Hazard identification process description

For example, any sound analysis, including risk analysis, should be based on a series of observations and measurements. The first stage of this activity, before the hazard identification can be carried out, should be to define a system to be analysed, including the definition of the scope and context of the analysis, and the development of some form of system description. This preparation should also support the identification of the experience and expertise of the participants of the hazard identification process. Yet none of the guidelines provide any support in this area. 

Fire and Explosion Index (Ffrom fires and explosions. frequency The rate at which observed or predicted events occur. HAZOP HAZOP stands for hazard and operabihty studies. This is a set of formal hazard identification and ehmination procedures designed to identify hazards to people, process plants, and the environment. See subsequent sections for a more complete description. 

Figure 10-1 illustrates the normal procedure for using hazards identification and risk assessment. After a description of the process is available, the hazards are identified. The various scenarios by which an accident can occur are then determined. This is followed by a concurrent... 

Figure 23-1 shows the hazards identification and risk assessment procedure. The procedure begins with a complete description of the process. This includes detailed PFD and P I diagrams, complete specifications on all equipment, maintenance records, operating procedures, and so forth. A hazard identification procedure is then selected (see Haz-ard Analysis subsection) to identify the hazards and their nature. This is followed by identification of all potential event sequences and potential incidents (scenarios) that can result in loss of control of energy or material. Next is an evaluation of both the consequences and the probability. The consequences are estimated by using source models (to describe the... 

The check list method is based on past experience. The process description, the operating mode, is screened using a list of possible failures or deviations from this particular operating mode. Thus, it is obvious that the quality and comprehensiveness of the check list directly govern its efficiency. Indeed, the experience of the authors confirms that the check list is essential. This method is well adapted to discontinuous processes as practised in the fine chemicals and pharmaceutical industries, where processes are often performed in multi-purpose plants. The basic document for the hazard identification is the process description, also called operating mode. Each step of the process is analysed with the check list. 

Dr. Frank P. Lees, Loss Prevention in the Process Industries Hazard Identification, Assessment and Control, 2d ed., ISBN 0-8169-1547-8. This is a three-volume set published by Butterworth-Heinemann, Oxford. U.K., 1996. Dr. Frank Lees s epic three-volume masterpiece is without a doubt the premier source of practical and statistical pnKess safety reference material. Within the. 1,962 pages of valuable facts, nearly every aspect of process safety is covered. Should you wish additional description of the b(K)k. try Butterworth-Heinemann s web site at www.butterworth.heinemann.co.uk/register/ us/index.htm. Since this is a British text, there is little specific information on compliance with the OSHA Process Safety Management standard. A large index makes it easy to find specific subject material. List price 599, and worth every penny. I have seen discounted prices. 

An example of a mapping from the equipment representation to the thermodynamic state representation is shown in Fig. 5. It represents an isothermal vertical packed-bed catalytic reactor equipped with temperature and pressure sensors, an explosion vent, and a distributor plate. Notice that the equipment and sensors are not associated with the state representation. They are contained in the base representation and reside in the process description at the equipment level. As discussed earlier, flow, work, heat, and mass interactions are all modeled independently. This allows us to evaluate independently the effect of these processes. Independent evaluation assists in the identification, evaluation, and assessment of event pathways leading to hazardous states. 

Contemporary risk management follows a maturing path to the establishment, acceptance and management of a level of risk that is deemed tolerable and as low as reasonably practicable (ALARP). The recent issue of military standards [MoD 2004] describes six processes for risk management hazard identification, hazard analysis, risk estimation, risk and ALARP evaluation, risk reduction and risk acceptance. Whilst these are not the universal descriptions of the processes involved, the underlying principles are consistent with other procedures and handbooks, for example lEC 61 SOS, JSP 4S4 and Mil Stan 882D. 

System Conceptualisation, Representation and Scoping (System Analysis). This stage of the analysis is often omitted from safety literatnre and standards. This preparatoiy phase is necessaiy in order to provide a stmctured framework and systematic approach for the hazard identification, risk assessment, and for snpporting a holistic approach to the analysis. Some form of system description model, for example state transition model or sequence and collaboration diagrams, should be used as the basis for hazard identification, as the hazards resulting from each system interface, process or interaction can be elicited. The novel approach, developed as part of the research, to system conceptualisation in support of safety analysis, is discussed later in the book ... 

As already mentioned in support of further hazard identification, for each Core Hazard a Process Model has been developed and was used to structure the Change Safety Analysis as described earUer. For each interface, the ICSA class is identified and recorded, and a reference to the relevant core hazard is kept as well as the description of the identified cause. All of the identified causes have been mapped to QRA model elements as well. This activity supported later quantification of some of the safety requirements as detailed later in this book. 

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