TABLE OF CONTENTS In Chapter 1, we have outlined the difference between hazard and risk. Hazard is not equal to risk and this distinction is critical.
If we focus only on risk analysis, without identifying the underlying causes of the hazards, the questions asked are: "What can go wrong?", "How big?", "How often?" and "So what?" (Kletz 1999). The hazard identification for this level is concerned with the inherent hazard of the material stored or processed, and protection measures in place to prevent a loss of containment. The risk analysis often starts with a loss of containment event (what can go wrong), uses consequence models to estimate severity (how big), uses generic reliability databases for estimating a frequency (how often), and calculates the risk (so what).
In the above approach, the underlying causes of process hazards, especially resulting from abnormal situations and deviations from intended operation may not be identified (Johnson 2000). The 'ignorance factor' arises from failing to identify underlying causes of process hazards.
This chapter is devoted to the systematic hazard identification techniques available for detailed identification of process hazards, and the suitability of each technique for the various life cycle stages.
