The Pathway to ASME PCC-1 2013 Appendix A Compliance and its Critical Importance

In November 2013, the American Society of Mechanical Engineers (ASME) released its updated PCC-1 guidelines [1] for pressure boundary bolted flange joint assemblies (BFJAs).  Contained within the document is Appendix A, which represents a major change from the previous 2010 release and is considered to be one of the most critically important changes for BFJA technicians, operators, and other industry professionals.  Appendix A contains significant guidance for the levels of training and experience required for technicians working on BFJAs.

In the past, BFJAs were not as highly regulated as welded joints, despite the fact that both types of assemblies carry the same risk and are often securing the same process at the same pressures and temperatures.   In fact, as documented by the Society of Petroleum Engineers in its paper number SPE 164981[2], about 60% of leaks have been associated with manual human intervention in process systems.  The most common activities involved with associated leaks include:

• Incorrect fitting of flanges, gaskets or bolts during maintenance
• Valves in incorrect position after maintenance
• Breakdown of the isolation system during maintenance

The paper goes on to state that a major contributing factor can be explained by a lack of competence of personnel involved in such activities.  This conclusion is supported by a recent joint study by the Norwegian University of Stavanger and the Norwegian Oil and Gas Association[3].  According to the study, the Norwegian oil and gas industry realized that the prevention of hydrocarbon leaks is of great importance because they are the most critical precursor event that can lead to major accidents.  Yet, careful analyses and new training, methods, and personnel competency can greatly reduce the number of leaks in oil and gas installations.

Specifically, the study states that the number of hydrocarbon leaks on offshore installations on the Norwegian continental shelf peaked just after the year 2000, when more than 40 leaks per year of an initial rate greater than 0.1 kg/s were found.  In response, the Norwegian Oil and Gas Association conducted a training and reduction project from 2003 through 2008, which resulted in only 10 hydrocarbon leaks greater than 0.1 kg/s in 2007.  Also, in 2011, the same association began a new project to further reduce leaks, which has shown promising results.  So far, the study has shown that more than 50% of leaks are associated with the failure of operational barriers during human intervention in process systems.  The single operational barrier that has failed most often is the verification of critical activities.