The following sections are included: background to HFI prior to the mid 1980s; post mid 1980s; scope of application of HFI; life cycle management and risk; starting an HFI programme; early human factors analyses; the future; conclusions; and references.

In theory, all the objects in the built world should have been carefully designed for the human user. In practice, this is not the case and we are surrounded by poor design. Certainly, in the past in industry, poor design was not considered a priority. Ergonomics derives from the word 'erg' meaning work, and 'nomos' meaning science; hence, it is the study of the science of work. The terms ergonomics and human factors are often taken as synonymous, although there is some evidence that ergonomics has its origins more in the consideration of the physiological aspects of the human, while human factors focuses more on the psychological element. In summary, human factors (or ergonomics) is all about design. But there is little point in designing something for humans to use without carrying out some form of assessment that this objective has actually been met. Consideration of how to assess and evaluate design provides the focus of the current chapter, namely, an overview of the methods, grouped together under the umbrella of the human factors toolkit, which can be employed for assessing the design of products and systems.

The word automation, which comes from Greek, is a combination of auto, 'self, and matos, 'willing', and means something that acts by itself or of itself. This is almost identical to the modern usage where automatic means something that is self regulating or something that acts or operates in a manner determined by external influences or conditions but which is essentially independent of external control, such as an automatic light switch.

This document has provided an overview of a framework for the assessment of human error in risk assessments. The main emphasis has been on the importance of a systematic approach to the qualitative modelling of human error. This leads to the identification and possible reduction of the human sources of risk. This process is of considerable value in its own right, and does not necessarily have to be accompanied by the quantification of error probabilities. Because of the engineering requirement to provide numerical estimates of human error probabilities in applications such as safety cases, examples of major quantification techniques have been provided, together with case studies illustrating their application. It must be recognised that quantification remains a difficult area, mainly because of the limitations of data. However, the availability of a systematic frame work within which to perform the human reliability assessment means that despite data limitations, a comprehensive treatment of human reliability can still yield considerable benefits in identifying, assessing and ultimately minimising human sources of risk.

The purpose of this chapter is to delineate the many facets of developing interfaces in order to provide fruitful design directions for practitioners to take in the area. To this end, the chapter is divided into four distinct sections. The first, Section 10.2, provides a brief history of interface design along with defining its scope and why it is important, especially in light of the continual problems in usefulness and ease of use of many interfaces that are designed today. Based on this understanding, Section 10.3 categorises the area according to the broad treat ment of three key topic areas in interface design, covering human factors issues (see Chapter 1 for formal definitions), interface types and design principles that are important considerations in the development of interfaces. Practical applica tions of the knowledge gained from the discussions thus far will be demonstrated in Section 10.4, through two interface design cases. These cases are analysed with consideration to the issues drawn out from previous sections, thus spotlight ing the various pitfalls and benefits to design. Section 10.5 concludes the chapter with a final reflection on the nature and inherent difficulties in producing effective interfaces.

This chapter will give guidance on how to assist the performance of system verification and validation (V&V) through the application of human factors (HF) to design during the various phases of a system's life cycle. Notably, a system will be considered as consisting of both humans and machines operating within social, cultural and operating environments. Figure 12.1 depicts this problem space and suggests that HF should be central to the consideration of systems. Therefore, the importance of empathy by the HF practitioner to the activities of the system engineer/maintainer and the user/operator should be emphasised. Moreover, it is argued that true expertise in HF is only acquired through a polymathical approach to work and an understanding of the approaches to the challenges of a system's life cycle by other disciplines such as systems engineering and integrated logistics support.

This chapter examines the safety assessment of systems that include people. Specifically, the chapter is concerned with the analysis of safety in complex, information systems that characteristically support dynamic processes involving large numbers of hardware, software and human elements interacting in many different ways. The chapter assumes little or no knowledge of either safety assessment or human factors assessment techniques. Information systems involving extensive human interactions are increasingly being integrated into complicated social and organisational environments where their correct design and operation are essential in order to preserve the safety of the general public and the operators. This chapter focuses on the safety assessment of information systems, typically operating in real time, within safety-related application domains where human error is often cited as a major contributing factor, or even the direct cause, of accidents or incidents.