Study planning, HAZOP

Planning the Study. Planning HAZOPs is an important task, and complicated by the following factors ... 

Consider how a safety case regime would have prevented this accident. The standard hazard identification procedure in the industry is a HAZOP (hazard and operability study). Two other gas plants at the Longford site had been HAZOPed but a planned HAZOP of the plant where the... 

Control actions, e.g., provide alarms to indicate things getting out of control define control actions to get back into control. The HAZOP study is not complete until response to actions has been documented. Initial HAZOP planning should establish the management follow-up procedure that will be used. 

Hazard and Operability Analysis (Hazop) (Kletz, 1992) is one of the most used safety analysis methods in the process industry. It is one of the simplest approaches to hazard identification. Hazop involves a vessel to vessel and a pipe to pipe review of a plant. For each vessel and pipe the possible disturbances and their potential consequences are identified. Hazop is based on guide words such as no, more, less, reverse, other than, which should be asked for every pipe and vessel (Table 1). The intention of the quide words is to stimulate the imagination, and the method relies very much on the expertise of the persons performing the analysis. The idea behind the questions is that any disturbance in a chemical plant can be described in terms of physical state variables. Hazop can be used in different stages of process design but in restricted mode. A complete Hazop study requires final process plannings with flow sheets and PID s. 

Also indices such as the Dow Fire and Explosion Hazard Index and the Mond Index have been suggested to measure the degree of inherent SHE of a process. Rushton et al. (1994) pointed out that these indices can be used for the assessment of existing plants or at the detailed design stages. They require detailed plant specifications such as the plot plan, equipment sizes, material inventories and flows. Checklists, interaction matrices, Hazop and other hazard identification tools are also usable for the evaluation, because all hazards must be identified and their potential consequences must be understood. E.g. Hazop can be used in different stages of process design but in restricted mode. A complete Hazop-study requires final process plans with flow sheets and PIDs. 

Hazard and risk analysis is a vast subject by itself and is extensively covered in the literature [22]. In order to plan to avoid accidental hazards, the hazard potential must be evaluated. Many new methods and techniques have been developed to assess and evaluate potential hazards, employing chemical technology and reliability engineering. These can be deduced from Fault Tree Analysis or Failure Mode Analysis [23], In these techniques, the plant and process hazard potentials are foreseen and rectified as far as possible. Some techniques such as Hazards and operability (HAZOP) studies and Hazard Analysis (HAZAN) have recently been developed to deal with the assessment of hazard potentials [24]. It must be borne in mind that HAZOP and HAZAN studies should be properly viewed not as ends in themselves but as valuable contributors to the overall task of risk management... 

The approach to identifying hazards and operability problems by this technique is to search for deviations from design intents. The first step is to plan the HAZOP study to ensure that there is sufficient time, expertise, and information available. Next, a multidisciplinary team, led by an expert in the technique, is set up. Then, by means of a fixed set of abstract words called guide words (such as more ), the team leader examines each process... 

HAZOP is the acronym for HAZard and OPerability study. The method is a structured and systematic examination of a planned or existing product, process, procedure or system. It is a technique to identify risks to people, equipment, environment and/or organisational objectives. The technique was originally developed by ICI as a means of managing risk in industrial chanical plants. 

As mentioned above an EIA may be prepared in the case of accidents. This requires preparation of an operational hazards (HAZOP) study, which indicates the emissions during the accident. Obviously the concentrations of the chemical substances in this case would greatly exceed allowable levels inside the factory site and outside the fences. The duration of this exposure would have an impact on the environment and health of the local population. This case requires preparation of special plans, e.g., contingency plans. Because modem... 

Obviously plan preparation is financed from the budget, but the crucial information required to develop such a plan is included in the preparation of the HAZOP and El A studies. This may be a case whereby enterprises may use state financial resources to improve the environmental situation in everyday and emergency cases. 

Once the detailed plans have been prepared, a more detailed safety analysis can be carried out which could be in the form of a Hazard and Operability Study (HAZOP). ... 

What is HAZOP A HAZOP study is a structured and systematic investigation of a planned or existing plant or operation to identify and evaluate hazards that may... 

As HAZOP study changes with the stage of the project as shown in Fig. lV/1.1.3-1, during planning this needs to be taken into consideration. 

This study is a structured and systematic examination of a planned or existing process or operation in order to identify and evaluate problems that may represent risks to personnel or equipment, or prevent efficient operation. The HAZOP technique was initially developed to analyze chemical process systems, but has been extended to other types of systems and complex operations. A HAZOP is a qualitative technique based on guide words and is carried out by a multidisciplinary team (HAZOP team) during a set of meetings (Model 7.2). 

A HAZOP study is a study carried out on planned or existing plants in an effort to identify operability and safety hazards. 

Hazard and operability studies (HAZOP) HAZOP is a structured and systematic examination of a planned or existing product, procedure or system (lEC/ISO 31010, 2009). The aim is to identify failure modes and their causes and consequences bearing the whole system in mind (lEC/ ISO 31010, 2009, Dunjo et al., 2010). 

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