14.1 Introduction

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 often require complex functionality to assist human operators with intricate tasks such as, for example, the conflict detection and resolution systems that assist air traffic controllers with critical decision-making tasks in modern air traffic management. As well as the complexity of modern technology and organisations, humans are also themselves inherently complex and the human factors relating to the physical and cognitive capabilities and limitations of system operators must also be addressed during the assessment of any complex, interactive system.

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.

14.2 Information systems and safety

The safety assessment of modern information systems is a growing concern; for example, command and control (C2) systems are now being developed with the...