Chapter 31.1: Risk

Chapter 31.1: Risk


The purpose of this chapter is to discuss the meaning of risk in its broader organisational and societal context and the implications this has for managing occupational health and safety (OHS) risks. Risk is a complex concept, but we often try to describe a risk in only a few words and represent its magnitude as a single value. The validity of the assumptions normally made in recording and assessing risks are explored with a quantitative example used to explain some of the problems. The most important part of managing risks in the workplace is not to measure it (qualitatively or quantitatively) but to understand the nature of risks, their causes and consequences and to use this information to control risks. This chapter aims to explore terminology issues, discuss the concept of risk and how risk is assessed then consider how to apply a risk management process in a safety context.

Keywords: Occupational Health and Safety, OHS, risk, uncertainty, likelihood, consequence, risk assessment, risk analysis, level of risk, risk management

First year of publication: 2012

Current Version : 2019

Chapter 31.1: Risk

Table of contents

1 Introduction
1.1 Hazards and Risks
2 Definitions of Risk
2.1 Risk as a description
2.2 Risk as a measure
3 Estimating a level of risk
3.1 Introduction
3.2 The value of consequences
3.3 Issues with defining likelihood
3.4 How consequence and likelihood are combined
3.5 Risks with multiple possible values of consequence
3.6 Risks with multiple types of consequence
3.7 Risks with gradual or time delayed consequences
3.8 Qualitative considerations
4 Risk and decisions
4.1 Defining Acceptable level of risk
5 Implications for practice
5.1 Definitions of risk
5.2 Risk management
5.3 Risk assessment
5.4 Risk Treatment
6 Summary

Professor Jean Cross Bsc PhD FIE Aust MAIRM.FSIA(Hon)
Emeritus Professor Risk and Safety Sciences, University of New South Wales

Professor Cross has a degree and PhD in physics obtained in the UK. She has was involved in research and consulting work in the fields of electrostatics (hazards and applications), dust explosions and air pollution control before taking up an appointment as chair of Safety Engineering at UNSW in 1988 where she taught safety risk management for 20 years. She has also been involved in standards development in the field of risk management and reliability. She was chair of the Australian standards committee that developed AS4360 Risk Management from 1992 until 2004 She retired from UNSW in 2008 but continues with some teaching and with standards work.

Peer reviewers

Dr Keith Adam MBBS, AFOEM
Senior Occupational Physician, Medibank Health Solutions, Queensland

Sally Bennett BSc, GDipChemEng, GDipOHM, MBA, CPMSIA
Director, Enhance Solutions; Sessional Lecturer, Deakin University; President, Victorian Chapter, Risk Management Institute of Australia.

Associate Professor Andrew Morrell Beng, GDipMgt
Minerals Industry Risk Management, Minerals Industry Safety and Health Centre, University of Queensland

Learning Outcomes: Risk

The OHS Body of Knowledge takes a conceptual approach which enables it to be applied in different contexts and frameworks. To optimise its value for education and professional development learning outcomes have been developed for each technical chapter in the Body of Knowledge.

The learning outcomes as described give an indication of what should be the capabilities of a new graduate OHS professional in the workplace. I t is up to those developing OHS education programs, OHS professionals planning their CPD or recruiters or employers selecting or developing people for the OHS function to consider the required breadth vs. depth

Find Out More About Using the OHS BOK Learning Outcomes


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