THEME 1 – INTRODUCTION TO
ERGONOMICS & HUMAN FACTORS
Ergonomics: an applied scientific discipline that is concerned with how humans interact with the tools &
equipment they use while performing tasks & other activities
International Ergonomics Society (IEA) definition: scientific discipline concerned with the understanding of
the interactions among humans & other elements of a system & the profession that applies theory, principles,
data, and methods to design in order to optimise human well-being and overall system performance
Greek words ergon (work) & nomos (rules/laws)
Our primary interest is on the activities humans perform while working
• These impose a continuum of physical & cognitive demands on the human worker
• Most human activities require a combination of physical & cognitive exertions
PURE PHYSICAL PURE COGNITIVE
Requirements: muscle
strength & endurance, most work activities require a combo Requirements: intelligence,
physical conditioning concentration, knowledge
Ergonomics is also concerned with the physical & social environment in which the tasks & activities are
performed & how humans and machines interact with the environment
Terms “ergonomics” & “human factors” are synonymous à only difference is:
• Ergonomics emphasised work physiology & anthropometry
• Human factors emphasised experimental psychology & systems engineering
What we can learn from the definitions:
• Primary purpose of HFE is design
• In HFE, a systematic, interdisciplinary approach is necessary for design & analysis systems & products
,HISTORY OF ERGONOMICS
1850 Industrial revolution (& mechanisation)
1875 “Scientific management”
• “Taylorism”
• Emphasis on task planning, motion & time study, & worker efficiency
• Critics argue it created industrial jobs that were simplistic & repetitive &
dehumanised labour
• On other hand, made possible most productive industrial system in world (in US)
• Pioneering studies of Frank & Lillian Gilbreth in the area of motion study – one of
the forerunners of human factors
1900 Industrial psychology, work study, WW1
• FMJ
1923 Hawthorne Studies (Human Relations)
• Drew attention to the importance of social factors in the workplace
• Represented the beginning of interest in “human relations” research
1940 WW2 (complex equipment, training, accidents) “Knobs & Dials”
• Forced nations to develop modern production technologies
• Increase in technological complexity & sophistication of weapons systems
• Loss of life often the result of operation of this equipment
• Knobs and dials à interest in aircraft & other weapons systems
1949 Ergonomics
• K.F.H Murrell gave the discipline its name
1950 Ergonomics Research Society adopted à name later changed to Ergonomics Society
1965 Human Rights (work, health, quality of life, subgroups, laws, standards)
1975 Computers, information technology, automation
1990 Environmental quality, diversity, global village, work changes (right to work, work ethics),
decrease costs by layoffs (downsizing), technology
2000+ Rapid & radical technology changes (more automated complex systems)
Since 1970, the following significant human-related disasters have contributed to public awareness about
importance of HFE:
• Three Mile Island nuclear power plant accident (Harrisburg, Pennsylvania, March 1979)
• Bhopal pesticide plant, Union Carbide Company (Bhopal, India, December 1984)
• Challenger space shuttle (above Cape Kennedy, Florida, January 1986)
• Chernobyl nuclear power plant explosion (Kiev, Ukraine, April 1986)
• Exxon Valdez oil spill (Prince William Sound, Alaska, March 1989)
• Columbia space shuttle (over Texas, February 2003)
Many of these were result of human errors & sometimes caused by inadequate attention to HFE in system
design & system management, & other times caused by flaws in decisions by humans
OVERVIEW OF ERGONOMICS
OBJECTIVES & APPLICATIONS OF ERGONOMICS
Main objective of ergonomics is to improve the performance of systems consisting of people & equipment
(often referred to as human-machine systems)
Better performance of human-machine systems means:
• Greater ease of interaction between the user & equipment
, • Avoidance of errors & mistakes by the user
• Greater comfort & satisfaction in the use of equipment
• Reduced stress & fatigue while using the equipment
• Greater efficiency & productivity
• Safer operation of the equipment
• Avoidance of accidents & injuries
3 fundamental goals à safety, productivity, satisfaction
Objectives are similar to those in methods engineering
• To improve performance of existing systems
• To design new systems for optimum performance
Ergonomics has a wide variety of applications, nearly all of which can be classified into 2 main areas:
• Work system design à this area is concerned with the interaction between worker & the equipment
used in the workplace. Objectives include safety, accident avoidance, and related performance
attributes. Includes consideration of factors related to the work environment such as lighting & noise
levels
• Product design à this area deals with the design of products that are safer, more comfortable, and
more user-friendly & mistake-proof. In addition to providing greater customer satisfaction by means
of these kinds of features, an issue in product design is product liability lawsuits & their avoidance
through consideration of ergonomics
We focus on work systems, which in fact overlap with product design à work systems usually include
equipment, & equipment is designed & fabricated by companies that are selling it as a product
A production machine is a product that must be designed with ergonomics in mind if it is to operate
productively & safely
FITTING THE JOB TO THE PERSON (FJP)
A philosophy (“Fitting the man to the job” FMJ) which recommended that workers be selected on the basis of
their mental aptitudes & physical characteristics for a particular job opening
Psychometric testing had begun to be used following WWI in the hiring process in order to improve
productivity by trying to identify workers who had the right psychometric capabilities à physical attributes
also used in selection process for jobs requiring characteristics such as size & strength
The FPJ (fitting the person to the job) approach is still considered among the eligibility factors for certain
positions in many hiring situations today à firefighters (endurance), military pilots(height),
doctors/lawyers(education)
Ergonomics approach is diametrically opposite of FPJ à “fitting the job to the person” (FJP)
• Designing the job so that nearly any member of the workforce can perform it
• WHY FJP has evolved and now occupies a position that operates in parallel & sometimes supersedes
the FPJ approach:
o Changes in worker skill requirements
o Demographic changes
o Social & political changes
, • Changes in worker skill requirements à general skill requirements for many jobs in early 1900s were
much lower than today & there were many applicants (incl. young people) à companies could be
more selective when hiring workers
o Skill requirements are much higher today à operation of machinery & computers as
opposed to physical/clerical work before
o Average age of available workforce is now older
o Companies are often faced with a smaller pool of applicants & cannot afford to be choosy à
must hire from pool, those who are qualified but not necessarily optimal in the FPJ sense
o Training must be provided & work itself must be designed to be readily understood so that
necessary training can be minimised & workers can be productive ASAP after employment
begins
• Demographic changes à more women have entered the workforce in positions heretofore
dominated by male workers
• Social & political changes à effecting changes in cultural attitudes & government regulations
o Equal opportunities legislation was enacted to prevent discrimination on the basis of race,
gender, age
o Laws were enacted at the state & federal levels to mandate that physically handicapped
persons be provided with access ramps & other conveniences at public facilities & in
transportation à hiring of the handicapped was encouraged
o In some cases, organisations went beyond legislation by pursuing proactive policies on the
hiring of minorities & the handicapped
HUMAN-MACHINE SYSTEMS
Human-machine system: a combination of humans & equipment interacting to achieve some desired result
• Number of humans & type of equipment can range, desired result achieved by the system refers to its
purpose and/or function
• Can have multiple objectives
3 basic categories of human-machine systems:
1. Manual systems à involves a person using some hand tool or non-powered implement to perform
an activity à a farmer using a pitchfork to load hay into a wagon or man using spade to dig a hole
2. Mechanical systems à one or more humans using powered equipment to accomplish some job à
equipment provides mechanical power for the job & human(s) control the equipment à farmer
driving a tractor to harvest a crop
3. Automated systems à involves the performance of a job with a minimum of human attention à do
require occasional human attention (maintenance, repair, reprogramming, loading/unloading of
parts) from a production & humans are required to design & install it