A primer on the research issues and techniques for each human factors subdiscipline, this book brings together the works of some of the best human factors researchers, from Wickens to Willeges and from Boehm-Davis to Mital. KEY TOPICS: Each of the fourteen chapters, covering a range of topics from consumer products, to medical devices, to military systems, is written by a noted expert in the area, and is a brief tutorial on the research issues, techniques, and apparatus used when conducting research in a particular discipline. MARKET: For researchers in the field of human engineering.
(NOTE: Biographies and References follows each chapter).
1. The Evolution of Human Engineering: A Selected Review.
1900-1920. 1920-1940. 1940-1960. 1960-Present. Where Are We Going?
Where Do I Start? Basic Human Engineering Research. Applied Human Engineering Research. Finding a Problem. Filling a Gap in Existing Research. Resolving Contradictory Experimental Results. Explaining the Occurrence of an Unexplained Fact. Reading for Problems. Turning a Problem Into a Testable Hypothesis. Some Reasons for Problems that Aren't Testable. Conducting the Experiment. Threats to Research Validity. Threats to Internal Validity. Threats to External Validity. Summary. Suggestions for Further Reading.
Introduction. Stages in Experimental Research. Stage 1: Problem Definition. Stage 2: Planning. Stage 3: Conduct of Research. Stage 4: Data Analysis. Stage 5: Interpretation. Some Experimental Designs. Two Group Designs. Multiple Group Designs. Data Reduction Designs. Sequential Experimentation. Conclusion.
Usability. History. Rationale. Conducting a Usability Test. Error Analysis. Test Subjects. Who are the users? How many? Tools of the Trade. Keystroke records. Video Records. Eye Movement Tracking Think Aloud Protocols. User Surveys and Checklists. Assessing Costs and Benefits. Contextual Research. Concluding Remarks. Appendix 4-1: Sample User Profile. Appendix 4-2: Blank User Profile Worksheet. Appendix 4-3: Selecting an Eye Tracker.
Introduction. Research Domains. Flight Control. Procedures. Pilot Judgment and Decision Making. Crew Interactions and Cockpit Resource Management. States Experienced in Pilot Performance. Influences on Operator Performance. Research Methods. The Experimental Method. Protocol Analysis. Surveys. Incident Analysis. Accident Reports. Modeling Literature Reviews. Research Methodologies in Consort. Statistical Inference. Summary.
Introduction. Who Are Older People? Research Issues. Which Characteristics of Older People Are of Interest. Age-Related Changes in Sensory Functioning. Age-Related Changes in Psychomotor Functioning. Age-Related Changes in Anthropometry and Physical Function. Age-Related Changes in Cognitive and Intellectual Functioning. Age-related changes in motivation and attitudes/beliefs. Research Design. Stratified Designs. Longitudinal Designs. Methods for Studying the Effects of Aging Useful General References on Aging.
Perspective. Introduction. Field Surveys and Evaluations. Clinics. Focus Groups. Mall/Licensing Office Surveys. General Laboratory Studies. Secondary Control Evaluation. Response Time to Displays. Rear Lighting Design. Ingress/Egress, Trunk, and Underhood Access. Driver Anthropometry Studies. Component Evaluation - Seat Comfort. Computer Testbeds-Rapid Prototyping of Driver Interfaces. Specialized Laboratory Studies. Thermal Comfort. Vehicle Sound Measurement. Crash Tests. Driving Simulation. Advice and Comments. Proving Grounds Experiments. Advice and Comments. Experiments on Open Roads. Individual Cars With No or Minimal Instrumentation. Instrumented Cars. Operational Field Tests. Advice and Comments. Lessons from My Experience. Which Method is Best? Maintain an Automotive Context. Collect Data on the Road When Possible. Test Drivers of All Ages. Videotape Participant Interactions. Closing Remarks. Suggestions For Further Reading.
Introduction. Telecommunications Equipment and Service. Categories of Users. End Users. Expert Users. Special Usability Attributes Usability Principles as Applied to Telecommunications. Usability Methodologies as Applied to Telecommunications. Special Usability Methods Speech Quality. Telecommunications Network Transmission Objectives. Text-To-Speech Quality Measurements. Measurement of Speech Intelligibility Automatic Speech Recognition.Interactive Voice Response. Simple Voice Telephony Services. Distinctive Sounds for Telephone Tone Ringers. Additional Telephone Design Issues. Complex Voice Telephony. Usability. Evaluation of Emerging Technologies. Video Communications. Multimedia Communications. Summary of Methodologies. The Future. Additional Readings in Telecommunications.
Introduction. Nature of Consumer Products Research. Informal Techniques. Focus Groups. The "Rapid Fire" Review Technique. Voice of the Customer. One-Person Research. Formal Techniques. One Person Research. Two-Person Research. The Reality of Usability Testing. How to Get Buy-in from Management. Appendix.Typical Screener.
Introduction. Scope of the Chapter. Hardware. Major Research Issues. Anthropometry Measures and Methods. Human Performance Measures and Methods. Software Interface. Major Research Issues. Measuring User Interface Effectiveness. Issues in Evaluating User Interface Effectiveness Users. Individual Difference Variables. Methodological Approaches. Software. Major Research Issues. Measures Computed from the Software. Measures Computed from Human Performance. Methodological Approach Summary. Issues For Further Research.
Industrial Ergonomics and Its Scope. Scope of This Chapter. The Nature of Research. Experimental Design. Experimental Variables Measurement of Experimental Variables. Types of Human Strengths. Electromyography (EMG). Joint Angles and Body Posture. Measurement of Body Size Parameters. Heart Rate. Oxygen Consumption. Core Temperature. Sound Pressure Level. Illumination. Vibration. Instrumentation. Human Strengths Joint Angles and Body Measurements. Heart Rate. Oxygen Consumption. Sound Level. Illumination. Core Temperature. Vibration. Major Research Issues. Human Strengths. Hand Tools. Anthropometry. Noise. Illumination. Musculoskeletal Injuries.
Introduction. Human Factors in Health Care Quo Vadis? Health Care Personnel Shortages. Shortcomings in Medical Education. Medical Information and Communication System Deficiencies. Diagnostic and Treatment Equipment Deficiencies. Assessment of Medical Procedures on Patient Performance. Health Care Technology Assessment. The Methods of Technology Assessment. Technology Assessment and Ergonomics Practice. Summary. Resources. Public and Private Organizations. Research in Progress Publications. Additional Information. Biography.
Overview. The Aircraft Carrier. Rapid Deployment Forces. Uniqueness of the Military. Systems Considerations. Personnel/Selection Considerations. Training Considerations. Military Personnel. Funding of Human Factor Engineering Related Activities. Human Factor Engineering's Areas of Responsibility. Support for a Human Factors Engineering Technical Group. Development of Specifications and Standards. Crew System Ergonomics Information Analysis Center. System Development. Selected Systems. Test and Evaluation. Statistical and Methodological Issues. Maintenance. HFE Tools/Techniques Developed/Utilized. Catalogs/Integration of Tools. Questionnaires, Surveys, Interviews, and Protocol Analysis. Operator Workload (OWL) Measurement. Performance Test Batteries. Simulation. Environmental Effects. Sustained Operations. Acceleration. Decision Making Under Stress. Use of Human Subjects in the Military. Women in the Military. Opportunities for Involvement in DOD Programs. Future Directions of Military HFE. Simulation. Modeling. Workload/Situational Awareness. Automation. Expert Systems. Personnel Utilization. Maintenance.
Overview. Training Effectiveness. What is Training Effectiveness? The Nature of Training Effectiveness Research. Individual Characteristics. Organizational Characteristics. Motivation. Training Program. Transfer of Training. Measures Used to Assess Training Effectiveness. Example of a Training Effectiveness Measures Study. Summary. The Training Research Tool Box. Theory. Measurement. Statistics. Experimental Design. Odds & Ends Issues. Conclusion. Appendix 14-1. Appendix 14-2. Appendix 14-3. Index.
It was with considerable trepidation that I undertook the task of discussing the evolution of human engineering (HE). How does one discuss the undefinable? Licht, Polzella and Boff (1989) extracted 74 different definitions from the literature, definitions for terms such as: human factors, ergonomics, human engineering, human factors psychology, human factors engineering, applied ergonomics, and industrial engineering. The most inclusive terms are human factors and ergonomics.
In the 1960s an d 1970s, the former term was usually associated with psychology (mental workload and cognitive issues) while the latter term was usually associated with physical work. Human Engineering and its analog Applied Ergonomics are concerned with the application of data derived from their respective traditions to the design, test and evaluation of equipment or systems. During the 1980s and 1990s, the boundaries between the terms Ergonomics and Human Factors have blurred as the use of the term ergonomics (which originated in Europe) increased in the United States. Christensen (1987) and Kroemer, Kroemer and Kroemer-Elbert (1994) consider the terms synonymous. International Ergonomics Association: Origin of; Kroemer, Kroemer and Kroemer-Elbert (1994) attribute the origin of the term ergonomics (ergos =work and nomos=laws) to K.F.H. Murrell; in 1949. They also note that, Monod and Valentin (1979) reported the use of an analogous term 100 years earlier in Poland. In June 1949,
Murrell hosted a meeting in the British Admiralty. This meeting led to the formation of the Ergonomics Research Society. Ten years later the International Ergonomics Association was formed and in 1961 it held its first formal meeting. The origin of the Human Factors Society (HFS) follows a similar pattern. In 1955 a planning meeting was held in Southern California, and two years later the first national meeting was held in Tulsa, Oklahoma. In January 1993, recognizing the increased use of the term ergonomics and reflecting the varied interests of its members, the HFS added the term ergonomics to its title and became the Human Factors and Ergonomics Society (HFES).
Human Factors Society: Origin of; Ergonomics: Origin of; The material that follows represents a limited examination of a very broad area which incorporates a wide variety of disciplines. Human Factors/Ergonomics can be viewed from many perspectives. However, there is an interesting parallel in the evolution of Human Factors and Ergonomics: both have had considerable military support and experienced a major growth spurt during and immediately after World War II; (WWII). Accordingly, the bulk of the following section reflects the interaction between the military (United States Department of Defense;, DOD) and Human Engineering. 2.0 1900-1920 Human Factors: Synergism With DOD; Hutchingson (1981) describes the first prehistoric man to use a tool for his protection or service as the founder of human factors thinking. Indeed, a study of people-powered farming tools (e.g., ax, sickle, scythe) reveals changes over time that in formally reflect the system development cycle from requirements definition through limited production, test and evaluation and system retirement. However, the first organized effort in the profession is usually attributed to F.W. Taylor;, who in 1898 restructured an ingot loading task at Bethlehem Steel (Adams, 1989). Before the restructuring, the average daily load moved per worker was 12.5 tons. However, Taylor demonstrated that by use of appropriate selection;, training;, and work-rest schedules;, an individual could move 47.5 tons per day and do so repeatedly.
Subsequently, he designed a series of shovels for handling different types of materials. Taylor delineated basic principles of work design and formalized time and motion studies, which became the basis for today's task analysis. Frank Gilbreth;, one of Taylor's students, is perhaps best known for his improvements to the bricklayer's task. Additionally, Sanders and McCormick (1993) report that during the earl y 1900s Frank and Lilian Gilbreth; also studied skilled performance, workstation design and designs for the handicapped. Except for the type of work cited above, Hugo Munsterberg;'s investigations of industrial accidents and the efforts of Western Electric at the Hawthorne Plant 3, little progress was made in HE during this period except for interactions with the DOD. Hawthorne Effect; The interaction between HFE and DOD has historically been synergistic. Indeed, as reported by Christensen (1987, p.5), "to their credit, it was the authorities in the Department of Defense who first actively supported the human factors profession.
Even today many industries are not yet at the stage of development with respect to human factors that DOD was a generation ago." Driskill and Olmstead (1989, p.43) trace psychology's initial involvement in the DOD to Robert Yerkes;, who described the World War I (WWI) efforts in selection;, training;, motivation;, and aviation; as the first attempt to deal "scientifically and effectively with the principle human factors in military organization and activity. This effort involved some of the early leaders in psychometrics, including Thorndike and Thurstone. During WWI, psychology's major contribution was in the area of selection; and classification of recruits; During this period, the Army Alpha; and the Army Beta Tests; were developed to evaluate the abilities of English-language literates and English-language illiterates (Taylor and Alluisi, 1993). Aviation Psychology was responsible for the development of what may have been psychology's first applied test battery, which was used to predict flying aptitude (Taylor and Alluisi, 1993). Finally, as ever higher altitudes were sought, the deleterious effects of hypoxia and hypothermia on aviators' performance were examined. Selection: Army Alpha; Selection: Army Beta; It is interesting that during WWI, Yerkes headed the Committee on Psychology of the National Research Council (NRC), an antecedent of today's Human Factors Committee of the NRC.
This committee, in response to DOD concerns, has produced many excellent reviews in the area of HFE including: Research Issues in Simulator Sickness (McCauley, 1984), Human Performance Models of Computer-Aided Engineering (Elkind, Card, Hochberg, and Huey, 1989); Human Factors Specialists' Education and Utilization: Resu lts of a Survey (Van Cott and Huey, 1992); and Workload Transition: Implications for Individual and Team Performance (Huey and Wickens, 1993). World War I; DOD; NRC; Simulation; Workload; 3.0 1920-1940 .i.Driving Behavior: Early Experiments; Increased use of the automobile; after WWI, created an impetus for human factors studies of driving behavior;.
Forbes (1981) provides an interesting review (including the following citations) of early research beginning with work at Ohio State in 1927. A 1930 text by Weiss and Lauer describes epidemiological studies of automobile accidents, laboratory studies of estimated velocity, a moving belt "miniature highway" driving simulator and social characteristics of traffic regulation violator s. Perceptual issues examined included head movement, foveal and peripheral vision reaction time; and vision requirements. In 1938, Cobb concluded that correlational analysis of auto accidents, psychophysical testing and interview data could not b e used to identify "accident-prone individuals". In 1939, Forbes concluded that the characteristics of normal drivers needed to be examined to determine what caused them to have accidents. Studies at Iowa State University (Lauer and Helwig, 1932) produced recommendations regarding the colors of signs. Mills (1933) examined sign visibility at night.
Within the DOD, a hiatus in HFE activity occurred between WWI and WWII, except in the area of aviation systems. Dempsey (1985) provides a fascinating overview of the work of aviation pioneers during an era in which both man and machine redefined the limits of aviation. In the U.S. Army Air Force (AAF, in 1947 it became the USAF), the emphasis was primarily medical/physiological, and fell under the leadership of Captain (later General) Harry Armstrong, namesake of the USAF Armstrong Laboratory ;. Researchers, using both animals and man, examined the effects of altitude on performance. In 1935, Captains Armstrong and Stevens set a world altitude record of 72,000 feet during a flight in a National Geographic Balloon. During this period, the effects of accelerative forces were also examined. Angular accelerations were produced by a 20-foot-diameter centrifuge, while a swing was used to produce linear accelerations. As early as 1937, a primitive "G-suit;" had been developed and a recommendation was made to designers that in an aircraft exceeding nine Gs the pilot should be placed in the prone position.
Today, more than 50 years later,research on the reclining seat; continues, although with better simulators, higher G onset rates, and greater concern for both physiological and cognitive functions (Deaton and Hitchcock, 1991). The initial work on the effect of anthropometry on aircraft design and crew performance also began in 1935. This work continues today as the Armed Forces attempt to accommodate more fully both women and men into military cockpits and other systems.
During the early 1930s, Edwin Link marketed his aircraft flight simulator as a coin-operated amusement device (Fischetti and Truxal, 1983). However in 1934, the Army Air Corps purchased its first flight simulators and the foundation was laid for the development of flight simulation technology. Simulation and simulator technology have progressed considerably since then, but today's virtual reality environment is a descendant of Link's Trainer. Anthropometry: Aircraft Design; 4.0 1940-1960 Simulator: First Aircraft Simulator; In 1939, as clouds of war gathered over Europe, the Army established a Personnel Testing Section, while the NRC created the Emergency Committee on Psychology to focus on personnel testing and selection. In 1941, The Army Air Force Aviation Psychology Program;, directed by John Flanagan, was created to aid in selection and training of aircrew (Driskell and Olmstead, 1989). During the war, the Army General Classification Tests (AGCT); were developed and used in the selection;, classification, and assignment of 13 million personnel by the end of the war. Based on the success of these testing programs, the DOD; developed the Armed Forces Qualification Test (AFQT);, a test of mental ability, that in 1950 was adopted by all the Armed Services.
In 1974, the AFQT was incorporated into the Armed Services Vocational Aptitude Battery (ASVAB);, which is administered annually to approximately 1.5 million potential recruits (Driskell and Olmstead, 1989). Computerized Adaptive Testing (CAT) ; versions of the ASVAB are currently being evaluated (Taylor and Alluisi, 1993). Personnel Selection; Similar efforts in the area of aircrew personnel selection led to the Air-Crew Classification Test Battery;, which provided predictions of success in training and combat (Taylor and Alluisi, 1993). Like other personnel tests, this battery used paper and pencil tests to evaluate aptitude and ability, however various apparati were used to measure coordination and decision time. Taylor and Alluisi note that because the predictive ability of paper-and-pencil tests appears to have been maximized, personnel selection is again focusing on apparatus-based testing. The return to apparatus-based performance testing has been greatly facilitated by the increased availability of personal computers. Readers interested in a recent comprehensive overview of selection, classification, and placement in the military services should consult Steege (1991). Human Factors: First Texts; In addition to test development efforts during WWII, HFE personnel actively assisted designers of military hardware. A good overview of the areas addressed during WWII is contained in an Office of Naval Research; (ONR) sponsored text by Chapanis, Garner, Morgan, and Sanford (1947), which was assigned a "Restricted" classification during the war. The table of contents includes topics similar to those found in today's introductory HFE textbooks: psychophysics, design of experiments;, working environment (temperature and humidity, acceleration;, motion sickness;, vibration;, noise, etc.), arrangement of equipment, speech, communication; and hearing, auditory systems, optical illusions, legibility, display problems and psychophysical research. Chapanis et al. also describes the effect of perspective illusions on radar presentations and average ranges for spotting aircraft under winter skies in Britain. The work of Chapanis et al. was followed by the ONR sponsored Handbook of Human Engineering Data for Design Engineers (Naval Training Devices Center, 1949), prepared by the Tufts College Institute for Applied Experimental Psychology. This handbook was perhaps the first effort to consolidate knowledge in the field of H FE into one source. It was followed, in 1963, by the first edition of the Human Engineering Guide to Equipment Design by Morgan, Cook, Chapanis, and Lund and a later second edition by VanCott and Kinkade (1972). These works were precursors to the Engineering Data Compendium (Boff and Lincoln, 1988), and the Handbook of Perception and Human Performance (Boff, Kaufman and Thomas, 1986). Over the years, the DOD has supported the development of documents providing general knowledge in HFE, as well as documents in specialty areas such as submarine (NRC, 1949) and aircraft environments (ONR, 1978), underwater performance (Shilling, Werts, and Schandelmeier, 1976), and anthropometry of USAF women (Clauser, et al, 1972). World War II; also engaged HFE personnel at the AAF Aeromedical Research Unit;, Wright Field, in a wide variety of activities including the development of: human tolerance limits for high altitude bailout, automatic parachute opening devices, cabin pressurization schedules, pressure breathing equipment and protective clothing; for use at high altitudes, G-suits;, and airborne medivac facilities. They also developed the first anthropometry; data base for aircrew and initiated work on ejection seats (Dempsey, 1985). In the late 1940s and early 1950s, commercial aviation was in its infancy. Ross A. McFarland; effected a technology transfer as he integrated aviation related knowledge gained during WWII with other areas and wrote two texts dealing with human factors in air transport design (1946) and HF in air transportation (1953). Progress was also made in the automotive area when in 1949, the Institute of Transportation and Traffic Engineering was established at the University of California, Los Angeles. In 1954, McFarland and Moseley published a major text in this area entitled Human Factors in Highway Transport Safety. Institute of Transportation and Traffic Engineering: Establishment of; Human Factors: First Bell Labs Group; While researchers in the area of audition had been at Bell Laboratories since 1925, it wasn't until 1946 that the first human factors group was established at Bell Laboratories (Bailey, 1989). This group advised designers on topics ranging from the weight of telephone handsets; to the layout of keys for the push-button telephone pad;. In 1967, a second human factors group was organized at the Bell Human Performance Technology Center. This group was established to ascertain that good human factors principles were applied not only to Bell System customers but to Bell System employees (particularly those working with computer systems). Despite its separation into smaller companies, many HFE personnel are today employed by relatives and descendants of the Bell System (e.g., AT&T;, AT&T Bell Laboratories;, Bell Communications Research;, and BELLCORE;). Today, other communications corporations have similar groups. Throughout the 1950s and 1960s, HFE personnel contributed to the accommodation of man in jet driven aircraft and explored the edges of space in rocket propelled aircraft. The DOD; invested heavily in these areas. During that era, only DOD aviators were considered for Project Mercury and they received part of their training in DOD facilities. Today, descendants of DOD's technologies fly aboard the NASA; shuttles. Space Shuttle; Under the seas, the nuclear power industry was born as Navy personnel were deployed aboard nuclear powered submarines. The nuclear submarine, with its capability for remaining submerged for months, brought unique habitability problems (Barton and Webrew, 1957). Nuclear Subs: Habitability Problems; During these years, the development and testing of larger and more complex systems was undertaken by both military and civilian agencies. Many of these developments (including the following) are well described by Parsons (1972). The Laboratory of Aviation Psychology of Ohio State University;, under the guidance of Paul M. Fitts;, conducted a series of experiments on Air Traffic Control (ATC);, with the sponsorship of the USAF Aerospace Medical Laboratory; (now Armstrong Laboratory;). These experiments had a military, rather than a civilian, focus and were performed in response to problems encountered during the Berlin airlift and the Korean War. Subsequently, related work was performed by the Systems Development Corporation, the MITRE; corporation and the University of Illinois. Eventually the work transitioned to the National Aviation Facilities Experimental Center (NAEFEC); of the Federal Aviation Agency, now known as the Federal Aviation Administration (FAA );. Thus the ground work for the existing ATC system had its origins in military aviation. Today, the FAA's National Airspace Program; (1990) to upgrade the ATC system is underway and involves many human factors efforts. 5.0 1960-Present Human Factors: Computing Systems; During the 1960's, the application of human factors to computing systems was primarily limited to the traditional ergonomics role of designing interface hardware (e.g., the keyboards for computer terminals) (Boehm-Davis, 1994). Some human factors comparisons of programming languages and batch versus timesharing systems were reported by Sackman (1970), but serious empirical research in other areas did not appear until after 1970 (Boehm-Davis, 1994). Human Factors: Comparison of Programming Languages; PC; Icons: Origin of; Windows: Origin of; Pull-down Menus: Origin of; Human Factors: First HCI Texts; HCI: Origin of The early seventies saw the introduction of the Personal Computer (also known in those days as microcomputers). The earliest microcomputers required operators with programming skills. The personal computer brought with it the rapid emergence of appl ications software (word processing, graphics packages, etc.) rapidly emerged and the special purpose microprocessor evolved into the general purpose PC. In 1970, the Xerox Palo Alto Research Center (PARC); was established to perform research in " intelligent information systems" (Wasserman, 1989). PARC's innovations included the development of icons, windows, pull-down menus and mouse interactive systems. These interactive techniques have been adapted for use in Apple's Macintosh; and Microsoft's Windows. PARC also developed the concept of "WYSIWYG;" (What You See Is What You Get). The 1970's also saw the emergence of the first, serious scientific inquiry into the human factors of the human-computer interface (Boehm- Davis, 1994). Design of Man-Computer Dialogues (Martin, 1972) was the first book to identify human-computer interface as an independent area of study (Boehm-Davis, 1994), while The Psychology of Computer Programming (Weinberg;, 1971) was the first publication to emphasize the importance of controlled experimentation in evaluating performance in computer-r elated tasks, such as programming. In turn, the term Òsoftware psychologyÓ first appeared in Ben Shneiderman's Software Psychology (1980) and refers to the study of psychological factors effecting the performance computer users. Nickerson (1992) provides additional historical insight into the increasing role of human factors in the development of the human- computer interface (HCI). He reviewed the contents of the journal Human Factors for 1965, 1975 and 1985. In 1965, only one of the 58 articles published was related to computers or computer based systems, in 1975 only two of the 62 articles were related to HCI. However by 1985, approximately 1/3 of the 55 articles addressed HCI. In 1979, Ramsey and Atwood, with ONR sponsorship, published a comprehensive review of the HCI literature. Smith and Mosier (1986), with USAF sponsorship, published the first comprehensive set of user interface design guidelines. In 1983, Card, Moran and Newell published the Psychology of Human-Computer Interaction, which examined the cognitive processes that humans use when using a computer interface. In 1985, Shneiderman published Designing the User Interface: Strategies for Effective Human Computer Interaction, which offered practical guidance for developing hardware and software human computer interfaces. Wasserman (1989) provides some fascinating insights into the role of human factors and industrial design in the marketplace during the 1970s and 1980s. The late 1970s and early to mid 80s was a crisis era for the Xerox corporation, whose market share of the copying machine market had fallen from 82% in 1976 to 41% by 1982 (primarily due to Japanese competition). As part of its reorganization, Xerox combined the human factors and industrial design groups into one department called the Industrial Design/Operability. Thus Xerox, as a matter of corporate policy, placed considerable emphasis on system "operability". Focusing on the characteristics of the user, and applying the principles and techniques developed by PARC, Xerox captured 55% of the copying machine market by 1985. In the 1970s and 1980s, several factors converged within DOD to place additional emphasis on the role of humans. These included the evolution of the systems approach, more complex and costly systems, the cost of manpower, and the establishment of an all-volunteer force. In this regard, Meister (1976) clearly describes the human as a subsystem, whose behavior must be understood within the context of that system. HFE personnel were increasingly involved in the development and evaluation of training devices and simulators, particularly those used in aviation. Typical of that era was the work of: Orlansky and String (1980) on the cost effectiveness of flight simulators for military training and Jones, Hennessy and Deutsch (1985) on human fact ors aspects of simulation. DOD: Increased HF Emphasis in 70Õs; On March 28, 1979, an operator induced accident at the Three Mile Island; nuclear power plant increased the visibility of human factors. By the end of the event, the reactor core was destroyed, more than one million gallons of radioactive water filled the containment building, radioactive gas was released into the atmosphere, 90 percent of the fuel rods in the reactor core were damaged, and thousands of local residents were evacuated. Let's briefly examine what happened (details are contained in Malone, et al. 1980). At approximately 4 AM, the feedwater pumps that supplied water to the steam generators failed, which automatically turned off the generators. Without this cooling water, the temperature of the reactor coolant increased, which led to a build up of pressure in the pressurizer. The pilot-operated relief valve (PORV) opened to relieve the overpressure and failed to reseat (a failure, which took 138 minutes and a new shift-supervisor to recognize). With the temperature still rising and the loss-of-coolant, the preprogrammed control rods dropped to halt nuclear fission and the emergency feedwater pump started pumping water into the steam generator. The operator s misinterpreted what was happening and reduced the flow of coolant, which resulted in the devastating effects described previously. What role did the human operator play in this accident? First, if the operators had not intervened, the situation might have been limited to a minor incident (but we will never be certain). Second, when they did intervene, they were dealing with confusing, unintegrated information. The report of the President's Commission stated: "The information was presented in a manner to confuse operators" (Kameny, 1979, p.29). You will recall from the above summary that the PORV had failed in the open posit ion. During the incident, the operator noted that the PORV indicator light was not illuminated which he interpreted as meaning that the PORV was closed, since according to the label below the light "Light ON" indicated OPEN. Unfortunately, the illuminated PORV light did not tell the operator about the position (OPEN/CLOSED) of the PORV, only that power had been sent to the PORV. However, in the operator's mental model of the system, by implication and with the lack of any information to the contrary, an unlit PORV light was assumed to mean that the PORV was closed. Inadequate, inappropriate feedback was the design deficiency in this particular case. Given sufficient time, the operators would eventually have determined the nature of the problem. However, problems in nuclear power plants can rapidly become disastrous accidents. Note that 100 unprioritized alarms sounded or were displayed to the operators within three minutes after the loss of the feedwater pumps. More of the 750 alarms were activated as the incident progressed. Thus the system that had been designed to advise the operators of all failures functioned as designed and the operators were faced with the dilemma of distinguishing between cause and effect as the system started to collapse. Three Mile Island; Feedback: Effects of Inadequate; This incident was of such proportions that the U.S. nuclear power industry has not yet recovered, as evidenced by the halt in the construction of nuclear power plants. Unfortunately, lessons were not learned and in the April 1986 the nuclear reactor at Chernobyl; melted down and released 50 million tons of radioactive isotopes into the atmosphere. This early-morning catastrophe also involved human error (Medvedev, 1991). In 1984, a manufacturing accident again brought human factors to the forefront. The leak of a pesticide in Bhopal, India; resulted in more than 3500 dead, 200,000 permanently injured, and genetic changes continuing into the next and possibly future generations. Casey (1993), in a narrative, describes how the operators located leaks by sensing irritation to their eyes and respiratory systems and tried to extract system information from defective displays. Meshkati (1989a, p. 173) characterizes the operations at the facility as "a group of untrained and unprepared operators, working with an unsafe technology in an 'unkind working environment', using unfriendly hardware and unreliable instrumentation, being assembled in an unorganized facility, and supervised by unseasoned managers." Hopefully, lessons learned from this accident will transfer to the chemical industry and to industry in general. DOD: Critical Role of HF; Within the DOD, the critical role of human factors was brought to the attention of Congress in a 1981 report to Congress by the General Accounting Office (GAO);. This report noted that while many DOD weapon systems "may have the capability to perform their missions, it is often of little value because not all the systems can be adequately operated, maintained or supported" (GAO,1981, p. i). Subsequently, the acquisition process was modified when the inclusion of human factors considerations early in the acquisition process was mandated by DOD Instruction 5000.2. The intent of that instruction is clearly stated in the current policy statement: ÒHuman considerations ... shall be effectively integrated into the design effort for defense systems to improve total system performance and reduce cost of ownership by focusing attention on the capabilities and limitations of the soldier, sailor, airman or marine." (1991, P.7- B-1). Figure 1-1 illustrates the DOD's evolving perception of the elements involved in Human Systems Integration (HSI) and clearly states DOD's objective. Note that elements of Human Factors exist under each of the column headings. DOD: Human Systems Integration; The 1980s have seen increased DOD emphasis on developing strategies and techniques to ascertain that the abilities/ limitations of the operator and maintainer were properly considered during system acquisition and development. Specifically: the Army developed MANPRINT (Manpower-Personnel Integration) MANPRINT: Development of; he Navy developed HSI, formerly HARDMAN, (Hardware-Manpower Integration) HSI: Development of; HARDMAN: See HSI; the Air Force developed IMPACTS (Integrated Manpower, Personnel and Comprehensive Training and Safety). IMPACTS: Devlopment of; The MANPRINT; system integration philosophy incorporates the domains presented in Figure 1-1 and establishes procedures mandating their consideration during system development and deployment. This is a people oriented approach to systems developme nt, with significant implications for both DOD and the civilian sectors. Booher (1990) provides a comprehensive overview of MANPRINT's philosophy and methodologies, which have been adopted by other government agencies, foreign governments, and privat e industry. Selected applications of MANPRINT techniques are discussed in the Systems Development section of the chapter on Military Systems. 6.0 Where Are We Going? Howell's (1993) article "Engineering Psychology in a Changing World" contains some projections. He describes the major system design drivers as technology and society. Technological concerns include computerization, automation;, task complexity/speed, and information display;. These concerns translate to the following design issues: human computer interaction;, skill maintenance;, workload transition;, cognitive demands;, "technostress" and organizational consequences among others. The societal concerns include demographic considerations, skill/educational trends, geopolitical change and litigation/consumerism. These societal concerns translate to the following design issues: special populations (e.g., aging and diversifi ed workforces), system requirements, talent shortfall (i.e., lack of appropriately educated personnel), military requirements/.i.technology transfer; and human error/safety. Perrow (1984) argues that as technology "shrinks" the world, what in previous years would have been a localized accident, will now have significant geopolitical/social impact in other areas. Three Mile Island, Chernobyl, and Bhopal are the leading edge of that trend, which provide new challenges to HFE. While we are involved in .i.accident prevention;, we need to develop strategies to reduce the impact of accidents when they occur. Sheridan's discussion (1991) of "New Realities of Human Factors" describes the following sociotechnical areas as posing challenges for human factors: environment, automation and productivity, health, criminal and civil justice, space, air and ground transportation and basic education. He comments that while we may have developed techniques for addressing the simpler one-person stimulus response interface questions, we have not developed techniques to address multiperson interaction problems such as distributed decision making. He believes that the multi- person interaction will become more important as technological systems grow and become more interconnected. "Interconnectedness" is no longer a fanciful thought, but it is here, and the information highway promises more (consider the exponential growth rate of INTERNET;). Sheridan (1991, p.3) describes the dilemma with respect to human factors theory as: ". . . how to keep what is simple and what works for problems at the micro level and add to the paradigm that which is necessary to achieve the best characterization of data, make the best predictions, or contribute the most to understanding or design." Meister's concern about the future of human factors is reflected in his (1989) book, Conceptual Aspects of Human Factors. He describes the goals of human factors as to "describe incisively, predict with precision, control with strength" (p 243). He f eels that, while we are growing as a profession, we have a long way to go as a discipline if we are to achieve the aforementioned goals. Within a systems context, he addresses the broader issues of human factors including the requirements of human factors research, and measurement problems (see also Meister and Enderwick, 1992). He also argues for the development of a human performance data base that would allow us to predict human performance in a systems context. Meister bemoans our inability to establish the worth of human factors. Readers of his text will benefit from a much broader perspective of human factors in systems, appreciate his challenging questions and may be discomforted by some of his positions. Human Factors: Growth a s a Profession; Moray (1993), Van Cott and Huey (1992), and Meister (1989) foresee human factors personnel as members of interdisciplinary teams that include not only engineers and designers but market analysts, sociologists, economists and political scientists. Moray proffers the following areas as requiring human factors attention: population, water, energy, transportation, health care, accidents, pollution and aging. He struck a resonant chord when he discussed transportation: specifically the development of and head-up displays for use in automobiles, and asked are these really the places where we should invest our time and energy? He chides that perhaps, rather than encouraging more vehicles per mile, we should be addressing broader transportation issues including how and when people should travel. Nickerson (1992) provides considerable food for thought in his 1992 book entitled: Looking Ahead: Human Factors Challenges in a Changing World. He avoids the linguistic quagmire by broadly defining Human Factors, as I did in this chapter. In the continuum of human factors literature, Nickerson's work is at one end, while specifications and standards are at the other. He reflects the position taken by Laughery, in his 1991 (p.2) President's Message to the Human Factors Society, that human factors professionals "need to think beyond the boundaries of our own membership, beyond the traditional problems that we work on, and beyond the usual way we do things.Ó Nickerson's book contains chapters on topics as diverse as industry, energy, environmental change, education, transportation, space exploration, biotechnology, information technology, HCI, work and the quality of life. These areas are examined from a HF perspective, in an honest, insightful, carefully balanced fashion. For example, his chapter on transportation contains some chilling data (e.g., by the year 2005, there will be 50 percent more cars on US roads than there were in 1988). Barring major adjustments in transportation utilization, this will lead to an increase in the number of accidents and according to Ervine and Chen (1988-1989, cited in Nickerson) will also result in a fivefold increase in congestion (measured as vehicle hours of delay). It is interesting to juxtapose this prospect with the 1990 report of the Transportation Research Board that despite the long history of developing standards for highway safety, relatively little is known about the cost/benefit ratio of specific improvements. This leaves designers with inadequate data on which to evaluate alternate strategies. Obviously, this is an area in which the skills of HF personnel could contribute significantly. Nickerson's (1993) chapter entitled "Quality of Life" overlaps with the areas cited by Moray (1993) and includes material on designing for special populations, aging, personal safety and health, population growth and increased urbanization, and equity and international cooperation. The world has been described as a global village within which we all must interact. At least part of that interaction involves the transfer of technology between countries. Meshkati (1989a and b) addresses the issue of technology transfer to developing countries and cautions that technology transfer without consideration of micro- and macroergonomics is doomed to failure. He emphasizes the need to integrate the technology with the local resources and infrastructure. On the micro-ergonomic level he calls for consideration of not only workplace design issues (anthropometry, strength, etc.) but also the cognitive aspects of work (stereotypes, the concept of mental models, information processing and decision making). At the macro-ergonomic level, he addresses the effect of cultural variables on technology transfer. These include attitudes towards work, technology, organizations, group dynamics and motivation. He notes that organizational and management structures which work in western cultures may not work in cultures with different historical experiences. Based on the findings of Meshkati and related comments by Moroney and Reising (1992), the impact of cultural and individual differences should be considered when selecting subjects for experiments, and system test and evaluation. The chapters of this book provide domain specific information on what the authors perceive as important to the present and future activities of our profession and our discipline. They address the traditional areas of aerospace, automotive, communication systems, military systems, training, and industrial ergonomics and provide new vistas in both the traditional and emerging areas. Some of the perceived trends include: m Improving consumer products as a result of increased awareness of the importance of "quality" in a more competitive, international market. m An increased emphasis on the importance of effective training in the more competitive international civilian marketplace. m Shifts in the role of human factors in the military from supporting the development of new systems to modifying existing systems and improved training of military personnel. Human Factors: Trends in Profession; m Designing for an aging population. m Designing to improve both the efficiency and acceptance of emerging technologies in the areas of communication, computing systems, and medical systems. m An increased awareness of the role of industrial ergonomics in injury prevention due to work related injuries. Taken as a whole, human factors has much to offer in many areas and can have significant economic and social impact. Clearly, there are and will be sufficient challenges for human factors engineering personnel as technology progresses and the world "shrinks". Historically, like other professions, we have responded to the needs of the marketplace. Indeed, Sheridan ( 1991) suggests that we have become reactive when we should be proactive within the market place. Laughery (1991, p.2), encourages outreaching: "We need to think beyond the traditional problems that we work on, and beyond the usual way we do things." In addition to broadening our horizons and becoming more proactive, I would like to make a modest proposal. I propose that before becoming immersed in a problem, we make a special effort to ascertain, that the "right question" is being asked. Indeed, when we realize that the "right question" is not being asked, then as a minimum, we should pose our version of the "right question" to the decision makers. Thus, perhaps we can focus human factors on what Moray (1993) has termed "humane factors". Human Factors: Growth as a Profession; 7.0 Biography Dr. Moroney served as a US Navy Aerospace Experimental Psychologist for more than 22 years in the area of human factors engineering. He has authored scientific and technical publications dealing with topics as diverse as motion sickness, helmet mounted displays, laser designator systems, simulation, selection and training. He has supported the development and upgrading of a variety of advanced aircraft and systems and taught in the Operations Research Department at the Naval Postgraduate School, the Naval Aviation Safety School, and the Navy Test Pilot School. He is a founding member of the Department of Defense Human Factors Engineering Technical Group for Test and Evaluation and has served in a variety of positions in DOD, national, and international human factors groups. As an Associate Professor of Psychology at the University of Dayton, he continues his research in simulation, workload, cockpit design, displays, and anthropometry. He is presently Chair of both the Test and Evaluation Technical Group and the Accreditation Review Committee of the Human Factors and Ergonomics Society. His E-mail address is: Moroney@udavxb.oca.udayton.edu