Topic: What’s New?

Is this the same as SRA, LSD?

This recommended pipeline risk assessment methodology is similar to SRA (Structural Reliability Analyses) and LSD (Limit State Design) or LRFD (Load and Resistance Factor Design).  This is coincidental, since the methodology was developed independently from these techniques.  However, despite the similarities, there are key differences. Similarities include: Focus on engineering principles rather than incident history Accommodates […]

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 […]

PL Risk Management—The Essential Elements of Risk Assessment

As the desire for more robust pipeline risk management grows, so too does the need for superior risk assessment.  A formal risk assessment provides the structure to increase understanding, reduce subjectivity, and ensure that important considerations are not overlooked.  Associated decision-making is therefore more consistent and reliable when formal techniques are used. But has pipeline […]

What’s behind the EE guideline document that DNV and you recently released?

We are advocating a degree of standardisation that serves all stakeholders. This list of essential elements sets forth the minimum ingredients for acceptable pipeline risk assessment. Every RA should have these elements. A specific methodology and detailed processes are intentionally not essential elements, so there is room for creativity and customised solutions. DNV’s recognition of […]

So are there are now pipeline RA approaches that are both better and cheaper than past practice?

Yes. RA that follows the Essential Elements* (EE) guidelines avoids the pitfalls that befall many current practices. Yet, we can still apply all of the data that was collected for the previous approaches. Pitfall avoidance, full transparency, and re-use of data makes the approach more efficient than other practices. Plus, the recommended approaches now generate […]

Are you advocating exclusively a quantitative or probabilistic RA?

Terminology has been getting in the way of understanding in the field of RA. Terms like quantitative, semi-quantitative, qualitative, probabilistic, etc. mean different things to different people. I do believe that for a true understanding of risk and for the vast majority of regulatory, legal, and technical uses of pipeline RAs, numerical risk estimates in […]

Why do we need more robust results? Why not just use scores?

Even though they were developed to help simplify an analysis, scoring and indexing systems add an unnecessary level of complexity and obscurity to a risk assessment. Numerical estimates of risk – a measure of some consequence over time and space, like ‘failures per mile-year’ – are the most meaningful measures of risk we can create. […]

What are the newest pipeline RA methodologies like?

They are powerful, intuitive, easy to set up, less costly, and vastly more informative than either of the previous approaches. By independent examination of key aspects of risk and the use of verifiable measurement units, the whole landscape of the risks becomes apparent. That leads to much improved decision making.

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 […]