Copyright 1998. David Gilmore, Elizabeth Churchill, & Frank Ritter

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.

Aim: Define, describe and locate human factors practice

(part 3 of 5)

Locating Human Factors as a discipline

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.

Human Factors as a discipline: A historical perspective.

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.

Lecture 1 Continued...

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