Quantitative Risk Analysis Techniques Part 3 – Risk Results and Risk Mitigation

In the first part of quantitative risk analysis techniques, we learnt about crucial step of the analysis which are hazard identification and cause and frequency analysis. In second part, we learnt continuation of the first part, which are fault tree analysis or event tree analysis as an approach to estimate frequency. After that we learnt about consequence modeling and several potential consequences.

In this post we will learn about risk results and risk reduction and mitigation.

Risk Results

There are two graphic forms that are usually used to present risk result: individual risk contours and societal risk F-N curves (Frequency-Number of fatalities).

Individual risk is the risk to a person in the vicinity of a hazard. This includes nature of the injury to the individual, likelihood of injury occurring, and time period of injury occur.

Societal risk is a measure of risk to a group of people. It is mostly expressed as frequency distribution of multiple casualty events. Read More

Quantitative Risk Analysis Techniques Part 2

In previous post, quantitative risk analysis techniques is started with hazard identification then frequency analysis. Frequency itself can be estimated by two approaches, which are generic data approach and modeling approach. The first approach is already described in previous post.

Modeling approach is used to estimate leak frequency when general statistics data is not available. Modeling approach use fault tree analysis or event tree analysis

Fault Tree Analysis (FTA)

Fault Tree Analysis provide estimated frequency/likelihood of even for events that have never occurred by combining all possible basic failure mode (collision, dropped object, human error). These modes are combined and we tract how these initiating events can propagate to the top event by progressive failures of safeguard or by combining with other events. We use AND or OR gate. Read More

Quantitative Risk Analysis Techniques Part 1

Last time I involved in quantitative risk analysis (QRA) project in LNG regasification facility as supporting process engineer. Actually, I did not involve in QRA project itself, but I involved in back pressure study. In order to get to know about this field, I want to share you some basics quantitative risk analysis techniques as mentioned in several literatures, such as BS EN standards and AiChE publications.

Quantitative Risk Analysis is a procedure to accommodate management with event scenarios, measure of likelihood, and magnitute of potential losses. After risk analysis, we want to manage the risk by several means.

• Reduce the frequency of accidents
• Reduce the consequence of accidents
• Provide insurance