Part 3: Mechanical Integrity Citations
This is our last installment of our three part series on common reasons for mechanical integrity citations in Process Safety Management (PSM) audits. Click here for Part I and Part II. In this installment, we cover an additional five issues to look out for. Avoiding mechanical integrity citations in PSM audits is possible, just look out for these issues:
Mistake #8 - Failure to segregate rupture discs and safety valves in the warehouse
If rupture discs or relief valves of the same physical size but different pressure settings are in adjacent warehouse bins, they can easily be confused. To avoid confusion, segregate similarly sized parts to different areas of the warehouse. Clear labeling also helps prevent confusion.
Mistake #9 - Failure to segregate alloy materials in the warehouse
When alloy parts of different composition are in proximity, or when carbon-steel parts are in proximity to similar alloy parts, confusion is possible. One refinery’s coker outlet failed because a carbon steel outlet pipe was inadvertently substituted for a high-temperature alloy pipe. The resulting fire caused an extended production outage.
Segregate alloy parts from each other and from similar carbon steel parts. Having parts in different areas of the warehouse along with a clear labeling system can avoid confusion.
Mistake #10 - Failure to have a usable warehouse inventory system
Often, the warehouse inventory system is a “legacy” system that has been around for decades, and whose software is understood by only the few who have to use the system on a daily basis. If the complexity of the inventory system is excessive, personnel tend to make their own “warehouse maps” that reside in personal lockers.
The problem with such a “warehouse map” system is that when the warehouse personnel opt to move materials, the maintenance and operations personnel who must use the warehouse (often after normal business hours) don’t get the word. This can lead to mistakes being made in selection of plant spares with sometimes-catastrophic consequences.
The warehouse inventory system must be user-friendly, understood by all personnel who are expected to use it, and available at all hours. Documentation must exist (written at the level of those who must understand the documentation) and be available as well.
Mistake #11 - Failure to train personnel on the warehouse inventory system
Even if a usable warehouse inventory system exists, in many cases the instructions on how to use the system are passed on verbally. This means that over time, inaccuracies abound that may lead to improper parts selection.
All mechanics, operators, and shift foremen who are expected to use the inventory system should receive formal, standardized training on the use of the system. The training should be documented in writing, and the trained users should have to periodically demonstrate their competency in using the inventory system. Should changes occur in the software or the physical layout of the warehouse, all users should receive update training and demonstrate their understanding. Software and physical layout changes should be tracked via MOC.
Mistake #12 - Failure to implement additional safeguards when running with equipment deficiencies
When inspections identify equipment deficiencies, and immediate repair or replacement is not possible, consideration should be given to the prudence of additional safeguards. The safeguards should be sufficient to ensure safe operation between the time that a deficiency is identified and the time that the deficiency can be eliminated. Such safeguards may include reductions in flow, temperature, or pressure until the equipment is repaired. Any such considerations should be documented via MOC.
What is prudent?
