Prevention of Accidents and Unwanted Occurrences

Theory, Methods, and Tools in Safety Management, Second Edition

Urban Kjellen, Eirik Albrechtsen

• Publisher: CRC Press
• Year: 2017
• ISBN:
  9781351647298
• Edition: 2
• Topic: Business
• Subtopic: Gestione
• Index: Business

This new edition comes after about 15 years of development in the field of safety science and practice. The book addresses the question of how to improve risk assessments, investigations, and organizational learning inside companies in order to prevent unwanted occurrences. The book helps the reader in analyzing the subject from different scientific perspectives to demonstrate how they contribute to an overall understanding. It also gives a comprehensive overview of different methods and tools for use in safety practice and helps the reader in analyzing their scope, merits, and shortcomings. The book raises a number of critical issues to be addressed in the improvement process.

section two

Theoretical foundation

This part lays the theoretical foundation for the presentation of various safety management methods and tools that will be discussed in Sections III through V. Chapter 4 gives a presentation of different accident theories and models. Initially, we will focus on accident models that are necessary in order to ask the right questions in an accident investigation. At the end of the chapter, we will highlight some important aspects related to safety culture, an important dimension that is complementary to the more structural approach used in health, safety, and environment (HSE) management. Chapter 5 summarises many important aspects of the understandings of accidents presented in Chapter 4 within an accident analysis framework. We use this framework when we analyse the different types of information about accident risks used in the management of these risks. Chapter 6 summarises the basic statistical theory of the Poisson process. This theory is applied in Section IV on the monitoring of safety performance. Chapter 7 reviews some basic principles for experience feedback. We will introduce two important concepts – feedback control and diagnosis. We will also discuss some important obstacles to efficient learning from experience. Chapter 8 presents a set of criteria for the evaluation of methods in the management of safety based on the concepts of feedback control and diagnosis. Chapter 9 introduces the concept of safety barriers. It also presents applications of this philosophy in the prevention of ordinary occupational accidents as well as major accidents. Chapter 10 concludes Section II by introducing us to the important area of the role of the human element in accident prevention and human errors.

chapter four

Accident theory and models

The main purpose of this chapter is to lay the theoretical foundation for the analytic framework presented in Chapter 5. This framework will be used as a main building block in our presentation of safety management methods and tools in subsequent chapters. The main focus will be on accident models (i.e. simplified representations of the processes in the real world that result in accidental loss). Many of these models include portions that are substantially theoretical and reflect prevailing theories of accident causation. For our purposes, accident theory means a supposition or system of general principles and ideas intended to explain why accidents occur (cf. Oxford University Press 2012).

We end this chapter with a short review of safety culture. This review is not consistently theoretical. We make some selections by focussing on models of safety culture that explain an organisation’s informal processes and beliefs and how they affect the risk of accidents.

4.1On the need for accident models

Accident models play a vital role in the design of methods for accident investigation and of feedback systems for safety management in general. Each accident model has its own characteristics as to the types of ‘causal factors’ that it highlights. In an accident investigation, for example, accident models support the investigators by:

• Creating a mental picture of the accident sequence
• Asking the ‘right’ questions and defining the types of data to collect
• Establishing stop rules (i.e. rules for when to terminate the search for new causes further away from the accidental event)
• Checking that all relevant data have been collected
• Evaluating, structuring, and summarising the data into meaningful information
• Analysing relations among pieces of information and seeing interrelations
• Identifying and assessing remedial actions
• Communication among people by providing a common frame of reference

The models are also important in risk assessments by supporting in the identification of hazards, deviations and contributing factors that can lead to accidents.

An important aim of introducing an accident model is to establish a shared understanding within the organisation of how and why accidents happen. It is especially important that those parts of the organisation responsible for the collection of information on accident risks and those responsible for using the information in decision-making use a similar frame of reference. Accident models will thus have a direct influence on safety practices, both consciously and unconsciously.

Old accident ‘models’ or perceptions explained accidents as a result of fate (Hovden and Larsson 1987). Accident research during the early part of last century studied the relation between accidents and personal traits of the victim. ‘Accident-proneness’ was a commonly accepted theory at that time (McKennan 1983). It stated that, due to their personal traits, certain individuals are more susceptible to accidents than others. It follows from this theory that accident risk may be reduced substantially by removing ‘accident-prone’ persons from hazardous jobs. Today, ‘accident-proneness’ is considered responsible for only a number of accident incidents. It follows that, in most cases, a preventive strategy based on this theory will have only minor effects. It is relevant, however, for specific types of jobs (e.g. pilots) that involve high mental and/or physical demands and where an error may have a significant safety impact. We do not find accident models that focus solely on personal factors in use in industry today.

The first model considering accidents and their context in a systematic way was established in the 1930s. The so-called domino theory in particular has significantly contributed to current theories and practices in safety management. There are several subsequent models that focus on the sequence of causes in a way that is similar to the domino theory.

Since the 1960s, the field of quality management has been an important contributor to the development of safety management as it is practised today. This contribution has resulted in accident models that emphasise processes and deviations; these are known as process models.

Energy transfer is another important aspect for understanding accidents. The energy model is based on injury epidemiology. It explains an injury as resulting from an energy transfer to the victim’s body in excess of the ‘body injury threshold’ (Gibson 1961; Haddon 1968).

Over the years, accident models also have incorporated and highlighted factors pertaining to management, organisation, and the individual. This has resulted in system models that highlight different parts of the organisational context of accidents (Khanzode et al. 2012).

In the subsequent sections, we present a selection of accident models from the research literature that are relevant to the design of methods applied in safety management. This presentation will help us understand the framework for accident analysis in Chapter 5 and will form the basis for our presentation of safety management methods and tools in Sections III through V of this volume. The intentions of Chapters 4 and 5 are twofold. One is to help the reader develop an understanding of the nature of accidents. The second is to build a pedagogic structure to organise the distinct characteristics of the different methods and tools. We will also include models of historical significance to help the reader understand developments in the general understanding of accident phenomenon.

There are many different models presented in the research literature, representing the needs of individual re...

Table of contents

• Title Page
• Copyright Page
• Table of Contents
• Preface
• Acknowledgements
• Authors
• Section I: Introduction
• Section II: Theoretical foundation
• Section III: Learning from incidents and deviations
• Section IV: Monitoring of safety performance
• Section V: Risk assessment
• Section VI: Putting the pieces together
• Appendix A: Definitions
• Appendix B: SMORT checklists and questionnaire
• Bibliography
• Index