For Top Performance, Know Your Critical Equipment

Tammy Shipps | April 21, 2014

26 March 2014
Jane Alexander, Deputy Editor



Real-world benefits go well beyond easier decision-making.


It’s not possible or necessary for all equipment in a plant to receive equal attention. The key is to focus on the most critical assets—whatever that means to an operation. Applying the principles of asset criticality can facilitate your decision-making and generate a number of other valuable benefits in the process.

Your site’s critical-equipment determinations should be based on business goals and objectives, says manufacturing consultant and MT&AP Contributing Editor Bob Williamson. Identify your most critical assets and rank them on a scale based on risk (probability and consequences) or other impact they might have on business goals and values. In this process, you’ll also identify your least critical assets and those somewhere in the middle. “Focused improvement on the most critical few that you ultimately move into a ‘maintenance fast lane’ will lead to enhanced performance,” says Williamson, “and possibly free up reactive maintenance resources to perform more planned/preventive maintenance work.”

Modern asset-management methods call for proper attention to be paid to equipment systems throughout their life cycles: from design and procurement through installation, commissioning, operation and maintenance to renewal and/or decommissioning. This is not something a site can just add to its wish list and forget: The new International Asset Management Standard (ISO-55000, issued in January 2014) requires asset risks to be identified and appropriate risk-management practices put in place.

It’s important to remember that “critical equipment” not only includes production-related processes, utilities, facilities equipment and the automated systems that run them, but also health, safety and environmental-related equipment. Often, your most critical assets may also be the most at risk if they fail to perform reliably.

The following story by PotashCorp’s Matthew Fenwick makes a good case for how establishment of sound criticality determinations can set the stage for a variety of payoffs. In this first-person account, Fenwick discusses improvements in alert-monitoring-device strategies that, among other things, allow his team to save time and better manage an increasing workload.

Matthew Fenwick, instrumentation technician with PotashCorp in New Brunswick, tells the following story about how they dug deeply to improve efficiency.

Our nine-person instrumentation team at PotashCorp’s New Brunswick (NB) division had responsibility for managing 2000 input/output (I/O) points in 2012. Knowing a 4400 I/O point expansion would come online in 2013, we had to find ways to save time and manage the workload. We needed to prioritize the right devices and alerts, reduce time spent on troubleshooting and increase technician efficiency.



With improved maintenance, PotashCorp NB is prepared for growth.

Identifying the right devices
We first tackled the Alert Monitor function in our asset-management system, Emerson’s AMS Device Manager. With hundreds of alerts coming in, we needed to know which ones were most important for our business. We started by rating plant areas based on criteria such as safety considerations, regulatory compliance, product quality, process throughput and operational cost. Next, we prioritized the loops and devices according to how critical the asset is and how often it fails.

The resulting maintenance priority index gave us insight into which areas to target for process changes and which alerts should be configured and channeled to the maintenance-planning department. We’ve established a weekly checkpoint to monitor and process these alerts as part of a proactive maintenance approach. At a glance, technicians can view the Alert Monitor on any engineering station in our plant. They can identify the potential bad actors, do further investigation and make modifications to correct the deficiencies before they become failures.

Reducing troubleshooting
The next step was to dig deeper into the way we applied the principles of asset criticality to our daily work. Specifically, we needed to improve our valve signature management, which was historically our biggest and most expensive area of failure. My wake-up call was a 3:00 a.m. emergency for an issue with a major control valve, resulting in the loss of six hours of prime production. Our maintenance superintendent asked why we had not identified the problem earlier. I told him, “You can’t predict what you don’t scan.” In other words, if we’re not monitoring a device, we can’t predict when it will fail.

The experience led us to reexamine our asset criticality sheet and to recognize that we were not adequately accounting for the way our harsh environment was impacting valves. Potash mines are basically salt mines. Combined with the plant’s eastern seaboard location, there is potential for valves to be destroyed by humidity and salt from the outside and slurries from the inside.

Today, rather than relying on reactive maintenance strategies, we’re using predictive diagnostics to plan our work. To account for environmental impact, we adjusted our valve criticality to ensure we were looking at the valves that are most vulnerable. We calculated a Valve Maintenance Action Plan (VMAP), establishing rules to dictate how frequently we perform signatures. For example, if the VMAP is greater than 400, we perform signatures every three months. If the VMAP is 300-400, we perform them every six months.

We also make use of the VMAP information to set a schedule for Emerson’s AMS ValveLink performance diagnostic sweep. This gives us a snapshot of the integrity of the valve components using five online tests: Supply Pressure Diagnostic, Relay Adjustment Diagnostic, I/P & Relay Integrity Diagnostic, Travel Deviation Diagnostic and Air Mass Flow Diagnostic. We now have the information to know when we need a full off-line diagnostic test.

By using this methodology, we have a handle on our signatures and can decrease the negative effects that cause reduced tonnages and production losses. We have experienced less downtime due to valve failures. We are still in the preliminary stages of full valve maintenance reliability, but we anticipate significant benefits.



Potash flotation cells at the New Brunswick site.

Information at our fingertips
Besides focusing on prioritization, planning and proactive maintenance, we found ways to get more out of our technology. For example, when I joined the company in 2010, AMS Suite software was only used as a storage facility for configurations and device checks during start-ups. After I spent time exploring the tool in depth, I saw the potential to use it as a way to instantly bring information to technicians.

We created an embedded program in the AMS Device Manager—using a Microsoft Access Database run by Visual Basic—to provide access to all our maintenance documentation with the click of a mouse (no more searching in the maintenance shop or control room for the book with loop configuration diagrams). Similar to a personalized search engine, we have all needed documentation in an organized, easy-to-find format that we call the Instrumentation Information Web.

In 2012, we captured the impact of the Instrumentation Information Web through a pilot project. Our instrumentation planner estimated the team would spend 807 hours working on proactive maintenance tasks based on work orders. However, with the implementation of the Instrumentation Information Web, the department spent only 376 hours on proactive tasks, a savings of more than 50% over the course of the pilot.

We have also seen substantial savings in commissioning and alerts. We devised a manual for alarm configuration and installed it on a Wireless Mobile Worker application. This has saved thousands of hours in commissioning time.



Matthew Fenwick, Instrumentation Technician, PotashCorp NB

Realizing the potential
The secret to realizing the full potential of our technology lies in our corporation’s Champion Concept. Almost three years ago, Bob Emery, Instrument Supervisor, PotashCorp NB, developed the vision for specialization. He saw that with the number of technologies PotashCorp was implementing, there wouldn’t be enough time to train all technicians in all technologies. He also recognized the frustration he was seeing on his team, so he began developing champions for each technology.

Specialization brings other benefits for PotashCorp NB. The champion model increased our ability to respond more quickly and solve problems in-house. For example, the event logger was frequently overloaded because we had difficulty understanding how alerts propagated through integrated DeltaV, AMS Device Manager and ValveLink applications.

Our in-house technology champions and others performed testing and gained a thorough understanding of how alerts are processed. Working together, we created a guideline for configuring alerts in DeltaV. The approach allowed us to prevent nuisance alerts and filter by transmitter or card-level. This led to better alarm-management and reduced the burden on the event logger.

In addition to the benefits obtained by the company, we benefit professionally. Although initially the change was difficult, specialization allows us the time to hone our craft, develop deeper knowledge and engage our creativity.

We invested the time upfront to make significant changes in our maintenance practices. What we gained is confidence that we are monitoring the right assets, solving problems more quickly and giving our technicians what they need to do their jobs well. Our practice will continue to evolve, but now we’re ready for the plant growth that lies ahead.

Matthew Fenwick is an Instrumentation Technician for PotashCorp of Saskatchewan, in Penobsquis New Brunswick, Canada. A graduate of the Industrial Control Technology program, he has worked in mining and pulp and paper industries for the past 10 years. For more information on his success story, email

Some caveats

With the ISO-5500 Asset Management Standard, it’s more important than ever for operations to accurately define and document their critical equipment assets. A roadblock for facilities that haven’t yet completed this “must do”—or started on it—may be one of direction: What approach works best?

While you can find plenty of tools, checklists and helpful advice on making critical-equipment determinations, keep in mind that they don’t reflect universal solutions. What’s appropriate for one type of operation may not be for another. There are several factors for a site to consider before adopting a specific strategy, including its industry sector and any standards related to the assets used in it. Do your research.

An additional caveat comes from Doc Palmer, author of McGraw-Hill’s Maintenance Planning and Scheduling Handbook. While he applauds the use of criticality rankings in developing maintenance strategies, he cautions operations to not let those rankings complicate the reporting and addressing of the work itself. According to Palmer, personnel writing work requests need a simple way to communicate urgency based on time. “If we’re not careful,” he says, “injecting the criticality ranking into some calculated equation could hinder the ease of this important communication.” (Palmer’s article “Simplify Your Priority System,” from the May 2010 issue of this magazine, discusses various priority systems.)MT&AP

For more information on principles of asset criticality, refer to Bob Williamson’s Jan. 2013 Uptime column, “Equipment Criticality: Life in the Fast Lane,” or email

For more information on how the application of asset-criticality principles meshes with successful maintenance planning and scheduling, please visit, or email





Tammy Shipps

View Comments

Sign up for insights, trends, & developments in
  • Machinery Solutions
  • Maintenance & Reliability Solutions
  • Energy Efficiency
Return to top