Handbook of Safety Principles

Niklas Möller, Sven Ove Hansson, Jan-Erik Holmberg, Carl Rollenhagen, Niklas Möller, Sven Ove Hansson, Jan-Erik Holmberg, Carl Rollenhagen

• Publisher: Wiley
• Year: 2018
• Print ISBN: 9781118950692
• eBook ISBN: 9781118950715
• Edition: 1
• Topic: Business
• Subtopic: Operations
• Index: Business

Presents recent breakthroughs in the theory, methods, and applications of safety and risk analysis for safety engineers, risk analysts, and policy makers

Safety principles are paramount to addressing structured handling of safety concerns in all technological systems. This handbook captures and discusses the multitude of safety principles in a practical and applicable manner. It is organized by five overarching categories of safety principles: Safety Reserves; Information and Control; Demonstrability; Optimization; and Organizational Principles and Practices. With a focus on the structured treatment of a large number of safety principles relevant to all related fields, each chapter defines the principle in question and discusses its application as well as how it relates to other principles and terms. This treatment includes the history, the underlying theory, and the limitations and criticism of the principle. Several chapters also problematize and critically discuss the very concept of a safety principle. The book treats issues such as: What are safety principles and what roles do they have? What kinds of safety principles are there? When, if ever, should rules and principles be disobeyed? How do safety principles relate to the law; what is the status of principles in different domains? The book also features:

• Insights from leading international experts on safety and reliability

• Real-world applications and case studies including systems usability, verification and validation, human reliability, and safety barriers

• Different taxonomies for how safety principles are categorized

• Breakthroughs in safety and risk science that can significantly change, improve, and inform important practical decisions

• A structured treatment of safety principles relevant to numerous disciplines and application areas in industry and other sectors of society

• Comprehensive and practical coverage of the multitude of safety principles including maintenance optimization, substitution, safety automation, risk communication, precautionary approaches, non-quantitative safety analysis, safety culture, and many others

The Handbook of Safety Principles is an ideal reference and resource for professionals engaged in risk and safety analysis and research. This book is also appropriate as a graduate and PhD-level textbook for courses in risk and safety analysis, reliability, safety engineering, and risk management offered within mathematics, operations research, and engineering departments.

NIKLAS MÖLLER, PhD, is Associate Professor at the Royal Institute of Technology in Sweden. The author of approximately 20 international journal articles, Dr. Möller's research interests include the philosophy of risk, metaethics, philosophy of science, and epistemology.

SVEN OVE HANSSON, PhD, is Professor of Philosophy at the Royal Institute of Technology. He has authored over 300 articles in international journals and is a member of the Royal Swedish Academy of Engineering Sciences. Dr. Hansson is also a Topical Editor for the Wiley Encyclopedia of Operations Research and Management Science.

JAN-ERIK HOLMBERG, PhD, is Senior Consultant at Risk Pilot AB and Adjunct Professor of Probabilistic Riskand Safety Analysis at the Royal Institute of Technology. Dr. Holmberg received his PhD in Applied Mathematics from Helsinki University of Technology in 1997.

CARL ROLLENHAGEN, PhD, is Adjunct Professor of Risk and Safety at the Royal Institute of Technology. Dr. Rollenhagen has performed extensive research in the field of human factors and MTO (Man, Technology, and Organization) with a specific emphasis on safety culture and climate, event investigation methods, and organizational safety assessment.

1
Introduction

Niklas Möller, Sven Ove Hansson, Jan-Erik Holmberg, and Carl Rollenhagen

Principles for action have a much more important role in safety engineering and safety management than in most other disciplines. In practical safety work, we refer to principles such as fail-safe, safety barriers, safety factors, system redundancy, resilience, inherent safety, and many others. Much of the academic literature on safety, safety standards, and regulations recommends the use of one or other such principle. Many of the best-known contributors to the safety literature owe their fame to their roles as originators or promoters of one or other safety principle.

1.1 Competition, Overlap, and Conflicts

But the field is not characterized by consensus on which safety principles we should use. To the contrary, the literature on these principles abounds with divergent and sometimes conflicting recommendations. The overall picture is a rather confused one, due to competition, overlap, and conflicts among the principles.

It is not uncommon to hear presentations in which one of the safety principles is expanded to include all aspects of risk and safety enhancement so that it becomes the overarching principle under which the others can be subsumed. Quite a few of the principles have been presented with such ambitions—general quality principles, integrated risk management, and safety culture to name just a few—but obviously at most one of the principles can be superordinate to all the others. There seems to be a certain element of modishness in the coming and going of safety principles, and the field may not be entirely devoid of factionalism.

More often than not, one and the same safety measure can be presented as based on various principles. Terminologies also differ between industry branches and engineering specialties. For instance, what is called “inherent safety” in the chemical industry is called “substitution principle” in many industries that use chemical products, “passive safety” in the nuclear industry, and “primary prevention” in health-related applications. These principles seem to be close in meaning, but how large is the overlap? Can they perhaps even be described as one and the same principle but under different names?

Conflicts between the principles are far from uncommon. The principle of cost–benefit optimization tells us not to reduce low radiation doses if the reduction is costly, but at least some interpretations of the ALARA (“as low as reasonably achievable”) principle tell us to reduce them. The principle of multiple safety barriers sometimes recommends an extra layer of safety that the principle of simplicity would dissuade us from since it makes the system more complex and difficult to manage in a safety-critical situation. Sometimes, even two applications of the same safety principle can lead to a conflict. For instance, the substitution principle recommends that we replace flammable substances by less flammable ones and toxic substances by less toxic ones. In the choice between two substances, one of which is less flammable and the other less toxic, this will lead to a conflict.

1.2 A New Level in the Study of Safety Principles

As we see it, the study of safety principles has to be taken to a new and more comprehensive level. It is not sufficient to study the principles one at a time, and promotion of single principles needs to be replaced by unbiased comparative investigations. There is no lack of topics for such studies. We need to find out the relationships between the different principles, not least how they overlap and how they may run into conflict with each other. We also need to learn how they are conceived and applied by those who are supposed to be helped by them in their daily work (not only how they are conceived by their most fervent champions). And most importantly, we need to know if they make a difference in practice. What effects, if any, does their application have on safety outcomes? In short, the academic literature on safety principles should become much less advocacy-based and much more evidence-based.

We see this book as a first step toward that new level in the study of safety principles. Most of the major safety principles are presented, and they are all dealt with on an equal basis. We have asked the authors to compare the principle(s) they present to other safety principles. We have also asked them to clarify the limitations and weaknesses of the various principles, and to inform the reader of whatever empirical evidence there may be of the effects of using the principles in practice. The book contains a significant amount of comparative material, and we hope that it will also serve as an inspiration for more comparative studies of safety principles in the near future.

1.3 Metaprinciples of Safety

Does it make any difference which safety principle(s) we appeal to, and which of them we choose as an overarching principle for safety management? We believe that it can indeed make a difference. The reason for this is that the different safety principles put emphasis on different components of safety management. There are many possible “metaprinciples” which may be used for bringing out differences in emphasis between safety principles. We have found the following simple list of basic tasks in safety management useful, and will in this section illustrate how it brings forward an interesting pattern for the principles of safety covered in this handbook:

1. Inventorize. Identify and assess specific safety problems in planned or existing systems.
2. Capacitate. Investigate what capacities the system has to deal with safety-related problems and how those capacities can be improved. Many of these principles are applied in the design phase but can also be implemented as a consequence of applying problem-finding principles in existing systems.
3. Prioritize. Set priorities among the potential improvements.
4. Integrate. Make safety management coherent and comprehensive, for example, by using general quality principles and integrated safety management principles.

Each of these tasks is an important component in safety management. Therefore, the safety principle(s) applied in safety management should sustain the performance of each of them. We will call them metaprinciples since they will be used to evaluate many of the common safety principles.

In Figure 1.1, we have placed three of the safety metaprinciples at the vertices of a triangle, and we have introduced some well-known safety principles at different places in the triangle. The diagram illustrates how these three principles give rise to different approaches to practical safety work. Notably, some safety principles are close to one of the vertices. Such a safety principle will in practice only support one of the metaprinciples, and it is therefore in obvious need of supplementation. One example is the principle of experience feedback. This is a principle with a strong focus on inventorizing. By studying previous accidents, incidents, and other events, we can learn much on how to avoid similar events in the future. But obviously, this does not necessarily teach us about the capacity of the system to deal with the events (particularly unforeseen ones), and neither does it tell us much about how to prioritize among different problems in need of solution.¹ Therefore, the principle of experience feedback is not sufficient to guide safety management as a whole. We will have to add other principles that provide guidance for capacitation and prioritization.

Figure 1.1 Four metaprinciples of safety. Specific safety principles can be characterized according to whether they have a dominant focus on finding real or potential safety problems (inventorize), providing capacity and resources to cope with real or potential problems (capacitate), or to make priorities (prioritize). At the center of the figure are principles that describe how to integrate components of the other principles.

Similarly, the principle of cost–benefit optimization is very close to the vertex representing prioritization. It is a rather complete (but of course not uncontestable) principle for priority-setting of safety measures, but it does not help us much in identifying safety problems or pinpointing general capacity improvements that can increase our preparedness for unidentified hazards. Therefore, cost–benefit optimization is not suitable as an overarching principle to cover all safety work.

In the middle triangle of Figure 1.1, we have positioned safety principles that are very general and usually contain parts of the other three metaprinciples. These principles often give general advice about how to structure safety management and the other metaprinciples. For example, general quality principles give advice that can be applied to most other specific safety principles. Integrated safety management principles are also of this type.

Not surprisingly, principles that are close to each other in the diagram are more likely to overlap than principles at larger distance from each other. For instance, inherent safety and the substitution principle are close to each other in the diagram. This is because they both provide means to avoid both known and unknown dangers. These two principles tend to yield the same recommendations. For instance, both tell us to replace a flammable substance by a non-flammable one, which is an advantage both in known and unknown accident scenarios. The two principles are quite...

Table of contents

• Cover
• Operations Research and Management Science
• Title Page
• Copyright
• Preface
• List of Contributors
• 1: Introduction
• 2: Preview
• Part I: Safety Reserves
• Part II: Information and Control
• Part III: Demonstrability
• Part IV: Optimization
• Part V: Organizational Principles and Practices
• Index
• EULA