Criticality Analysis Helps Prioritize Assets

1. Binary approach: divides a list of assets with a hard-cutoff line where everything above the line is critical and everything below is non-critical. The binary approach is self-defeating and improperly uses the criticality analysis to justify ignoring or under-maintaining many assets. Even assets below the cutoff line need some attention, and those assets—if neglected—can create problems that become critical. The so-called “non-critical” assets can have emergencies that force the maintenance team into a reactive maintenance mode.
2. Dynamic approach: force-ranks every asset into a list where each asset is more critical than the one below it; start at the top of the list and get through as many assets as possible in a given period. Force-ranking often requires false precision and apples-to-oranges comparisons of dissimilar assets. It places too much emphasis on the mechanics of the scoring criteria and makes the scoring system work too hard. As people work on their way down the list, they can only maintain assets based on their available resources. While this approach offers the feel of flexibility, it ultimately ignores many assets and is unpredictable.
3. Every asset on its own: a highly subjective variation of the dynamic approach; scheduling important assets for maintenance more frequently and less-important assets less frequently. This is the most common approach because to many, it feels like the best of all worlds. People can work their way down to the bottom of the criticality list (eventually) without increasing any resources. But good maintenance scheduling is a cornerstone of any top-performing maintenance program. People commonly fall into the trap of confusing scheduled maintenance with sufficient maintenance. They think simply having maintenance on a schedule is effective maintenance, and over time, they respond to time constraints by simply “thinning out” the schedule to push things out further—or they simply let tasks go overdue.
4. Full coverage: concludes that most of the equipment is critical; scales up resources to have full coverage on all critical assets. They double the maintenance staff, send everyone to full cross-training and certification, and buy all new tools. Or worse, they may choose to keep their existing staff working perpetual overtime. This is the most expensive approach. In some cases, you are trading high immediate costs for long-term savings. Because of the high cost, this approach draws a lot of attention and scrutiny from upper management, heightening pressure to deliver immediate ROI. If any machines go down, it is often seen as proof that the maintenance program isn’t solving the problem. This breeds managerial impatience for immediate short-term returns. Finally, this approach implies that better maintenance is outside of our power. It suggests that improvement is determined entirely by circumstances and resources.

These four approaches are inflexible, unsustainable, and miss the root cause because they breed the wrong maintenance culture. A better approach is to divide your asset list into different classes, depending on how you plan to maintain each asset. There is more than one kind of critical.

A better way to classify your assets

A better way to manage this criticality dilemma is to get away from a simplistic “critical” or “non-critical” framework and re-classify your assets into more groups with very important distinctions. Take the preceding criticality scoring criteria and use it to answer one simple question:

Non-critical assets can be divided into two groups: “semi-critical” and “non-critical”

Semi-critical

Downtime/failure = strain on production or compliance. This is highly dependent on lead time. If strain on production leads to loss of production, assets that can be easily repaired or replaced within that timeframe are classified as semi-critical (assets that might not be repaired or replaced during that timeframe are critical).

Downtime = strain on production or compliance

“Semi-critical assets” are those that, when they go down, don’t necessarily stop production—but they do put strain on the system. Think of a warehouse or distribution center that has four forklifts. If one goes down, things keep moving, but the remaining forklifts must work 33% faster or longer. Or think of a rivet press that goes down, resulting in production personnel having to manually drive the rivets to keep up the production volume.

In some cases, a company or a process can only tolerate the loss of a semi-critical asset temporarily before it becomes unsustainable or the process falls too far out of balance.

Non-critical

There may be reasons to fix these assets, but not because of direct production loss or compliance—those are not affected by non-critical assets.

Downtime = no immediate effect on production

“Non-critical assets” do not affect the company’s ability to generate revenue—no matter how big, expensive, or complex they may be. For example, consider a rotating company sign in from of a building.

What about municipal services, public facilities, non-profit organizations, or other entities that don’t generate revenue? For those cases, replace the idea of generating revenue with fulfilling the organization’s mission, operating within budget, or providing the expected level of service.

It’s important to remember that criticality classification is unique to each company. What may be a non-critical luxury at one company may well be a star athlete at another. There are multiple tools that can help you keep your plant up and running. 

Additional Resources:

When and how to use and set up vibration monitoring on assets

4 ways maintenance teams benefit from remote power monitoring 

View the original article here.