Most operations carry a recurring, recoverable reliability cost that never appears as a single line on the P&L. This instrument provides an indicative estimate of that exposure — conservatively modelled, with the methodology shown in full. It is a starting point for a conversation, not a substitute for analysis.
This estimate is deliberately conservative. It models the recoverable portion of reliability cost — the share an operation can realistically address through reliability governance — not the full theoretical cost of unreliability. Every assumption is stated below so the figure can be examined, challenged, and validated against your own data.
| Parameter | Defensible range | Applied |
|---|---|---|
| Unplanned share of unavailability | 0.50 – 0.70 | 0.65 |
| Recovery factor (production loss) | 0.15 – 0.35 | low → high |
| Reactive maintenance premium | 0.08 – 0.15 | low → high |
| Capital / inventory inefficiency | 0.02 – 0.05 | low → high |
The low end of the range applies the most conservative recovery factors; the high end applies the upper bounds. The range itself is the honesty of the estimate.
On total Cost of Unreliability (CORU): the full CORU of an operation is materially larger than the figure shown here. This instrument deliberately reports only the recoverable exposure — the addressable portion — to avoid overstatement. The complete CORU is established during a Fleet Stability Audit.
Methodology aligned with reliability data discipline, asset management governance, and RCM principles — including ISO 14224, ISO 55000, and SAE JA1011. These standards inform the modelling approach; they do not prescribe this specific formula. Figures are indicative and intended for executive discussion, not financial reporting.
An indicative figure tells you the exposure exists. A Fleet Stability Audit tells you exactly where it sits, what it costs, and how to recover it.
The 15-day diagnostic converts this estimate into a quantified, board-ready Executive Risk Report — validated against your CMMS and breakdown data.
Explore the Fleet Stability Audit →