Topic: Risk Assessment Methodologies

Pipeline Risk Assessment

Risk assessment on any facility is most efficiently done by first dividing the facility into components with unchanging risk characteristics. For a cross-country pipeline, this involves collecting data on all portions of the pipeline and its surroundings and then using this data to ‘dynamically segment’ the pipeline into segments of varying length. Risk algorithms are […]

Damage vs failure: a risk assessment needs to know the difference

To measure resistance in a way most useful to a risk assessment, we must estimate the possible presence of weaknesses, the rate of emergence of future weaknesses, and the role of each weakness in strength reduction. By W. Kent Muhlbauer, WKM Consulting, Austin, TX, USA Since several of our recent columns have dealt with management-of-risk […]

Measuring Failure Potential—What is Attacking? 

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 […]

Pipeline Risk Assessment: Threat Interaction—A Case of Confusing Terminology

As we continue this exploration of pipeline risk assessment, let’s tackle some terminology obstacles.  Pipeline risk assessment is a challenging topic on its own, so added confusion from terminology is most unwelcome. Background In some recent regulatory initiatives, a criticism has arisen regarding some pipeline operators’ failure to properly account for ‘threat interaction’ in their […]

The PHMSA has recently criticised how Integrity Management Plan (IMP) risk assessments (RAs) for pipelines are being conducted. Do you also see problems?

There is a wide range of practice among pipeline operators right now. Some RA is admittedly in need of improvement, not yet meeting the intent of the IMP regulation. However, I believe that is not due to lack of good intention, but rather incomplete understanding of risk. Risk is a relatively new concept, and is […]

Intelligent simplifications

The challenge when constructing a risk assessment model is to fully understand the mechanisms at work and then to identify the optimum number of detailed variables for the model’s intended use. This follows the reductionist approach previously discussed—breaking the problem down into pieces for later reassembly into meaningful risk estimates. We must understand and embrace […]

Risk assessment should not add complexity!

In any modeling effort, complexity should exist only because the underlying real-world phenomenon is complex. The risk assessment should not add complexity. Ironically, a scoring type risk assessment, intended to simplify the modeling of real-world phenomena, actually adds complexity. By converting real-world phenomena into ‘points’ via an assignment protocol, an artificial layer of complexity has […]

How to do modern pipeline risk assessment?

Pipeline Risk Management Chapter 1 highlights 1.1 Risk assessment at-a-glance 1.2 Risk: Theory and application 1.2.1 The Need for Formality 1.2.2 Complexity 1.2.3 Intelligent Simplification 1.2.4 Classical QRA versus Physics-based Models 1.2.5 Statistical Modeling 1.3 The Risk Assessment Process 1.3.1 Fix the Obvious 1.3.2 Using this Manual 1.3.3 Quickly getting answers 1.4 Pipeline Risk Assessment: […]