How Your Level Is Decided

You place each asset class on the ladder yourself. That placement is recorded but never scored. Your reported level is derived from six questions about what actually happens to a measurement, taken from the ISO 13374 functional blocks. The difference between the two is reported back to you as the claim gap.

Ostensive and Performative Capability

Optimal’s own framework.¹ It is the reason this assessment records your own placement as well as deriving a level.

Capability has two sides. The ostensive side is what an organisation documents, designs and governs: the strategy, the procedure and the documented plan. The performative side is what it measurably does: the reading actually taken, the diagnosis actually recorded, the work order actually raised.

Mature organisations frequently score well on the first and less well on the second. They are designing well and not yet fully executing. The distance between the two sides is the performativity gap, and it is a finding in its own right rather than an error to be corrected: a wide gap points at execution, a narrow one at design.

GARPI™ reports that gap across an organisation, by classifying its dimensions as ostensive or performative. This assessment does the same thing at a much finer grain. Your placement on the ladder is the ostensive statement, made before any evidence is gathered. The level derived from the six blocks is the performative reading. The difference between them is your claim gap, which is the performativity gap made measurable for one class of asset rather than for a whole organisation.

¹ Moyo (2018).

The Predictive Maintenance Ladder

Level names and definitions in italics are the published Predictive Maintenance 4.0 wording, quoted as issued. Level 0 is added by Optimal to record estates where no routine measurement takes place. The guidance beneath each is Optimal’s.

Level 0 – None

No routine measurement of condition. Repair on failure, or replacement on a calendar, with nothing measured in between.

Level 1 – Visual inspections

Periodic physical inspections; conclusions based solely on the inspector’s expertise. If an instrument read-out informs the conclusion, you are already above this level.

Level 2 – Instrument inspections

Periodic inspections; conclusions based on the inspector’s expertise and instrument read-outs. Most estates that have invested in measurement sit here, whatever the strategy document says.

Level 3 – Real-time condition monitoring

Continuous real-time monitoring, alerts based on pre-established rules or critical levels. The step up from level 2 is not a better instrument. It is that nobody has to be looking.

Level 4 – Predictive Maintenance 4.0

Continuous real-time monitoring, alerts based on predictive techniques such as regression analysis. The distinction from level 3 is a method that produces a number with a confidence, rather than an experienced view.

The Six Functional Blocks

Block names are those defined by ISO 13374. The plain-English readings are Optimal’s.

B1 – Data Acquisition

The act of measuring. Whether condition is measured at all, and whether that measurement is human, periodic or continuous. Everything above depends on it.

B2 – Data Manipulation

What happens to a reading after it is taken. Whether it is tagged to the asset, kept and reachable later without a specialist request.

B3 – State Detection

The comparison that decides something has changed: a reading held against a baseline or a limit. Whether a person or a system makes that comparison is the single distinction between level 2 and level 3.

B4 – Health Assessment

The diagnosis. What is degrading, how far and against which failure mode.

B5 – Prognostic Assessment

The estimate of how long remains before functional failure, and with what confidence.

B6 – Advisory Generation

Whether the finding becomes a work order with the right parts and urgency. Recorded beside the level rather than inside it.

One Asset, All Six Blocks

An illustration, not a case study. Take a boiler feed pump.

1. B1 Vibration and bearing temperature are taken monthly on a route with a handheld analyser. Portable instruments, periodic.
2. B2 The readings are stored against the pump’s equipment number and the planner can pull them up. Aligned, retained and reachable.
3. B3 An analyst compares the spectrum with the machine’s own baseline and flags a rising component. Specialist judgement.
4. B4 The record names drive-end bearing wear and how far it has gone. Held by failure mode.
5. B5 The trend is projected to estimate how long remains before the alarm limit is reached, with a confidence. Predicted by regression.
6. B6 A work order is raised for the bearing change at the next outage, with the bearing reserved. Routed to a work order.

That estate is at level 2 for this class, because the measurement is periodic. Fitting permanent instrumentation would move B1 to continuous, and only then does level 3 become available. Being strong at B5 does not lift the level while B1 remains periodic – which is the kind of finding this instrument exists to surface.

Terms

Derived level

The level calculated from your six block answers. It is what your result reports.

Claim gap

The difference between where you placed the class and the level derived from the blocks. It is the performativity gap expressed for a single asset class: what is claimed against what is evidenced.

Functional failure

The point at which the asset stops doing what is asked of it, which is usually earlier than breakdown.

Failure mode

The specific way an asset fails, named rather than described as a general fault.

Answering level

The ISA-95 level your answers describe, from enterprise down to a single work unit. It is what makes two responses comparable.

Not known

A permitted answer on any block question. It removes that block from the derivation rather than scoring it as zero, so it is always better than guessing.