How Effective are Defenses? Can it Survive? In several previous columns, we have noted the need for a very specific approach to measuring failure probability (PoF). Three factors must be independently measured/estimated in order to fully understand PoF. Let’s explore those factors a bit deeper here. Regardless of the definition of ‘failure’ being used, failure […]
Results for Data
Myth Busting—I don’t have enough data (Part 2)
In the first part of this discussion, we hopefully dispelled some myths about low data availability. We discussed how reasoning is used to generate data and how many useful pieces of risk insight emerge from even simple pieces of knowledge. We also contrasted a statistical approach to risk assessment with a physics based approach. The […]
Pipeline Risk Assessment—Myth Busting Part 1
In the first installment of this column, we introduced the concept of pipeline risk assessment Essential Elements. This is a list of ingredients that arguably must be included in any pipeline risk assessment. In this installment, let’s examine “I can’t do good RA because I don’t have enough data.” There are at least two aspects […]
Pipeline Risk Assessment—Controlling the Bias
In the first installment of this column, we introduced the concept of pipeline risk assessment Essential Elements. This is a list of ingredients that arguably must be included in any pipeline risk assessment. Last time, we covered one of these essential elements—the need for measurements. This time, we address another essential element, closely related to […]
How do I include flange and screw-connection leaks that are really just ‘wiggling loose’ over time?
This scenario must first be categorized in terms of its underlying failure mechanism. An underlying question to answer when categorizing a failure mechanism as either time independent or time dependent is ‘if there have been no changes in any forces, then why did it fail today instead of yesterday?’. When a fitting or appurtenance has performed […]