These lecture notes were not written as a course handout, but as a resource for lectures. Therefore, references and comments will not always be complete.
(part 3 of 5)
Notably there are a number of areas of knowledge that focus on
people in the work place. These areas cannot be subsumed under
one title because they reflect many different approaches that are
often theoretically inconsistent and even
contradictory.
HF itself is not a consistent coherent body of knowledge but a
pragmatic amalgam without clear boundaries of potentially useful
approaches to and data about practical problems. This means there is
no single definition, or description of Human Factors practice.
Rather, different activities which may be described as falling within
the remit of Human Factors may be philosophically and politically
incompatible and what is considered to be HF work depends on the
climate where that work takes place.
Related activities include scientific management, industrial,
occupational and social psychology, human relations, organisational
behaviour, work psychology and of course human factors. In addition,
as many of you will know, HF is closely associated with ergonomics.
Given this broad view of Human Factors, it is not surprising that HF
involves multidisciplinary research, including input from
engineering, cognitive psychology, organisational/occupational
psychology, anthropology, sociology, social psychology, linguistics,
and mathematics. It is concerned with legal, psychological,
organisational and occupational considerations.
Before the second world war "industrial" psychology was the commonest
term for studies of work environments, people and performance -- this
had very different emphasis in the US than in Britain. In the US it
came almost exclusively to mean psychometric testing whereas in
Britain it included fatigue research, working conditions and job
design, all of which were referred to as "human factors".
Traditionally providing the 'fit' between the environment and the
person by altering the environment has been called 'ergonomics'. In
the UK in recent years, however, Human Factors has embraced the
broader context of work practices, including considering personnel
and not just the redesign of the work environment. So in the USA
Human Factors is Ergonomics in the UK, but in the UK human factors is
ERGONOMICS + SELECTION + TRAINING.
'Fitting the person to the environment' is the responsibility of
selection and training, whilst ergonomists 'fit the environment to
the person'. There is therefore, a complementary relationship between
ergonomics and selection/training. Although they share a common goal
-- often only one is needed for a solution. Market forces, financial
constraints, management policy, and so on all influence which of
these a company emphasises. Furthermore, whereas selection and
training relate explicitly to the human resource problems at work,
ergonomics is important not only for designing the work environment,
it applies to any environment and any made object. Ergonomics is also
important when you are a company which manufactures products for
other work environments (e.g. computer manufacturers).
In the 1950's Prof. Alec Rodger encapsulated the definition of the
field of occupational psychology in the slogan
"Fitting the man to the job and the job to the man (FMJ/FJM). This was realised as:
fitting the man to the job through
occupational guidance,
personnel selection,
training and development
and
fitting the job to the man through
methods design,
equipment design, design and
negotiation of working conditions and (physical and social) rewards.
(Holloway, W. , 1991)
Rodger's definition has been critiqued as it does not take into account the organisation in which the 'man' works.
To sum up, Human Factors is largely concerned with fitting the job to the 'man' through redesign of the environment and/or work practices and work support.
Although in this course we are not concerned with selection and training, it is worth noting that there is a complementary relationship between these activities, and that often user groups are selected to fulfil certain requirements which are specified by the working environment.
The history of human factors work is linked to the political and
economic climate in which workers find themselves.
HF has its roots in WWI fatigue and placement work, early work on
time-motion analysis, and organisational psychology and beyond,
depending how broad your outlook is.
Brown (1977) traces the roots of Human Factors to the late 19th
century and the emergence of the (non-applied) discipline of
experimental psychology. For example, Galton in the 1880's
looked at interpersonal differences in intellect and mental imagery
and Catell in 1990's looked at differences in sensory motor
capabilities, reaction times and problem solving abilities which
provided a foundation for IQ tests and personality trait work. This
laid the foundations in turn for psychometric testing, a practice
still popular within vocational and personnel work.
As educationalists, Ebbinghaus and Binet were the first
people to look at individual differences and intellectual ability. To
a great extent, the study of individual differences has fallen into
disrepute within mainstream cognitive psychology, the notion that
traits are singular and measurable being saved for Cosmopolitan
questionnaires. However, developments in complex factor analysis and
improvements in contextualised analyses of performance have offered
ways of looking at the interaction of certain individual
characteristics with particular contexts (Sternberg). These more
recent trends however stress the possibility for change and do not
attempt to make the long term predictions which original work in IQ
did.
Whilst experimental psychology was developing in the UK, within the
USA two distinct engineering approaches to the study of human
behaviour were developing.
The Gilbreths (late 19th and early 20th century) pioneered the
concept of the motion study as a technique for improving worker
efficiency. They believed that any task could be broken down into
individual motions or manipulations, and that it was the nature of
these motions that determined overall efficiency. Remember this when
we discuss task analysis. There are two interesting books on this.
One, by Gillian Gilbreth, The one best way, helps establish
her as one of the first engineering psychologists, as one of the
first female psychologists, and as an entertaining writer. The other,
by their oldest son, Cheaper by the dozen, illustrates how
their work influenced their family life. This has also been made into
one of the few movies to have a HF experts as the protagonists.
Frederick Taylor was a contemporary of the Gilbreths. He had
an alternative approach called the time study. Taylor believed that
skilled behaviour should be defined more in terms of the sequencing
of motions made by an operator and the speed at which they were
carried out rather than in terms of the individual units of movement
themselves. Taylor's technique consisted of rationalising a
particular task into its most economical sequence of actions and
determining the maximum rate for these actions which would not
overtire the operatives performing them. Taken together, time and
motion studies proved to be a powerful management tool for
determining realistic work schedules, setting basic pay scales and
generally improving the efficiency of the production process.
Although this was associated with reducing staff and became a highly
politicised movement because of the emphasis on the output and not
the worker.
Munsterberg (1913), looked at "economic psychotechnics".
Note this was all about changing the worker. There were
organisational changes also &emdash; for example, Hawthorne
and fatigue work, Rowntree. Concentration on anthropometric issues in
the pre-WW1 times, looking at can something be used, for example,
desk heights and lighting. Brought together engineering,
physiological and psychological approaches.
Note also that there was a USA versus Britain split in this kind of
work. In Britain the force of the Trade Unions meant that management
efficiency issues were balanced with consideration of work
environments from the worker's perspective. However, the political
problems caused by the use of time and motion studies and the
dehumanisation of the worker left a tendency to mistrust ergonomists
and human factors workers. In more recent years, with the development
and promotion of user-centred design issues this bad reputation has
finally been reduced.
The outbreak of WWI provided a stimulus for these and other early
human factors studies. The need to expand the armed services to many
times their pre-war size meant that large numbers of civilians had to
be conscripted and sorted according to their abilities. Large scale
testing was undertaken to sort people into being pilots,
telegraphers, etc.
Also women took the place in the factories of the men who were at the
front line. They had to learn skilled trades rapidly and were faced
with workloads which far exceeded normal capacity due to the need for
war materials to keep the armed forces supplied. This was a highly
motivated work force. Many people offered to work overtime, sometimes
working up to 100 hours per week. The unexpected results of this was
the decline in production due to ill health and low morale, despite
the initial motivation. To combat this, the Department of Scientific
and Industrial research and the Medical Research Council were asked
to investigate the conditions of the industrial workers in 1917 and
shortly afterwards the Committee on the Health of Munitions Workers
(later the Industrial Fatigue research Board) was appointed to
investigate the causes of fatigue among munitions workers. Under the
direction of this Committee research workers from the biological
sciences were called in for the first time to investigate the work
behaviour in real industrial settings.
Inter-war years: slow period for Human Factors. However there were
two important developments during this time. The foundation
of the Cambridge Psychological Laboratory in 1921 and the
so-called Hawthorne studies carried out during the late 1920's
and the early 1930's. The Cambridge Lab was a non-profit making
organisation designed to continue the collaboration of researchers
and practitioners begun during the war by making the results of
physiological and psychological research available to industry.
The Hawthorne experiments were conducted by Mayo et al. at the
Hawthorne works of the Western Electric Company. These were extremely
important experiments that were aimed at determining the effects of
levels of illumination of performance efficiency. The studies showed
that the most important factor in determining performance efficiency
and productivity was psychological rather than physiological in
nature.
In the 30's with the economic recession, Human Factors work fell
into a hiatus. There were so many applicants for each job that
improving working conditions was not a necessity for most
organisations.
However, WWII broke out and again workers needed to be allocated and
trained quickly and so work in HF and selection once again took off.
In UK there was an acute shortage of aircraft so in 1942, the
Production Efficiency Board of the Air Ministry was set up to advise
on the best means of utilising staff. They introduced time and motion
studies and personnel training schemes, and in the field of
environmental psychology and physiology the Industrial Health
Research Board (formed in 1929 from the old Industrial Fatigue
Research Board) was called in to advise on working hours, rest pauses
and environmental conditions in the factories. Workers were however
under much more pressure than they had been in WWI &emdash;
servicemen had to function equally efficiently in desert conditions,
tropical jungles or Arctic convoys, and had to use equipment that had
increased considerably in complexity, such as radar, sonar, high
altitude aircraft, sophisticated weaponry and sub-marines that
imposed much greater demands on operator abilities.
Various bodies were set up to advise on the medical, physiological and psychological requirements of design &emdash; for example the Medical Research Council's Applied Psychology Unit (MRC/APU), the Climatic and Working Efficiency Research Unit (Oxford) and the Division of Human Physiology at Hampstead. Human factors knowledge was still fragmentary at this stage and limited in practical applications. Existing studies of fatigue were entirely about muscular fatigue rather than mental workload and skilled behaviour was reduced to conditioning and simple reaction times. Most of the work was lab-based and not highly generalisable. The first simulator was built at the APU to observe pilots working for long hours, and fund that to a large extent performance depended on the arrangement and interpretation of displays as well as controls, so had to move away from pure muscular fatigue interpretation to cognitive one. This interest in the perceptual elements of skilled behaviour represented an important departure from conventional work study methods that had previously dominated the consideration of motor abilities. It marked the beginning of a change of attitudes towards the design of machine for human use. It was henceforth realised that it may be necessary to modify the characteristics of the machine to suit the capabilities and limitations of the operator in addition to selecting and training the operator to fit the machine. (This had been seen in other circles earlier &emdash; particularly sales &emdash; see the design books. But this was not systematic. However, this illustrates Thomas Green's point that results from different areas are often not seen as relevant to each other).
This change in design orientation represents the birth of human factors as a distinct disciple in its own right.
The actual birthdate of the Ergonomics Society is 12 July 1949, when a meeting was held at the British Admiralty at which an interdisciplinary group was formed (called the "Human Research Group") (Murrell, 1980). Later at a meeting on 16th February 1950 the term ergonomics was coined. From the Greek Ergon = work and Nomos= Natural laws. The society includes anatomists, engineers, physiologists, psychologists, industrial medical officers and others.