ERGONOMICS IN OCCUPATIONAL THERAPY
What is Ergonomics?
The study of work performance → emphasis on keeping workers safe and productive
o Originated in work
o Also applicable to other areas of OT (play, leisure, learning, PCL, social
interaction)
o Aka human factors
Multidisciplinary field of study
o Developed from interests of engineers, psychologists, & health professionals
There are now degrees in Ergonomics / human factors up to doctoral level
But many professionals still use ergonomics in their practice, including OTs
What is the purpose of Ergonomics?
Optimization of relationship between environment and person
When there are no ergonomic problems, user is unaware of design issues and can
focus on task
What is the role of OT in Ergonomics?
Three main areas of practice:
o Workplace analysis for prevention of work-related musculoskeletal injuries
o Tool and workplace design for persons with disabilities (including universal
design)
o Development of ergonomics training programs through consultation and
participation
How does client-centered practice relate to ergonomics?
Inclusion of persons with disabilities in design and decision making
o Advocating for client needs
o Recognising clients’ knowledge and experience
Important to collaborate with the individuals involved when applying ergonomics in
institutions
What are the principles of client-centered practice relating to ergonomics?
o Enacting participation and partnering throughout the process
o Respecting and enabling worker and organization choices, needs, and
knowledge
o Focusing on Person-Environment-Occupation (PEO) relationships in practice
context
o Addressing physical comfort and emotional support needs of clients
o Fostering open and transparent communications and knowledge exchange
o Establishing a shared vision for ergonomic management
o Establishing shared and realistic goals among work parties
o Creating opportunities and engage workplace parties in problem solving and
decision making
o Ensuring a flexible and individualized occupational therapy approach
,What is Anthropometry?
Science of measurement of human body
What are the universal factors that affect human size & shape?
o Gender
o Ethnicity
o Age
o Occupation
Disability is often overlooked in environmental and product design
What is the application of anthropometry?
What is Reach?
o a sphere around worker that can be touched at all points without moving the
body from the starting point
If standing with arms unobstructed:
Shoulder will be the axis / centre of sphere
Length of arm is the radius
If arms are obstructed (i.e., working at desk)
Elbow is the axis / centre of sphere
Forearm to hand distance is the radius
o What is Vertical Reach?
area that person can reach from top to bottom
represented by an arc
Determine:
Posture at rest: sitting/standing; elbow & shoulder
flexed/extended?
Occasional extended reach is the extra area person can reach when
leaning forward
E.g., Working on vertical control panels,
reaching objects off high shelves
o What is Horizontal Reach?
area person can reach from front to back
defined by the counter, desk, or tabletop
Four zones:
Normal work distance:
→ arc made by forearm when the body is close to the table
and elbow close to the body.
→ Most precision work is done in this area.
Extended working distance:
→ Area made by the arc of the arm when the elbow is straight.
→ Frequently used tools, supplies and heavy objects should
be stored in this area.
Maximum work distance:
→ arc made when the trunk leans forward
→ Infrequently used tools and supplies should be stored here.
Most efficient workspace:
→ 250mm square directly in front of the worker, about a hand’s
span from the edge of the table
→ Most people prefer to work in this zone.
o What is Visual Reach?
, area worker can comfortably see from static position
Most relaxed area is 10 to 15 degrees below horizontal
Place screens and monitors
Eye can comfortably see 15 degrees above and
below this angle
Comfortable reading distance is 400mm to 700mm
from the eye
What is Clearance?
o Leg room
o Seated work should allow space for legs to move and change position
o Drawers under work surfaces and thick counters reduce leg room
What are the principles of Ergonomic Posture?
o Both Standing and sitting have advantages
The best position is as close to neutral as possible – least strain on
the body
Standing:
o head aligned upright over trunk
o centre of gravity over hips
o knees slightly bent
o arms in a relaxed position
Sitting:
o Leaning back slightly in the chair at 105 degrees
(slightly reclined)
o knees and ankles at 90 degrees.
Static postures can lead to development of musculoskeletal disorders.
→ Postures should be changed frequently
Forward flexion of the neck should be avoided. Rather lift the work
surface.
Upper arms should be close to the body, and lifting arms overhead
should be avoided.
Body parts should be in neutral position as far as possible – avoid
twisting and asymmetry.
Avoid extreme ranges of motion and awkward postures.
Back support should always be provided.
Place body parts in positions of greatest strength
What is Precision and Stength?
o Precision work (e.g., electronics, jewellery, sewing)
closer to the eyes
close to the body
arms or hands should be supported while working
should be done at 50mm to 100mm above elbow height
o Light work (e.g., typing, writing)
done at just below elbow height
o Work requiring strength (e.g., kneading dough, hammering)
150 to 400mm lower than elbow height
What is Ergonomics?
The study of work performance → emphasis on keeping workers safe and productive
o Originated in work
o Also applicable to other areas of OT (play, leisure, learning, PCL, social
interaction)
o Aka human factors
Multidisciplinary field of study
o Developed from interests of engineers, psychologists, & health professionals
There are now degrees in Ergonomics / human factors up to doctoral level
But many professionals still use ergonomics in their practice, including OTs
What is the purpose of Ergonomics?
Optimization of relationship between environment and person
When there are no ergonomic problems, user is unaware of design issues and can
focus on task
What is the role of OT in Ergonomics?
Three main areas of practice:
o Workplace analysis for prevention of work-related musculoskeletal injuries
o Tool and workplace design for persons with disabilities (including universal
design)
o Development of ergonomics training programs through consultation and
participation
How does client-centered practice relate to ergonomics?
Inclusion of persons with disabilities in design and decision making
o Advocating for client needs
o Recognising clients’ knowledge and experience
Important to collaborate with the individuals involved when applying ergonomics in
institutions
What are the principles of client-centered practice relating to ergonomics?
o Enacting participation and partnering throughout the process
o Respecting and enabling worker and organization choices, needs, and
knowledge
o Focusing on Person-Environment-Occupation (PEO) relationships in practice
context
o Addressing physical comfort and emotional support needs of clients
o Fostering open and transparent communications and knowledge exchange
o Establishing a shared vision for ergonomic management
o Establishing shared and realistic goals among work parties
o Creating opportunities and engage workplace parties in problem solving and
decision making
o Ensuring a flexible and individualized occupational therapy approach
,What is Anthropometry?
Science of measurement of human body
What are the universal factors that affect human size & shape?
o Gender
o Ethnicity
o Age
o Occupation
Disability is often overlooked in environmental and product design
What is the application of anthropometry?
What is Reach?
o a sphere around worker that can be touched at all points without moving the
body from the starting point
If standing with arms unobstructed:
Shoulder will be the axis / centre of sphere
Length of arm is the radius
If arms are obstructed (i.e., working at desk)
Elbow is the axis / centre of sphere
Forearm to hand distance is the radius
o What is Vertical Reach?
area that person can reach from top to bottom
represented by an arc
Determine:
Posture at rest: sitting/standing; elbow & shoulder
flexed/extended?
Occasional extended reach is the extra area person can reach when
leaning forward
E.g., Working on vertical control panels,
reaching objects off high shelves
o What is Horizontal Reach?
area person can reach from front to back
defined by the counter, desk, or tabletop
Four zones:
Normal work distance:
→ arc made by forearm when the body is close to the table
and elbow close to the body.
→ Most precision work is done in this area.
Extended working distance:
→ Area made by the arc of the arm when the elbow is straight.
→ Frequently used tools, supplies and heavy objects should
be stored in this area.
Maximum work distance:
→ arc made when the trunk leans forward
→ Infrequently used tools and supplies should be stored here.
Most efficient workspace:
→ 250mm square directly in front of the worker, about a hand’s
span from the edge of the table
→ Most people prefer to work in this zone.
o What is Visual Reach?
, area worker can comfortably see from static position
Most relaxed area is 10 to 15 degrees below horizontal
Place screens and monitors
Eye can comfortably see 15 degrees above and
below this angle
Comfortable reading distance is 400mm to 700mm
from the eye
What is Clearance?
o Leg room
o Seated work should allow space for legs to move and change position
o Drawers under work surfaces and thick counters reduce leg room
What are the principles of Ergonomic Posture?
o Both Standing and sitting have advantages
The best position is as close to neutral as possible – least strain on
the body
Standing:
o head aligned upright over trunk
o centre of gravity over hips
o knees slightly bent
o arms in a relaxed position
Sitting:
o Leaning back slightly in the chair at 105 degrees
(slightly reclined)
o knees and ankles at 90 degrees.
Static postures can lead to development of musculoskeletal disorders.
→ Postures should be changed frequently
Forward flexion of the neck should be avoided. Rather lift the work
surface.
Upper arms should be close to the body, and lifting arms overhead
should be avoided.
Body parts should be in neutral position as far as possible – avoid
twisting and asymmetry.
Avoid extreme ranges of motion and awkward postures.
Back support should always be provided.
Place body parts in positions of greatest strength
What is Precision and Stength?
o Precision work (e.g., electronics, jewellery, sewing)
closer to the eyes
close to the body
arms or hands should be supported while working
should be done at 50mm to 100mm above elbow height
o Light work (e.g., typing, writing)
done at just below elbow height
o Work requiring strength (e.g., kneading dough, hammering)
150 to 400mm lower than elbow height
