Scenario identification

The first question represents hazard identification. The last three questions are associated with risk assessment, considered in detail in chapter 11. Risk assessment includes a determination of the events that can produce an accident, the probability of those events, and the consequences. The consequences could include human injury or loss of life, damage to the environment, or loss of production and capital equipment. Question 2 is frequently called scenario identification. 

See also Hazard acceptance Hazard assessment Hazard identification entries limitations of, 13 153-154 probability, 13 166-170 purpose of, 13 152 scenario identification, 13 165 source modeling and consequence modeling, 13 165-166 sustainable development and, 24 183-188 techniques for, 13 152-154 Hazard and operability (HAZOP) analysis, 13 154, 157-159 guide words for, 13 158t sample, 13 159... 

Scattering techniques, 23 126-127 Scenario analyses, 24 189-190 Scenario-based approach for reliability, 26 1044 in process scheduling, 26 1042-1043 Scenario identification, 13 165 SCH 58235... 

Scenario identification in oil and gas industry A case in the Middle East... 

First, K., 2010. Scenario identification and evaluation for layers of protection analysis. Journal of Loss Prevention in the Process Industries, 23(6) 705-718. 

As background information for the scenario identification, PSA s RNNP project was used (PSA, 2012). Table 2 outlines the set of hazard and accident situations (Norwegian DFUs) that could lead to severe damage and loss of life in petroleum production. 

Another topic is whether to apply more safety-performance methods during the WS and discussions with the operating company, as supplement to the data-based scenario identification. As commented in the evaluation, the historical data of incidents and events may not reflect the whole risk picture. Positioning failures are less investigated even though they represent major accident potential. Risk based approaches (0ien, 2001) and safety performance based approaches (HSE, 2006, Sklet et al., 2010) could here be a supplement to the barrier and indicator identification. 

The review of historical incidents and events, along with mapping in STEP diagrams gave a good basis for the scenario identification. However, other approaches may also apply to this step as discussed in the previous section. Additionally, the bow-tie method for scenario analysis was valuable in sense of providing fruitful WS discussions. It also provided a good platform for the barrier evaluations and visualization of the main results. 

The detection of a specific gas (10) is accompHshed by comparing the signal of the detector that is constrained to the preselected spectral band pass with a reference detector having all conditions the same except that its preselected spectral band is not affected by the presence of the gas to be detected. Possible interference by other gases must be taken into account. It may be necessary to have multiple channels or spectral discrimination over an extended Spectral region to make identification highly probable. Except for covert surveillance most detection scenarios are highly controlled and identification is not too difficult. 

An important part of hazard analysis and risk assessment is the identification of the scenario, or design basis by which hazards result in accidents. Hazards are constandy present in any chemical faciUty. It is the scenario, or sequence of initiating and propagating events, which makes the hazard result in an accident. Many accidents have been the result of an improper identification of the scenario. 

Most hazard identification procedures have the capabiUty of providing information related to the scenario. This includes the safety review, what-if analysis, hazard and operabiUty studies (HAZOP), failure modes and effects analysis (FMEA), and fault tree analysis. Using these procedures is the best approach to identifying these scenarios. 

The ha2ard assessment is to iaclude identification of a worst-case scenario and other more likely scenarios for release of a regulated substance, and analy2e the off-site consequences of such releases. The release and consequence assessment is to iaclude the rate, duration, and quantity of the release, the distances for exposure or damage (usiag atmospheric, called "F" stabiUty and a 1.5-m/s wiad, and most-often-occurriag conditions), populations that could be exposed, and environmental damage that could be expected. 

The degree of confidence in the final estimation of risk depends on variability, uncertainty, and assumptions identified in all previous steps. The nature of the information available for risk characterization and the associated uncertainties can vary widely, and no single approach is suitable for all hazard and exposure scenarios. In cases in which risk characterization is concluded before human exposure occurs, for example, with food additives that require prior approval, both hazard identification and hazard characterization are largely dependent on animal experiments. And exposure is a theoretical estimate based on predicted uses or residue levels. In contrast, in cases of prior human exposure, hazard identification and hazard characterization may be based on studies in humans and exposure assessment can be based on real-life, actual intake measurements. The influence of estimates and assumptions can be evaluated by using sensitivity and uncertainty analyses. - Risk assessment procedures differ in a range of possible options from relatively unso-... 

Figure 7.3 Identification of significant issues within GWP and HTP, Vbatch = 60%, Vconti = 88%, FU = 10 kg /7 -anisaldehyde, four scenarios regarding the lifetime of the micro-structured devices (Conti wc 1 week, Conti Scl 3 months, Conti Sc2 3 years, Conti Sc3 10 years).

One of the most important elements of the PSM Rule is the process hazard analysis (PrHA). It requires the systematic identification of hazards and related accident scenarios. The PSM Rule allows the use of different analysis methods, but the selected method must be based on the process being analyzed. The PSM Rule specifies that PrHAs must be completed as soon as possible within a 5-year period. However, one-fourth of the PrHAs must have been completed by May 26, 1994, with an additional one-fourth completed each succeeding year. The highest risk processes were to be done first. A schedule for PrHAs must be established at the outset of a process safety management (PSM) program to give priority to the highest risk processes. PrHAs must be reviewed and updated at least every 5 years. 

For each specific relief all possible scenarios are identified and cataloged. This step of the relief method is extremely important The identification of the actual worst-case scenario frequently has a more significant effect on the relief size than the accuracy of relief sizing calculations. 

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... 

Logic Model Methods The following tools are most commonly used in quantitative risk analysis, but can also be useful qualitatively to understand the combinations of events which can cause an accident. The logic models can also be useful in understanding how protective systems impact various potential accident scenarios. These methods will be thoroughly discussed in the Risk Analysis subsection. Also, hazard identification and evaluation tools discussed in this section are valuable precursors to a quantitative risk analysis (QRA). Generally a QRA quantifies the risk of hazard scenarios which have been identified by using tools such as those discussed above. 

Identification and evaluation of worst case scenarios involving uncontrolled reactivity. 

Key elements of reactive hazard identification are owner-initiated review, chemistry review, review of unit operations, review of scenarios, definition of required testing, records testing, and interpretation of results for owner. 

The science that deals with the identification and quantification of the components of material systems such as these is called analytical science. It is called that because the process of determining the level of any or all components in a material system is called analysis. It can involve both physical and chemical processes. If it involves chemical processes, it is called chemical analysis or, more broadly, analytical chemistry. The sodium in the peanut butter, the nitrate in the water, and the ozone in the air in the above scenarios are the substances that are the objects of analysis. The word for such a substance is analyte, and the word for the material in which the analyte is found is called the matrix of the analyte. 

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