestrain
Are you a rollercoaster or a pimp?
The rollercoaster (37% of population)
Driver leaning forward, sat upright,
seat forward
Common symptoms:
• Shoulder pain, neck strain, leg
cramp and side ache
Remedy
• Relax – tense, nervous drivers more
likely to adopt this posture. Take
regular breaks and stretch the legs
The multi tasker (26% of population)
Driver has straight back, arms bent,
one hand on gearstick. Almost half of
mobile office workers are multi-taskers
Common symptoms:
• Headaches, eyestrain, feet cramp and
coccyx pain
Remedy
• Adjust seat regularly, consider
automatic vehicle
The racer (19% of population)
Driver has straight arms, seat reclined,
straight legs and low driving position
Common symptoms:
Side ache and lumbar pain
Remedy
Be aware that low seat positions (and
bucket seats) provide limited back
support. Knees should not be higher
than your hips
The pimp (8% of the population)
• Seat reclined, arm on window ledge,
one hand on wheel. Typically male
drivers aged 25 – 35
Common symptoms:
• Arm and shoulder ache from resting on
the ledge (probably a bit of NIHL from
Dizzee Rascal being played too loud!)
Remedy
Sit upright with knees lower than the
hips. Keep both hands on the wheel
Proper driving footwear properties
The sole of the shoe should be no more than 10 cm, be too thin or soft
There should be enough grip to prevent the sole from slipping off the pedals
The shoe should not be too heavy or limit ankle movement
It should not be wide enough not to accidentally step on two pedals
Avoid
The car as an office
• Avoid using a laptop positioned on the passenger seat – this results in
severe twisting of the spine
• Store your laptop in the boot – at least you will change position and
get the opportunity to stretch your legs before work
• Try to find a suitable stop i.e service area so that the laptop can be
used on the table
• Avoid working with paperwork leaning ion the steering wheel
• Regular change of position is a must – take a break at lkeast every 15
minutes
• Ensure that you get out of the car and stretch your legs once you
have finished working and efore you set off on your journey
Manual handling from a vehicle
• Park as close to the destination as possible
• Reverse in to gain extra space
• Clear all obstacles in your path
• Open doors if required
• Only carry what you can manage – use wheeled devices
• Do not overload – make several journeys
Musculoskeletal disorders
Bernadini Ramazzini, the father of Occupational Medicine wrote in his
De Morbis Artificum of 1713, when referring to disease that affect
scribes and notaries:
‘the maladies that afflict the clerks aforesaid arise from the three
causes: first, constantly sitting, secondly the incessant movement of
the hand and always in the same direction, thirdly the strain on the
mind from the effort not to disfigure the books by error or top cause
loss to their employers when they add, subtract, or do other sums in
arithmetic’
Also known as ……
UK Work Related Upper Limb Disorder (WRULD)
Upper Limb Disorder (ULD)
Australia Repetitive Strain Injury (RSI)
Occupational Overuse Syndrome (OOS)
New Zealand Occupational Overuse Syndrome (OOS)
USA Cumulative Trauma Disorder (CTD)
Canada Repetitive Strain Injury (RSI)
Scandinavia Occupational Cevicobrachial Disorder (OCD)
Japan Occupational Cevicobrachial Disorder (OCD)
World-wide Work Related Musculoskeletal Disorder (WMSD)
Carpal Tunnel Syndrome
• Pressure on the median nerve as it
passes through the wrist
• Also known as nocturnal numbness
as the tingling can wake the
individual from sleep
• May be caused by repetitive type
work with a bent wrist or vibrating
hand tools
Lateral and medial epicondylitis
• More commonly referred to as
tennis and golfer’s elbow
• Inflammation of the area where
tendon and bone join. Lateral on
the outside, medial on the inner
• May be caused by repetitive,
forceful work