Mechanical Integrity and Prior Operating Experience
Within the Mechanical Integrity (MI) paragraph of the PSM regulation (Title 8 §5189(j)), facility owners are required to “establish and implement written procedures to maintain the ongoing integrity of process equipment”. Inevitably, compliance with the requirements of this paragraph will require a schedule to be developed which describes the frequency that inspection, testing, and maintenance of process equipment is performed.
When determining the frequency of an MI task, the regulation requires the facility owner to consider three factors:
- Manufacturer’s recommendations;
- Good engineering practice; and
- Prior operating experience.
While all three factors are important, “prior operating experience” is often neglected as a basis for determining task frequency. Let’s consider an example.
I recently inspected a facility that utilized an Evapco condenser. Evapco’s Maintenance Checklist (manufacturer’s recommendation) indicates that the condenser pan should be cleaned and flushed quarterly, or as needed.
IIAR Bulletin No. 110 §6.4.2.3 (good engineering practice) recommends that the facility “Clean and flush pan, and check operating level in pan and adjust float valve monthly, if required”.
The facility considered both sources and opted to follow the manufacturer’s recommendation for cleaning the condenser pan quarterly. My inspection of the facility happened to coincide with quarterly cleaning and I was concerned by what I observed:
When I questioned the facility personnel regarding the amount dirt in the pan, they insisted that they were following the manufacturer’s recommendation for pan cleaning. Unfortunately, they had ignored the third factor in determining MI task frequency, prior operating experience.
When performing MI tasks, if degradation has occurred which could result in equipment failure, it is required that the frequency of related MI tasks be increased to help reduce the likelihood of a mechanical integrity failure. It is important to consider when prior operating experience should supersede manufacturer’s recommendations and industry standards.
Excellent Analysis…