System Safety and Engineering

A systems engineering approach to safety starts with the basic assumption that some properties of systems, in this case safety, can only be treated adequately in the context of the social and technical system as a whole. A basic assumption of systems engineering is that optimization of individual components or subsystems will not in 

Approaches used to enhance safety in complex systems must take these basic systems engineering principles into account. Otherwise, our safety engineering approaches will be limited in the types of accidents and systems they can handle. At the same time, approaches that include them, such as those described in this book, have the potential to greatly improve our abihty to engineer safer and more complex systems. 

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To achieve the first two aspects, the system engineer and safety practitioner will need to obtain technical information from the ETSO holder on the behaviour of their component. Whilst software requirements specifications and design descriptions are rarely available (due to intellectual property constraints), the integrator should at least be able to access the technical data on integration and the operator manuals in order to discern the behaviors of the system. Remember though, the focus should not just be the functional behaviors but also the behavior of the system under failure conditions. ... 

While S/W coding is almost entirely the pnrview of the S/W developer, there are several factors that the systems engineer and safety practitioner should be aware of. Specifically, be aware of the factors affecting the introduction of faults during the coding process and how this might impact snbseqnent V V activities. 

Considering the project partners and the project goal by conducting the survey, both systems engineering and safety experience of the partners cover the need to find tools and methods for an early integration of safety methods into model based systems engineering. 

This book is for systems engineering and safety professionals in all disciplines and industries, worldwide. If your knowledge of one discipline is aware of the existence and value of the other, then this book will enhance that awareness. In the event that you are involved in one discipline without knowledge of the other, then this book will help you, from the point of view of another equally important professional discipline, see how a relationship will benefit your organization and industry. If the function you serve is not directly involved with either systems engineering or safety, then I believe that this book will, in a clear and concise way, enlighten you to the value of each discipline and, even more importantly, illustrate the need to build a bridge between the two disciplines. 

As the global economy expands and more advanced technology continues to be utilized worldwide, projects and processes will continue to become more complex. A paradigm will be essential to manage this vast expansion. The bridge must be built between systems engineering and safety and these two separate but very important disciplines must be integrated. Therein lies the purpose of this book. 

Just as in choosing the steps of the life cycle, the models used may be influenced by the incorporation of safety tools. Feedback loops are essential in the life-cycle model, so that issues involving cost, schedule, and safety may be addressed before the project matures beyond the ability of systems engineers and safety professionals to successfully integrate their respective disciplines throughout the management of the project. 

To build the bridge between systems engineering and safety, and of more urgency, to avoid mistakes that have been made when the building of that bridge has not been properly performed (as we see in Chapter 7), the essential elements of management must be understood. This chapter is a brief overview of topics that could individually fill several volumes. I drew upon my years of experience as an engineering professional and the extensive research I conducted for this book to narrow down those elements to Culture, Commitment, Communication, and Coordination—or C . ... 

Just as the incorporation of these elements can contribute to a program that successfully integrates systems engineering and safety, the exclusion of any element at any point in the life cycle may result in a breakdown, where management will overlook safety, even in the face of overwhelming evidence that should have escalated the level of concern. I call this breakdown The Glismann Effect, to be discussed in Section 6.6. 

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