HAZard and OPerability HAZOP Studies

A HAZOP (Hazard and Operability Study) involves a fonual review of proeess and instrumentation diagrams by a speeialist team using a stmetured teehnique, based upon key words. These eomprise property words and guide words , e.g. as in Table 12.4. 

The HAZOP Study is a very popular predictive method which was developed in the Mond Division of Imperial Chemical Industries during the 1960s. A HAZOP (Hazard and Operability) study is an analysis method for identifying hazards and problems which prevent efficient operation. Trevor Kletz was an early promoter of the HAZOP Method and in one of his recent books [18], he states ... 

As described earlier, a HAZOP hazard and operability study) is a technique used to identify process hazards and obstacles to the efficient operation of industrial facilities. It provides a systematic approach to quantifying hazard potentials. A HAZAN hazard analysis) is a technique for quantitative evaluation after a serious hazard has been identified or after an accident has occurred. 

HAZOP (Hazards and Operability study)— program/activity... 

There are many different methodologies under the Process Hazards Analysis (PHA) umbrella. Depending on the goals of the study and the time available, one of several different studies would be completed. One of the most comprehensive PHAs is a HAZOP (Hazards and Operability Study), which identifies operability problems as well as hazards to personnel, company property, and the environment. 

All employed dryers must be equipped with clear and comprehensive operating manuals prepared jointly by the equipment supplier and the plant operating management. The manual should be learned by the operators, who are to be trained in recognition of hazardous situations and risk assessment with the material being dried. Very useful techniques, known as Hazop (hazard and operability studies) and Kazan (hazard analysis), may be applied successfully in both new and existing processing plants [39,40]. 

XI. Preliminary Process Safety Studies A simple what-if study is generally performed to identify major safety concerns, if any, with the project scope. FMEA (failure modes and effects analysis) or HAZOP (Hazard and operability) study can also be performed if sufficient design documents are available. Otherwise, these detailed studies will be conducted in FEED. Necessary changes are made to the project scope for mitigating any significant process safety concerns. 

The first set of postulations used a series of guide words, similar to that used in HAZOPs (HAZard and OPerability studies (Lees F. P. 2005)) in the chemical processing industry, to examine what if situations. 

Rausand, M. 2005. HAZOP Hazard and Operability Study, http //www.ntnu.no/ross/srt/sltdes/hazop.pdf, 1 October. 

This analysis is done early in the design stage, and would be a part of a Hazop (hazard and operability) study. It is the initial step in the system safety analysis, and it considers the total system. 

HAZOP Hazard and Operability Studies — a technique in which a combination of systematic rules and engineers vivid imaginations are applied to proposed designs (or existing processes) to identify hazards... 

HAZOP Hazard and Operability (study)—A structured means of evaluating a... 

Thorough specification, design and design review, construction and cotrunission-ing using techniques such as HAZOP (hazard and operability study) which asks what if questions and FMEA (failure mode and effects analysis) which looks at likely sources of engineering failure and the consequences of it. The what if questions can include ... 

The Gulf of Mexico has between 5000 and 6000 platforms—many of them small and in shallow water. It is simply not economically feasible to write a safety case for each platform. Arnold (2010) uses the example of the response to a proposed requirement from the MMS to carry out a Failure Modes and Effects Analysis (FMEA) on each facility. Instead of doing this, generic FMEAs and HAZOPs (Hazard and Operability Studies) were carried out on 13 facilities. This was done because the process equipment and instrumentation are very similar to one another for these platforms. 

For facilities that are still in the design stage, the actions taken, particularly during the Risk Assessment step, will change for each iteration. For example, early evaluations of risk will use a HAZID (Hazard Identification) technique later on, as detailed engineering information becomes available, the more comprehensive HAZOP (Hazard and Operability Study) method will be used. 

If the operation being considered is a new one involving high loss potential, the use of formal hazard analysis techniques such as HAZOP (Hazard and Operability study), FTA (Fault Tree Analysis) or Failure Modes and Effects Analysis should be considered. 

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