Definitions HAZOP study

The primaiy goal in performing a HAZOP study is to identify, not analyze or quantify, the hazards in a process. The end product of a study is a hst of concerns and recommendations for prevention of the problem, not an analysis of the occurrence, frequency, overall effects, and the definite solution. If HAZOP is started too late in a project, it can lose effectiveness because ... 

For example, a traditional checklist is, by definition, based on the process experience the author accumulates from various sources. The checklist is likely to provide incomplete insights into the design, procedural, and operating features necessary for a safe process. The what-if part of the analysis uses a team s creativity and experience to brainstorm potential accident scenarios. However, because the what-if analysis method is usually not as detailed, systematic, or thorough as some of the more regimented approaches (e.g., HAZOP study, FMEA), use of a checklist permits the PrHA team to fill in any gaps in their thought process. 

In the forthcoming Hazop standard (IEC 61882, 1999) the Hazop studies are recommended to be carried out throughout the life cycle of a system. But for the concept and definition phase of a system s life cycle other basic methods are suggested (see Fig. 3). 

Consequence endpoint definition Each scenario addressed in a HAZOP study consists of two basic elements the initiating event (which is the cause that starts the chain of events) and a consequence. Normally, the team assumes active preventive safeguards can fail and examine the consequences through the loss event. The loss event can be defined as the point of time in an incident sequence when an irreversible physical event occurs that has the potential for loss and harm impacts (CCPS, 2008). 

For the purpose of this text, the following definitions are provided for the HAZOP study and the what-if analysis ... 

Definitions (provide essentiai definitions, such as HAZOP study and what-if anaiysis, here)... 

HAZOP study for procedure This is normally a detailed method and should be properly defined. This study is usually carried out by a well-balanced team from different disciplines. The information required includes but is not limited to procedure definitions, up-to-date P IDs, and other relevant drawings and documents. Also the aim of the study (depth of study and major area of interest such as HSE, accident, etc.) needs to be well defined before starting a step-by-step procedure. Each stage/step and action is examined with the guide word to identify meaningful deviation for analysis for hazard identification. In the case of a HAZOP study for procedure, human error is an important factor. 

Provides essential definitions, such as HAZOP Study and What-If Analysis, here METHODOLOGY... 

Independently on how these two methodologies are applied, some aspects of the HAZOP are crucial to guarantee a favorable LOPA study development. The points here addressed, such as the consequence endpoint definition and the HAZOP documentation approach, are those identified with the Petrobras coke drums analysis. 

In addition to updated content of the first edition, the revised second edition of the Basic Guide to System Safety has a more expanded and useful glossary of terms it also contains a new chapter describing the basic concept, utility, and function of the hazard and operability study (HAZOP) and what-if analysis. Both of these analytical techniques have been used quite routinely and successfully in the petrochemical industry for decades. As with all analytical methods and techniques presented in this text, it is suggested that the HAZOP smdy and what-if analysis have definite application to general industry operations as well. 

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